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Roger E. Moore
2018-Nov-15, 02:56 AM
Since high school I've been reading about strange events that occurred on Earth and in space that were never completely resolved. I wasn't much into UFO or hysterical stuff. Real mysteries with some hard evidence were best.

Here was my short list of 25 weirdest things. NOTE: Some have been resolved in the last 2 years, more on those soon. NOTE: I had a few other mysteries, but some of those were solved a few years ago (like the WOW! signal).

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1. 1490 A.D.: What happened during the so-called Ch'ing-yang event, which Chinese historical records say was a fall of rocks from the sky that killed 10,000 people? Was it a giant meteor airburst or impact?

2. 774-775 A.D.: What caused the superabundance of carbon-14 detected in ice cores and tree rings worldwide? Did the Sun erupt?

3. August 7, 1921: What was the bright object briefly seen near the Sun by multiple reputable observers worldwide, now called the Mysterious Lick Object of 1921? If it was a comet, why was it not seen before or after this time?

4. 1650+: What causes the transient lunar phenomena around the crater Aristarchus (lights, reddish glows, radiation) detected by many observers over the centuries since 1650 (Hevelius), lately including robot spacecraft and Apollo 11 astronaut Michael Collins?

5. March 5, 2011: What causes the long-term, irregular variability in the light we receive from KIC 8462852, a.k.a. Tabby's Star?

6. July 2007: Did a comet or meteor airburst over North America produce the Younger Dryas cold period, 12,900 years ago, killing off the woolly mammoths and damaging the human Clovis culture of that time?

7. February 9, 1913: What was the true nature of the "Freight Train" meteor procession seen over the Western Hemisphere this night? How were these objects able to maintain such a tight aerial formation?

8. May 12, 2017: What produces the weird radio signals recently detected from the nearby red dwarf Ross 128?

9. August 12-13, 1883: Did Mexican astronomer José A. y Bonilla observe a giant comet pass by us, so close that it nearly hit us? If so, why was the comet otherwise unreported?

10. Sept 3, 2002: What is object J002E3, discovered orbiting Earth but now in solar orbit? Is it an Apollo-Saturn artifact or something else?

11. April 2016: Is there a little asteroid, tentatively named S509356, going around Earth in a 30000 x 152000 km x 48 degree orbit? If so, why have we not detected it before now?

12. Sept 1, 1859: With the 1859 Carrington event in mind (and Mystery #2), could our sun one day soon release a flare so large it could destroy our civilization?

13. July 29, 1953: Is there a gigantic "natural bridge" on the Moon in Mare Crisium, as reported by multiple observers worldwide, or is it just an illusion? If it is an illusion, what creates the effect?

14. November 1998: Why did no astronomer or historian document a historically recent supernova, the remnants of which we now call "Vela Jr.", that appears to have exploded during the Middle Ages about 1200-1300 A.D.? Is Vela Jr., much older than initially thought? Is it possible the supernova was seen by civilized humans and documented somewhere?

15. April 9, 1984: What created the giant mushroom cloud sighted by three airliners in 1984 over the Sea of Japan? Was it an airburst from a large meteor?

16. 1979-1980: How was the kinky, spiral-braided F Ring of Saturn created, and what forces or bodies maintain its twisted shape?

17. May 2008: What kind of object is the bizarre "planet" Fomalhaut b, a.k.a. Dagon? What is its true orbit, or is it merely "passing through" the system?

18. February 18, 1930: Is there a ninth planet in solar orbit beyond Neptune, out in the Kuiper Belt or Scattered Disk, whose existence was implied by orbital irregularities found in 2016? Do other planets exist in the Oort Cloud? Why were previous searches for "Planet X" (after Pluto's 1930 discovery) unsuccessful?

19. c.4 B.C.: What was the Star of Bethlehem, reported in the Bible in the gospel of St. Matthew? Did it even exist?

20. June 30, 1908: What caused the 1908 Tunguska aerial explosion over Siberia? Why was so little material from the airburst recovered despite severe damage to the ground environment?

21. October 28, 1937: Why do we keep failing to detect significant asteroid flybys until the objects are right upon us or have passed Earth by, from asteroid (69230) Hermes until this day?

22. 1821: What is the peculiar body orbiting Almaaz (epsilon Aurigae) that eclipses the yellow supergiant every 27 years? Also, how large is Almaaz and how far away is it, and why it is so difficult to discover these things even using the best technology we have?

23. 1975: Does the Black Hole Information Loss Paradox, as laid out by Stephen Hawking, actually violate the laws of physics as we know them?

24. 1961: Do Kordylewski dust clouds exist at the Earth-Moon L4 and L5 Lagrange points? Are these a transient phenomenon, vanishing and reappearing over time, explaining why some observers see them and others do not? Can the clouds be photographed, as Kordylewski claimed he did in 1961?

25. Why does the sun-grazing asteroid (3200) Phaethon sometimes act like a comet? Is it in fact not an asteroid but a dead comet nucleus? Also, what is (3200) Phaethon's astronomical history, given its odd activity and association with many other small bodies?

26. August 15, 1977: What was the "WOW!" signal picked up by Ohio State radio astronomers at the 21 cm line?

KaiYeves
2018-Nov-15, 05:20 AM
I was going to suggest Transient Lunar Phenomena in general, not just at Aristarchus, but I think that entry can stand in for that question.

Roger E. Moore
2018-Nov-15, 12:18 PM
I was going to suggest Transient Lunar Phenomena in general, not just at Aristarchus, but I think that entry can stand in for that question.

There seem to be quite a few of them, with the red glow around Aristarchus being the most common. Found some catalogs of TLP reports, will post links.


Below are a few of the mysteries that were very recently cleared up (at least mostly so).

.

Roger E. Moore
2018-Nov-15, 12:25 PM
Mystery #24: The Kordylewski Clouds -- THEY EXIST. Dr. Kordylewski's reputation is solid.

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Here is the original discovery paper, but it is in German.

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1961AcA....11..165K&data_type=PDF_H IGH&whole_paper=YES&type=PRINTER&filetype=.pdf

Photographische Untersuchungen des Librationspunktes L5 im System Erde-Mond

Kordylewski, K.
Acta Astronomica, Vol. 11, p.165
Publication Date: 00/1961

===============

Seeing the clouds was extremely difficult. The idea of having dust clouds at the Lagrange points was so reasonable and logical it was impossible to completely refute the idea even if you never saw them. It is my impression that there was a pan-nationalistic element involved in discussion of the clouds, with Eastern European and Russian astronomers being much more accepting of the idea, and more willing to publish about them, than Western European and American astronomers. No one, however, seems to have come out vehemently against the clouds existence. Everyone kept puzzling at the mystery of whether something so close to us could go unseen for so long. Perhaps space weather from the Sun swept the clouds away, only for them to re-form later.

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1962StAst..16...99H&data_type=PDF_H IGH&whole_paper=YES&type=PRINTER&filetype=.pdf

Report on Dr. K. Kordylewski's "Cloud Satellites": A Negative Observation of the L4 Position

Hodgson, R. G.
The Strolling Astronomer, Volume 16, Issue 5-6, p.99-100
Publication Date: 06/1962

Dr. Kordylewsi of Crakow Observatory in Poland claims discovery of two faint clouds near the L 5 point, 60° behind the Moon in its orbit. These he reports were visible to the naked eye on very dark, clear nights, and were first photographed early in 1961. He suspects that there may be also a cloud or clouds of satellites at theL 4 position, 60° ahead of the Moon in its orbit. A search for the objects was carefully extended at least 15° and up to 20° in every direction from the L 4 position. The whole area was swept completely several times. There was no evidence of any clouds or whitish patches. From this observation I conclude that if there is a cloud or clouds of satellites at or near the L 4 position, it or they must be quite faint, and well below the threshold of naked eye visibility.

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A check of the SAO/NASA search engine for research papers reveals quite a few papers over the years covering the mechanics of how such dust clouds could form and evolve. I will skip these (they are easy to find, just using the astronomer's name and the word "clouds" in the search engine). Here are the two "re-discovery" papers, showing what has to be done in order to actually see the dust clouds clearly -- polarized filters must be used.


https://academic.oup.com/mnras/article/480/4/5550/5089220

Celestial mechanics and polarization optics of the Kordylewski dust cloud in the Earth-Moon Lagrange point L5 - I. Three-dimensional celestial mechanical modelling of dust cloud formation

Slíz-Balogh, Judit; Barta, András; Horváth, Gábor
Monthly Notices of the Royal Astronomical Society, Volume 480, Issue 4, p.5550-5559 (11/2018)

Since the discovery in 1772 of the triangular Lagrange points L4 and L5 in the gravitational field of two bodies moving under the sole influence of mutual gravitational forces, astronomers have found a large number of minor celestial bodies around these points of the Sun-Jupiter, Sun-Earth, Sun-Mars and Sun-Neptune systems. The L4 and L5 points of the Earth and Moon might be empty due to the gravitational perturbation of the Sun. However, in 1961, the Polish astronomer, Kazimierz the Polish astronomer, Kazimierz Kordylewski found two bright patches near the L5 point, which might refer to an accumulation of interplanetary particles. Since then, this formation has been called the Kordylewski dust cloud (KDC). Until now, only a very few computer simulations have studied the formation and characteristics of the KDC. To fill this gap, we have investigated a three-dimensional four-body problem consisting of the Sun, Earth, Moon and one test particle, 1 860 000 times separately. We mapped the size and shape of the conglomerate of particles that have not escaped from the system sooner than an integration time of 3650 d around L5. Polarimetric observations of a possible KDC around L5 will be presented in a following second part to this paper.

==============

https://academic.oup.com/mnras/article/482/1/762/5114270

Lagrange point L5 – Part II. Imaging polarimetric observation: new evidence for the existence of Kordylewski dust cloud

Slíz-Balogh, Judit; Barta, András; Horváth, Gábor
Monthly Notices of the Royal Astronomical Society, Volume 482, Issue 1, Pages 762–770 (1 January 2019)

Telescopes mounted with polarizers can study the neutral points of the Earth’s atmosphere, the solar corona, the surface of planets/moons of the Solar system, distant stars, galaxies, and nebulae. These examples demonstrate well that polarimetry is a useful technique to gather astronomical information from spatially extended phenomena. There are two enigmatic celestial objects that can also effectively be studied with imaging polarimetry, namely the Kordylewski dust clouds (KDCs) positioned around the L4 and L5 triangular Lagrangian libration points of the Earth–Moon system. Although in 1961 the Polish astronomer Kazimierz Kordylewski had observed two bright patches near the L5 point with photography, many astronomers assume that these dust clouds do not exist, because the gravitational perturbation of the Sun, solar wind, and other planets may disrupt the stabilizing effect of the L4 and L5 Lagrange points of the Earth and Moon. Using ground-born imaging polarimetry, we present here new observational evidence for the existence of the KDC around the L5 point of the Earth–Moon system. Excluding artefacts induced by the telescope, cirrus clouds, or condensation trails of airplanes, the only explanation remains the polarized scattering of sunlight on the particles collected around the L5 point. By our polarimetric detection of the KDC we think it is appropriate to reconsider the pioneering photometric observation of Kordylewski. Our polarimetric evidence is supported by the results of simulation of dust cloud formation in the L5 point of the Earth–Moon system presented in the first part (Slíz-Balogh et al. 2018) of this paper.

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Press release with news of rediscovery of Kordylewski clouds

https://ras.ac.uk/news-and-press/research-highlights/earths-dust-cloud-satellites-confirmed

Roger E. Moore
2018-Nov-15, 01:47 PM
Mystery #3: The Lick Object (or Bright Object) of 1921 -- Probably a comet, as carefully researched in a paper from 2015. Amazing detective work.

I was introduced to this story through William Corliss's excellent, Mysterious Universe, a Fortrean-style collection of weird astronomical reports dating back centuries, with strong emphasis on the 19th and 20th centuries (newspaper accounts, etc.).

The tale of the Mysterious Lick Object of 1921 is often repeated in UFO literature as "proof" that UFOs exist, aliens are among us, etc. Regardless of that, the story is a classic. At a dinner party on the evening of August 21st, 1921, given by the director of Lick Observatory in California, W.W. Campbell (https://en.wikipedia.org/wiki/William_Wallace_Campbell) and his wife, a bright object was seen near the sun. In attendance were the following guests who also saw the bright object:

* Captain Eddie V. Rickenbacker, WWI flying ace and Medal of Honor recipient, later head of Eastern Airlines (https://en.wikipedia.org/wiki/Eddie_Rickenbacker);
* Major Reed Chambers, WWI flying ace, and Mrs. Chambers (https://en.wikipedia.org/wiki/Reed_McKinley_Chambers); and
* Professor Henry Norris, director of Princeton Observatory, New Jersey (https://en.wikipedia.org/wiki/Henry_Norris_Russell), co-creator of the Hertzsprung–Russell diagram.

Wikipedia links are provided to show how well known all the viewers were in their time, and thus how huge an impact the 1921 Bright Object made on the science world, despite the very short viewing time they had. Their reputations were unquestionable. If they said they saw something, they saw it.

================

W.W. Campbell wrote the first record of the object's existence, as seen from the U.S.A. The story, told from the third person, is electric in effect as it is an eyewitness account.

http://articles.adsabs.harvard.edu/full/1921PASP...33..258C?fbclid=IwAR1JsXzSnEWZMxdAcX-2KDxxTq18fz2GAX2iE65wnGnELceQiYBCFlI_89Y
(click through the story, page by page, and read story that comes after)

Observations of an Unidentified Object Seen near the Sun on Sunday, August 7, 1921

Campbell, W. W.
Publications of the Astronomical Society of the Pacific, Vol. 33, No. 195, p.258 (PASP Homepage)
Publication Date: 10/1921

=================

More news.

http://articles.adsabs.harvard.edu/full/1921JRASC..15..364P
(click through the story, page by page)

The Unidentified Bright Object Seen Near the Sun, August 7, 1921

Pearce, J. A.
Journal of the Royal Astronomical Society of Canada, Vol. 15, p.364
Publication Date: 12/1921

===========

The object was also briefly seen in Germany, per this article in French, also from 1921.

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1921GazA....8R..39.&data_type=PDF_H IGH&whole_paper=YES&type=PRINTER&filetype=.pdf

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The probable solution: it was a long-period comet, visible for only a tiny fraction of time.

https://arxiv.org/abs/1510.06445

Pairs and Groups of Genetically Related Long-Period Comets and Probable Identity of the Mysterious Lick Object of 1921

Zdenek Sekanina, Rainer Kracht (Submitted on 21 Oct 2015 (v1), last revised 26 Oct 2015 (this version, v2))

We present the history of investigation of the dynamical properties of pairs and groups of genetically related long-period comets (other than the Kreutz sungrazing system). Members of a comet pair or group move in nearly identical orbits and their origin as fragments of a common parent comet is unquestionable. The only variable is the time of perihelion passage, which differs from member to member considerably due primarily to an orbital-momentum increment acquired during breakup. Meter-per-second separation velocities account for gaps of years or tens of years, thanks to the orbital periods of many millennia. The physical properties of individual members may not at all be alike, as illustrated by the trio of C/1988 A1, C/1996 Q1, and C/2015 F3. We exploit orbital similarity to examine whether the celebrated and as yet unidentified object, discovered from the Lick Observatory near the Sun at sunset on 1921 August 7, happened to be a member of such a pair and to track down the long-period comet to which it could be genetically related. Our search shows that the Lick object, which could not be a Kreutz sungrazer, was most probably a companion to comet C/1847 C1 (Hind), whose perihelion distance was ~9 R-sun and true orbital period approximately 8300 years. The gap of 74.4 years between their perihelion times is consistent with a separation velocity of ~1 m/s that set the fragments apart following the parent's breakup in a general proximity of perihelion during the previous return to the Sun in the 7th millennium BCE.

Roger E. Moore
2018-Nov-15, 01:54 PM
Mystery #13: The Moon Bridge -- This is now known to be an optical illusion seen by astronomers viewing the Moon, one of about a half-dozen such illusions. Weird, but mystery solved.

Rather than go through the whole history of O'Neill's Bridge and other lunar illusions, a link is provided below to a thread started by Centaur that covered the topic well enough.

https://forum.cosmoquest.org/showthread.php?169578-Lunar-X-2018-AUG-18&p=2457687#post2457687

Roger E. Moore
2018-Nov-15, 02:01 PM
Mystery #6: The Younger Dryas Asteroid Impact -- Probably happened, but the mechanics need to be worked out now that the astrobleme has been found in Greenland. Probably solved.

Again, rather than go through the whole mystery from start to present, another thread has already been started about it with the discovery of the giant Greenland crater.

https://forum.cosmoquest.org/showthread.php?170423-Mega-crater-discovered-in-Greenland-12-000-years-old&p=2466986#post2466986

Roger E. Moore
2018-Nov-15, 02:05 PM
Mystery #5: Tabby's Star -- cause is still unresolved.

Again (again), another thread hereabouts does this phenomenon justice better than I could here. Updates are being posted, everyone is waiting for The Answer.

https://forum.cosmoquest.org/showthread.php?158813-Up-to-22-Dips-Detected-in-Starlight-1-500-LY-Away&p=2319289#post2319289

Roger E. Moore
2018-Nov-15, 02:11 PM
Mystery #10: J002E3 -- Probably the S-IVB from Apollo 12. Covered several times in this forum. Wikipedia link has a lot of data and more links.

https://forum.cosmoquest.org/showthread.php?163533-does-Junk-rot-in-space&p=2384721#post2384721
Does Junk Rot in Space?

https://forum.cosmoquest.org/showthread.php?161710-Could-asteroid-2016-HO3-be-another-Saturn-V-S-IVB-third-stage&p=2360657#post2360657
Could asteroid 2016 HO3 be another Saturn V S-IVB third stage?

https://en.wikipedia.org/wiki/J002E3
Wikipedia link

Roger E. Moore
2018-Nov-15, 03:25 PM
Mystery #26: The WOW! signal -- My bad, I had thought that the WOW! signal had been resolved. Apparently it has not.

The two links below describe the history of the WOW! signal much better than I can. It seems to remain unresolved, being the "perfect" alien detection signal, yet impossible to prove.

https://en.wikipedia.org/wiki/Wow!_signal

https://www.ohiohistory.org/learn/collections/history/history-blog/2010-(1)/july-2010/wow

===========

No luck replicating detection of the signal.

http://adsabs.harvard.edu/abs/1994Icar..112..485G

A search of the 'Wow' locale for intermittent radio signals

Gray, Robert H.
Icarus (ISSN 0019-1035), vol. 112, no. 2, p. 485-489 (12/1994)

In 1977 a search for extraterrestrial intelligence (SETI) at Ohio State University (OSU) recorded a strong signal near the 21-cm hydrogen line, which displayed several characteristics that might be expected of a candidate interstellar radio signal. This event was not repeatable with the OSC meridian transit radio telescope but could have been due to an intermittent source, which would be difficult to reobserve with a transit instrument. This article reports a search for the OSU signal using the fully steerable Harvard-Smithsonian 26-m radio telescope, tracking for up to 4 hr at a time to improve the chances of detecting an intermittent source. Despite higher sensitivity and longer cumulative observations, no signals resembling the OSU event were found.

===========

No luck replicating the detection of the signal (again).

http://adsabs.harvard.edu/abs/2002ApJ...578..967G

A Search for Periodic Emissions at the Wow Locale

Gray, Robert H.; Ellingsen, Simon
The Astrophysical Journal, Volume 578, Issue 2, pp. 967-971. (10/2002)

The Ohio State University Radio Observatory recorded a strong, narrowband emission near the 21 cm hydrogen line in 1977 during a search for extraterrestrial intelligence, an event known as the ``Wow'' signal. The few independent attempts to replicate the detection have failed. We have investigated the possibility of a periodic source-perhaps rotating and illuminating us once each cycle of many hours, like a lighthouse-which prior observations would have been unlikely to detect. We used the University of Tasmania Hobart 26 m radio telescope to search for intermittent and possibly periodic emissions at the Wow locale by tracking the apparent source positions for nearly 14 hr continuously on multiple days. No emissions resembling the Wow were detected over a bandwidth of 2.5 MHz to a flux density limit of about 18 Jy, with a detection threshold of 5.9 σ and rms noise of 3 Jy. We conclude that the Wow was not due to a source within our flux density limits and repeating more often than every 14 hr, although the possibility of a longer period or nonperiodic source cannot be ruled out.

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In the mid-2010s, the possibility was raised that the WOW! signal was the accidental detection of comets. Two references below describe this possibility. I had thought this take on the mystery solved it, but it seems I was wrong.

https://www.newscientist.com/article/dn28747-famous-wow-signal-might-have-been-from-comets-not-aliens/

Famous Wow! signal might have been from comets, not aliens

By Jesse Emspak, 11 January 2016

QUOTE: On 15 August 1977, radio astronomers using the Big Ear radio telescope at Ohio State University picked up a powerful signal from space. Some believe it was our first interception of an alien broadcast. Now it seems something closer to home may have been the source: a pair of passing comets.

The signal – known as the “Wow! signal” after a note scribbled by astronomer Jerry Ehman, who detected it – came through at 1420 megahertz, corresponding to a wavelength of 21 centimetres. Searchers for extraterrestrial transmissions have long considered it an auspicious place to look, as it is one of the main frequencies at which atoms of hydrogen, the most common element in the universe, absorb and emit energy. What’s more, this frequency easily penetrates the atmosphere.

But in the 40 years since, we’ve never heard anything like it again. Analysis of the signal ruled out a satellite, and a reflected signal from the Earth’s surface is unlikely because regulations forbid transmission in that frequency range.

==============

The research paper favoring a cometary origin is below.

https://arxiv.org/abs/1706.04642

Hydrogen Clouds from Comets 266P Christensen and P2008 Y2 (Gibbs) are Candidates for the Source of the 1977 WOW!Signal

Antonio Paris, Evan Davies (Submitted on 14 Jun 2017)

On 1977 August 15, the Ohio State University Radio Observatory detected a strong narrowband signal northwest of the globular star cluster M55 in the constellation Sagittarius. The frequency of the signal, which closely matched the hydrogen line (1420.40575177 MHz), peaked at approximately 2316 EDT. Since then, several investigations into the Wow signal have ruled out the source as terrestrial in origin or other objects such as satellites, planets and asteroids. From 1977 July 27 to 1977 August 15, comets 266P Christensen and P2008 Y2 (Gibbs) were transiting in the neighborhood of the Chi Sagittarii star group. Because the frequency for the Wow! signal fell close to the hydrogen line, and the hydrogen clouds of 266P/Christensen and P/2008 Y2 (Gibbs) were in the proximity of the right ascension and declination values of the Wow signal, the comet(s) and or their hydrogen clouds are strong candidates for the source of the 1977 Wow signal.

===============

Not everyone agrees, and the "con" side is detailed below.

http://naapo.org/WOWCometRebuttal.html

Dr. Robert S. Dixon
Director, Ohio State University SETI Program
published by NAAPO: North American Astrophysical Observatory, June 6, 2017

QUOTE: This is a statement regarding the claim that the “WOW!” signal was caused by hydrogen emission from an unknown comet or comets. It points out inaccuracies which are fatal to the theory that the “WOW!” signal was caused by a slow-moving comet. It also points out missing details from the author’s paper.

The staff of the OSU Radio Observatory has examined the paper by Paris regarding the “WOW!” signal (Paris, Antonio. HYDROGEN LINE OBSERVATIONS OF COMETARY SPECTRA AT 1420 MHZ) and comet 266/P Christensen.

We conclude that comet 266/P Christensen is not the source of the “WOW!” signal for a number of reasons. [article goes on to detail reasons]

Jean Tate
2018-Nov-15, 05:20 PM
Some comments on a few of these:

11. April 2016: Is there a little asteroid, tentatively named S509356, going around Earth in a 30000 x 152000 km x 48 degree orbit? If so, why have we not detected it before now?

Because it's faint and was not in parts of the sky covered by the usual asteroid hunters? Also applies to 21. October 28, 1937: Why do we keep failing to detect significant asteroid flybys until the objects are right upon us or have passed Earth by, from asteroid (69230) Hermes until this day?

12. Sept 1, 1859: With the 1859 Carrington event in mind (and Mystery #2), could our sun one day soon release a flare so large it could destroy our civilization?

Too soft? What does "destroy our civilization" mean? If something like "severely disrupt the global economy, indirectly cause millions of deaths" sort of thing, then the answer surely is "yes, very likely". But why is this a mystery? Isn't the future, in any form, a mystery?

16. 1979-1980: How was the kinky, spiral-braided F Ring of Saturn created, and what forces or bodies maintain its twisted shape?

I thought this one was solved? Isn't the answer shepherd moons?

23. 1975: Does the Black Hole Information Loss Paradox, as laid out by Stephen Hawking, actually violate the laws of physics as we know them?

Surely not an astronomical mystery? And why this particular one? I mean, aren't there dozens of similar "mysteries" in theoretical physics?

Roger E. Moore
2018-Nov-15, 05:34 PM
Some comments on a few of these:

Please suggest some new mysteries. Always open to better ones. :)

Jean Tate
2018-Nov-15, 05:45 PM
Please suggest some new mysteries. Always open to better ones. :)
Well, it depends on what you mean by "mysteries"! :p

I'm pretty hopeless as far as "Wow! signal" type mysteries, but perhaps better at "Tabby's star" type ones. But most would be "open questions" type things, such as "what is the nature of dark matter?" or "have any supernovae or GRBs caused significant extinctions here on Earth?" or "where do UHECRs come from?"

Roger E. Moore
2018-Nov-15, 05:57 PM
Those are good. My tendency is to pick events with specific dates when something was noticed, it was weird and had to do with astronomy, and we're still trying to figure out what that was.

The GRBs-causing-extinction-events idea is particularly nice because we know something happened, we cannot entirely figure of why it happened, and astronomy might provide an answer.

Roger E. Moore
2018-Nov-15, 06:20 PM
16. 1979-1980: How was the kinky, spiral-braided F Ring of Saturn created, and what forces or bodies maintain its twisted shape?

I thought this one was solved? Isn't the answer shepherd moons?

I agree, but what I read seems to leave room for debate on the details. One could describe the mystery of how such a thing is possible as "mostly solved" now, but it took years. Here is a synopsis for other readers.


Mystery #16: The Braided F-Ring of Saturn

As Pioneer 11 passed by Saturn in August-September 1979, it photographed the planet and its rings in extreme detail. Weeks later, researchers studying the processed images discovered a complete, previously unseen ring around Saturn, not far beyond the brilliant outer A Ring. The discovery became known as the F Ring.

The F Ring is faint, only a few hundred kilometers wide. It was not otherwise remarkable until Voyager I flew past in November 1980 and snapped more pics. To everyone's astonishment, Voyager's photographs appeared to show that the F Ring was braided, consisting of a thin filament wound around a thicker one in a long spiral. The researchers were said to have been struck dumb at the images. Spiral-woven rings around a planet were technically impossible.

The later Cassini spacecraft has done much to clarify the matter, but it also introduced an enormous amount of new data that brought confusion to the fore. The F Ring has two shepherd moons, Pandora and Prometheus, orbiting just outside and inside of it. Prometheus seems to be sculpting the ring and keeping it in place. Orbital simulations that ran the moonlets back in time suggested that Prometheus and Pandora slammed into each other long ago and created the ring from impact debris. The impact was not hard enough to throw the material out of orbit around Saturn, but the debris scattered throughout the orbital halo.

It seems that as Prometheus reaches the outermost point in its orbit around Saturn, it rips material away from the ring (taking it back from the original collision), leaving "kinks and knots" and diagonal slashes behind in the ring. It is also possible that tiny moonlets we cannot see orbit *inside* of the F Ring and are themselves perturbed by Prometheus, their motions and gravity creating the thin spiral ring braiding the main one. Chunks of material within the ring constantly crash together and disintegrate. Influences on the ring we haven't yet detected might exist. The ring has been described as perhaps the most dynamically active place in the Solar System.

At the present, no one knows exactly how the F ring works. Popular science articles often present the causes of the F Ring's bizarre appearance as an open-and-shut case, everything resolved, but that is NOT how the science papers talk about the matter. (See the cautiously worded August 2015 paper in particular, below.)

brief overview: https://en.wikipedia.org/wiki/Rings_of_Saturn#F_Ring

========================

http://science.sciencemag.org/content/310/5752/1300?fbclid=IwAR1lQEamcBIeHTi4THVf2KjIsi-vKXiZ2fMz5MH7qdFjkBF_6J47aQaOEYU

Cassini Discovers a Kinematic Spiral Ring Around Saturn

S. Charnoz, C.C. Porco, E. Déau, A. Brahic, J.N. Spitale, G. Bacques, K. Baillie
Science, 25 Nov 2005: Vol. 310, Issue 5752, pp. 1300-1304
DOI: 10.1126/science.1119387

Since the time of the Voyager flybys of Saturn in 1980–1981, Saturn's eccentric F ring has been known to be accompanied on either side by faint strands of material. New Cassini observations show that these strands, initially interpreted as concentric ring segments, are in fact connected and form a single one-arm trailing spiral winding at least three times around Saturn. The spiral rotates around Saturn with the orbital motion of its constituent particles. This structure is likely the result of differential orbital motion stretching an initial cloud of particles scattered from the dense core of the F ring. Different scenarios of formation, implying ringlet-satellite interactions, are explored. A recently discovered moon candidate, S/2004 S6, is on an orbit that crosses the F-ring core at the intersection of the spiral with the ring, which suggests a dynamical connection between S/2004 S6 and the spiral.

=================

https://www.nature.com/articles/nature06999?fbclid=IwAR0mkl1cX1RVY0c9iGmP0-KjO-SAJwkIgs9JP4ZH2ymT-j_izCJ0bw9LtUg

The determination of the structure of Saturn’s F ring by nearby moonlets

Carl D. Murray, Kevin Beurle, Nicholas J. Cooper, Michael W. Evans, Gareth A. Williams & Sébastien Charnoz
Nature | volume 453, pages 739–744 (05 June 2008)

Saturn’s narrow F ring exhibits several unusual features that vary on timescales of hours to years. These include transient clumps, a central core surrounded by a multistranded structure and a regular series of longitudinal channels associated with Prometheus, one of the ring’s two ‘shepherding’ satellites. Several smaller moonlets and clumps have been detected in the ring’s immediate vicinity, and a population of embedded objects has been inferred. Here we report direct evidence of moonlets embedded in the ring’s bright core, and show that most of the F ring’s morphology results from the continual gravitational and collisional effects of small satellites, often combined with the perturbing effect of Prometheus. The F-ring region is perhaps the only location in the Solar System where large-scale collisional processes are occurring on an almost daily basis.

===============

https://www.nature.com/articles/ngeo2508?fbclid=IwAR2d_jZQDF5Fqt33zkCnhOjizFf5-qw3uFSdEQA4IF1SFbsCM543Gy1nS5M

Saturn’s F ring and shepherd satellites a natural outcome of satellite system formation

Ryuki Hyodo & Keiji Ohtsuki
Nature Geoscience |volume 8, pages 686–689 (17 August 2015 )

Saturn’s F ring is a narrow ring of icy particles, located 3,400 km beyond the outer edge of the main ring system. Enigmatically, the F ring is accompanied on either side by two small satellites, Prometheus and Pandora, which are called shepherd satellites1,2,3. The inner regular satellites of giant planets are thought to form by the accretion of particles from an ancient massive ring and subsequent outward migration4,5,6,7. However, the origin of a system consisting of a narrow ring and shepherd satellites remains poorly understood. Here we present N-body numerical simulations to show that a collision of two of the small satellites that are thought to accumulate near the main ring’s outer edge can produce a system similar to the F ring and its shepherd satellites. We find that if the two rubble-pile satellites have denser cores, such an impact results in only partial disruption of the satellites and the formation of a narrow ring of particles between two remnant satellites. Our simulations suggest that the seemingly unusual F ring system is a natural outcome at the final stage of the formation process of the ring–satellite system of giant planets.

==================

My take on reading the above is that, while the general mechanics of the F ring's operation are believed known, much guesswork remains on clarifying the details.

Roger E. Moore
2018-Nov-15, 08:37 PM
Some comments on a few of these:

11. April 2016: Is there a little asteroid, tentatively named S509356, going around Earth in a 30000 x 152000 km x 48 degree orbit? If so, why have we not detected it before now?

Because it's faint and was not in parts of the sky covered by the usual asteroid hunters?

Did some research and found out, oops, this is no longer a mystery. The earliest reports on the object were intriguing.

=============

http://www.planet4589.org/pipermail/jsr/2016-April/000096.html?fbclid=IwAR3xTUIfbT0b4fqECyZ3ULPmramYf 95joPIfOhzNiCmfArgijkntc1-DsYU
[JSR] Jonathan's Space Report, No. 724
Jonathan McDowell jcm at planet4589.org
Fri Apr 8 20:18:46 EDT 2016

S509356
Asteroid surveys have spotted an unknown Earth satellite, provisionally designated S509356, in a 30000 x 152000 km x 48 deg orbit. Looking at my historical lists, it might be an object associated with the Vela launches, although it's surprising it's only being spotted now. The region beyond GEO is poorly tracked by satellite surveillance systems but in recent years coverage by asteroid searchers has been fairly good.

=============

Now.... it seems to have been the upper stage of a Chinese launch vehicle. Plus, there was confusion in the reporting of the object. Mystery resolved.

=============

http://www.satobs.org/seesat/Apr-2016/0082.html
S509356: weird object in cis-lunar orbit

=========

https://www.projectpluto.com/pluto/mpecs/15019c.htm
(identified as a Chinese booster stage, 2015-019C)
"Pseudo-MPEC" for 2015-019C = NORAD 41929 = S509356 = WJ2AD07
Created 2018 Sep 17 13:26:37 UT using Find_Orb

==============

https://space.stackexchange.com/questions/27295/why-did-they-think-that-s509356-was-in-orbit-around-the-earth-where-is-the-disc
Why did they think that S509356 was in orbit around the Earth? Where is the disconnect?

antoniseb
2018-Nov-15, 10:36 PM
I was surprised to not see:
18 June 1178, Gervase of Canterbury's observation of an event on the Moon (near, but definitely not the crater Giordano Bruno).

KaiYeves
2018-Nov-16, 12:44 AM
I was surprised to not see:
18 June 1178, Gervase of Canterbury's observation of an event on the Moon (near, but definitely not the crater Giordano Bruno).

This NASA article suggests it may have been a meteor in Earth’s atmosphere that happened to be perfectly aligned with the moon from the monks’ point of view: https://science.nasa.gov/science-news/science-at-nasa/2001/ast26apr_1

I wonder if it could have been a somewhat smaller impact near Crater Bruno that would not have caused such a massive meteor storm on Earth? Presumably that whole area has been looked at closely by the recent probes in light of the theory of Bruno’s recent origin.

(Off-topic: reading the article lead me to look up the 1966 Leonids, which were mentioned as the kind of meteor storm we would expect to follow an impact as large as the one that created Bruno, and I learned there were also impressive but lesser displays in 1998-2002. I remember watching a very impressive meteor shower during the school year when I was in Elementary School, with many more meteors than I have ever seen subsequently. I can’t remember the grade or season, but it stood out to me that I was in school at the time and our science teacher had suggested we ask our parents to wake us up to watch, unlike watching the Perseids during summer vacation. Since I was in Elementary School from 2000-2004, it may very well have been the Leonids!)

Roger E. Moore
2018-Nov-16, 02:38 AM
I grew up learning that the impact WAS the crater Bruno. This is a lot of new info for me, a good thing.

Roger E. Moore
2018-Nov-18, 02:50 PM
Mystery #4: Transient Lunar Phenomena -- Below are the major NASA resources on transient lunar phenomena to be gathered from entering "site:nasa.gov transient lunar" into Google. The last entry is a nice catalog listing of many ancient and modern reports.

=================

https://science.nasa.gov/science-news/science-at-nasa/2007/23jan_ltps

Lunar Transient Phenomena
(text and audio)

January 23, 2007: If you stare at the Moon long enough, you start seeing things. "82 things to be exact," says Bill Cooke, leader of NASA's Meteoroid Environment Group. That's how many "transient phenomena" the group has video-taped since they started monitoring the night side of the Moon in Nov. 2005. "In 107 hours of observing, we've tallied 20 lunar meteors + at least 60 Earth-orbiting satellites + one airplane + one terrestrial meteor = 82 in all."

This is the first systematic count of lunar night-side phenomena. "It gives astronomers an idea of what to expect when they undertake a lunar monitoring program from Earth."

===============

https://ntrs.nasa.gov/search.jsp?R=19770059463

Lunar transient phenomena /LTP/ - Manifestations, site distribution, correlations and possible causes

Cameron, W. S.
NASA Technical Reports Server, Jun 01, 1977

More than 1400 observations of lunar transient phenomena (LTP), encompassing brightenings, darkenings, and gaseous, reddish, and bluish events, are analyzed in an attempt to determine the possible causes of LTP. Hypotheses considered include effects of earth tides on the moon, low-angle illumination, thermal luminescence, UV heating, solar-particle acceleration by the magnetopause of earth's magnetotail, terrestrial magnetotail bow-shock-front turbulence, cathode luminescence due to magnetotail effects, and solar-flare particle bombardment. Analysis are performed in terms of histograms of the number of observations vs. phase of anomalistic period and of number vs. moon's age, percentage of numbers of observed phenomena and percentage of expected numbers as well as their ratios, and albedo behavior over a lunation period of chosen permanent points in ten specific features. The results indicate that different phenomena may have different causes, strong tidal effects are dubious, correlations with sunrise are most frequent, and the distribution of all LTP sites is distinct from that of deep- and shallow-focus moonquake epicenters.

=================

https://sservi.nasa.gov/articles/erupting-gas-may-cause-lunar-flashes/

Erupting gas may cause lunar flashes

Solar System Exploration Research Virtual Institute
Posted by: Soderman/NLSI Staff | Source: Lucas Laursen/Nature News | 2009

Reports of ephemeral flashes of light seen on the Moon, dismissed by some as imaginary, could be due to the explosive discharge of gas beneath its surface. The analysis, by astronomer Arlin Crotts of Columbia University in New York, may breathe new life into investigations of its geological activity and history. Crotts mapped about 2,000 observations of bright flashes called transient lunar phenomena (TLPs) reported by astronomers during at least the past 350 years. The flashes last too long to be meteorite impacts, and many researchers have dismissed the reports as observational errors.

But when Crotts compared the most commonly reported sites of observation with a map of known gas leaks from the Moon’s surface, he found a strong correlation. “It really boils down to just a small number of sites where [TLPs] are happening consistently,” he says. “That’s almost exactly the same list of sites where people have seen radon [gas].”

“The prevailing paradigm is that there’s very little volatile [gas] activity in the Moon at all,” Crotts says. NASA’s Apollo missions and the more recent Lunar Prospector mission observed wisps of radon and argon gas. Planetary scientists tend to attribute the gas to slow leaks from radioactive decay below the Moon’s surface. But Crotts suggests that the gas may build up in high enough concentrations to burst through the lunar surface, and that these explosions may be the origin of TLPs.

original article:
http://www.nature.com/news/2009/090513/full/news.2009.465.html
Erupting gas may cause lunar flashes: Eyewitness reports of flickering Moon lights stand up to scrutiny.
Lucas Laursen | 13 May 2009
(see links to astrophysics journals at end of article)

=====================

https://ntrs.nasa.gov/search.jsp?R=20060032853

Lunar transient phenomena: what do the Clementine images reveal?

Buratti, B., et al.
NASA Technical Reports Server, Jul 01, 2000

Lunar Transient Phenomena (LTP) have been reported for at least 450 years. The events range from bright flashes, to reddish or bluish glows, to obscurations.

======================

The following is a large but worthwhile download of a 1978 report cataloging TLPs/LTPs

https://ntrs.nasa.gov/search.jsp?R=19780022214

Lunar transient phenomena catalog
NTRS Full-Text: [PDF Size: 8.0 MB, 109 pages]

Cameron, W. S.
NASA Technical Reports Server, July 01, 1978

This catalog lists 1468 descriptions of observed lunar transient phenomena reported in the literature.

Roger E. Moore
2018-Nov-18, 03:49 PM
Additional resources for those wishing to research TLPs on their own.


http://www.astrosurf.com/luxorion/ltp-r277-index.htm
NASA Technical Report R-277: Chronological Catalog of Reported Lunar Events
(links to three catalogs of events)

SEE ALSO:
http://www.astrosurf.com/luxorion/Illustrations/ltp-catalog-extension-2006.pdf
Lunar Transient Phenomena Catalog Extension
Winifred Sawtell Cameron | July 2006

http://www.astrosurf.com/lunascan/miss.html
The Lunascan Project
MISSION STATEMENT, updated Feb 9, 2013

===========================

http://user.astro.columbia.edu/~arlin/TLP/
Transient Lunar Phenomena Studies: Introduction - The Basics of TLPs
Columbia University NYC

Has synopses of research papers, many links.

Ongoing Projects: Robotic Lunar Imaging Monitor
Collaborators: Arlin Crotts, Paul Hickson, Cameron Hummels & Thomas Pfrommer
Description: We have constructed a lunar monitor at Cerro Tololo Interamerican Observatory in Chile for the purpose of detecting and investigating TLPs as well as any other short-lived lunar events. The monitor consists of two cameras, one low-resolution and high frame-rate (10km/pixel, 5Hz) and the other high-resolution and low frame-rate (1.2km/pixel, 0.1Hz), each sensitive to different phenomena. This monitor is continuously taking images of the Moon, and by using an algorithm to search for differences between consecutive images, it is capable of detecting TLPs more sensitively than the human eye. The monitor has acheived full operation.

==========================

http://www.armaghplanet.com/blog/whatever-happened-to-transient-lunar-phenomena.html
Whatever happened to Transient Lunar Phenomena?
Astronotes: Armagh Observatory and Planetarium's Stellar Blog
Feb 27, 2014, Article by Kerry Scullion, Education Support Officer

QUOTES: You may initially think this is something that only an astrophysicist could describe but put in simpler terms, TLP’s are the short-lived changes in brightness in areas on the surface of the moon, appearing as quick bright flashes, with some lasting seconds and some lasting for hours! These changes can also be of changing colours such as flashes of red or violet and some have even been recorded as ‘darkening’s.’ These occurrences also have sometimes been describe as a haze rather than flash of light so it appears any occurrence of light on or near the Moon’s surface whose origin is not know is referred to as a TLP. These occurrences are usually spotted by lone observers and mostly in the past by amateur astronomers but there have been studies on it to try and discover what they could actually be. It seems that with the first telescopes came the more regular reports of TLP’s including sightings recorded by the famous astronomer William Herschel. In April 1787 he reported that he had spotted three red glowing spots on the dark side of the moon. Herschel was so determined that he seen these that he even had King George III come to try and see them through his telescope.

===========================

https://www.universetoday.com/101387/mysterious-moon-flashes-transient-lunar-phenomena-could-be-linked-to-solar-cycle/
Mysterious Moon Flashes: Could the Transient Lunar Phenomena be Linked to the Solar Cycle?
April 14, 2013 by David Dickinson

An interesting study appeared recently in the British Astronomical Association’s (BAA) March 2013 edition of their Lunar Section Circular. The study is one of the most comprehensive looks at possible connections between Transient Lunar Phenomena and the Solar Cycle.

Study appears here (courtesy of the Wayback Machine)
https://web.archive.org/web/20130422133254/http://www.baalunarsection.org.uk/2013-03-lsc.pdf

==========================

http://iopscience.iop.org/article/10.1088/0004-637X/697/1/1

TRANSIENT LUNAR PHENOMENA: REGULARITY AND REALITY
Arlin P. S. Crotts
Published 2009 April 30 • The Astrophysical Journal, Volume 697, Number 1

Roger E. Moore
2018-Nov-18, 03:58 PM
TLPs from 2018 research papers, courtesy of arXiv.


https://www.hou.usra.edu/meetings/lunarvolatiles2018/pdf/5039.pdf

Lifetime of a Transient Atmosphere Produced by Lunar Volcanism

Tucker, O. J.; Killen, R. M.; Saxena, P.; Johnson, R. E.; Prem, P.
Lunar Polar Volatiles, held 7-9 August, 2018 in Laurel, Maryland. LPI Contribution No. 2087, 2018, id.5039
Publication Date: 08/2018

============

Example of current lunar observations for TLPs

http://adsabs.harvard.edu/abs/2018JALPO..60d...5R

ALPO Observing Section Reports

Reynolds, M. D., et al.
The Journal of the Association of Lunar and Planetary Observers, Volume 60, Number 4, p.5-20
Publication Date: 09/2018

==========

https://arxiv.org/abs/1710.08915

NELIOTA: First temperature measurement of lunar impact flashes

A.Z. Bonanos, et al. (Submitted on 24 Oct 2017 (v1), last revised 22 Jan 2018 (this version, v2))

We report the first scientific results from the NELIOTA (NEO Lunar Impacts and Optical TrAnsients) project, which has recently begun lunar monitoring observations with the 1.2-m Kryoneri telescope. NELIOTA aims to detect faint impact flashes produced by near-Earth meteoroids and asteroids and thereby help constrain the size-frequency distribution of near-Earth objects in the decimeter to meter range. The NELIOTA setup, consisting of two fast-frame cameras observing simultaneously in the R and I−bands, enables - for the first time - direct analytical calculation of the flash temperatures. We present the first 10 flashes detected, for which we find temperatures in the range ~1,600-3,100 K, in agreement with theoretical values. Two of these flashes were detected on multiple frames in both filters and therefore yield the first measurements of the temperature drop for lunar flashes. In addition, we compute the impactor masses, which range between ~100 g and ~50 kg.

Roger E. Moore
2018-Nov-18, 03:59 PM
Does anyone else have similar astronomic mysteries to discuss? Always open to more. One of those lifelong hobbies, collecting and researching them.

Roger E. Moore
2018-Nov-18, 04:58 PM
Mystery #9: Did a Mexican astronomer in 1883 spot a comet that almost hit the Earth? Here is the paper on which this issue is based.


https://arxiv.org/abs/1110.2798

Interpretation of the observations made in 1883 in Zacatecas (Mexico): A fragmented Comet that nearly hits the Earth

Hector Javier Durand Manterola, Maria de la Paz Ramos Lara, Guadalupe Cordero (Submitted on 12 Oct 2011)

In 1883, on the 12th and 13th of August, Mexican astronomer Jose A. y Bonilla observed several objects passing in front of the solar disk. In 1886 in the L'Astronomie magazine, he reported his observations without providing a hypothesis explaining the registered phenomena. Our objective in this work is to interpret, with current knowledge, what he observed in Zacatecas. Our working hypothesis is that what Bonilla observed in 1883 was a highly fragmented comet, in an approach almost flush to the Earth's surface. The fragmentation of the comet's nucleus is a phenomenon known since the XIX century. Using the results reported by Bonilla, we can estimate the distance at which the objects approach to the Earth's surface, their size, their mass and total mass of the comet before fragmentation. According to our calculations, the distance at which the objects passed over the Earth's surface, was between 538 km and 8,062 km, the width of the objects was between 46 m and 795 m and its length between 68 m and 1,022 m, the object's mass was between 5.58e8 kg and 2.5e12 kg. Finally, the mass of the original comet, before fragmentation, was between 1.83e12 and 8.19e15 kg, i.e., between 2e-3 and 8.19 times the mass of Halley Comet.

Jean Tate
2018-Nov-19, 07:38 AM
Not sure if you’ve heard this one: potassium flares in (red dwarf?) stars. Were the observations merely someone using matches to light a cigarette, too near the room with the spectrograph? Or were there genuinely strange flares seen only (?) in K lines?

StupendousMan
2018-Nov-19, 05:57 PM
Not sure if you’ve heard this one: potassium flares in (red dwarf?) stars. Were the observations merely someone using matches to light a cigarette, too near the room with the spectrograph? Or were there genuinely strange flares seen only (?) in K lines?

I suggest you read this article:

http://adsabs.harvard.edu/abs/1967PASP...79..351W

Van Rijn
2018-Nov-20, 05:50 AM
Does anyone else have similar astronomic mysteries to discuss? Always open to more. One of those lifelong hobbies, collecting and researching them.

Venusian ashen light, perhaps? (I don't think that's been mentioned here?) I suspect it is more an observer issue, but something of a mystery.

Most of the things I'd think of are issues where more data is needed, like Enceladus heat sources (from what I've read, tidal heating is insufficient for the amount of liquid water they think is there). You've already discussed TLPs, which are the first things that I think of. I can think of a few former mysteries, like the Martian "trees" (https://www.space.com/7775-strange-mars-photo-includes-tantalizing-tree-illusion.html). That appears to be due to CO2 sublimation when the surface warms.

Roger E. Moore
2018-Nov-20, 07:51 PM
Venusian ashen light, perhaps? (I don't think that's been mentioned here?) I suspect it is more an observer issue, but something of a mystery.

Never heard of it. Okay, that's weird. Found this.

http://adsabs.harvard.edu/abs/2014JBAA..124..209S

The Ashen Light of Venus: the oldest unsolved solar system mystery

Sheehan, W.; Brasch, K.; Cruikshank, D.; Baum, R.
Journal of the British Astronomical Association, vol.124, no.4, p.209-215 (08/2014)

The Ashen Light, a feeble glowing or colouration of the night-side of Venus, has been discussed ever since Riccioli reported it in 1643. It has been frequently, if intermittently, seen, under various guises, ever since; and though illusion (e.g. a contrast effect) has been suspected, its reality as a physical phenomenon of the planet has often been supported by observers. Theories to explain it are numerous and some have been rather far-fetched. In recent years, the most plausible have been a glimpse in the visible range of thermal emission from the hot lower atmosphere of the planet, or a glow produced by ultraviolet-, electron-, or ion-excited oxygen molecules in the upper atmosphere of the night-side. Two of the authors, Sheehan and Brasch, made a systematic study during the favourable Eastern elongation of spring 2012, consisting of visual observations and CCD images through a number of different telescopes and filters. With a special green filter, they recorded a glow. Artificial planet observations and imaging similar to those employed by previous investigators were also carried out, and showed similar features. We conclude that in all probability none of the known physical phenomena of Venus can explain the Ashen Light. Our evidence strongly supports the illusion theory.

ALSO: http://adsabs.harvard.edu/abs/2014JBAA..124..299G (possible solution?)

Roger E. Moore
2019-Jan-03, 04:29 PM
Mystery #17: What is the mysterious "planet" Fomalhaut b (Dagon)?


It appears Fomalhaut b is not a neutron star, but what it really is remains unknown.

https://arxiv.org/abs/1812.11656

Searches for Continuous Gravitational Waves from Fifteen Supernova Remnants and Fomalhaut b with Advanced LIGO

The LIGO Scientific Collaboration & the Virgo Collaboration (Submitted on 31 Dec 2018)

We describe directed searches for continuous gravitational waves from sixteen well localized candidate neutron stars assuming none of the stars has a binary companion. The searches were directed toward fifteen supernova remnants and Fomalhaut~b, an extrasolar planet candidate which has been suggested to be a nearby old neutron star. Each search covered a broad band of frequencies and first and second time derivatives. After coherently integrating spans of data from the first Advanced LIGO observing run of 3.5-53.7 days per search, applying data-based vetoes and discounting known instrumental artifacts, we found no astrophysical signals. We set upper limits on intrinsic gravitational wave strain as strict as 1×10 −25, on fiducial neutron star ellipticity as strict as 2 × 10^−9, and on fiducial r-mode amplitude as strict as 3 × 10^−8.

George
2019-Jan-03, 10:26 PM
How did the Sun become a yellow star and why are the Christmas gifts we opened this year still using that discoloration? I think I have a handle on it but perhaps not. [Not a grand mystery, but a colorful one if you will.]

KaiYeves
2019-Jan-04, 03:09 PM
How did the Sun become a yellow star and why are the Christmas gifts we opened this year still using that discoloration? I think I have a handle on it but perhaps not. [Not a grand mystery, but a colorful one if you will.]

Will your gravestone say “It’s white, not yellow!”?

George
2019-Jan-04, 04:57 PM
Will your gravestone say “It’s white, not yellow!”?

I expect to die of something like Yellow Fever, so I might plagiarize with "I told you I was sick!". [Given the white vs. yellow minor disputes, it would be nice to offer three incontrovertible evidences about something, namely me, myself and I. ;)]

Roger E. Moore
2019-Mar-08, 01:32 PM
Mystery #2. The answer to what caused the global radiation event in 774-775 A.D. remains unknown, but research continues.

https://arxiv.org/abs/1903.03075

The Celestial Sign in the Anglo-Saxon Chronicle in the 770s: Insights on Contemporary Solar Activity

Hisashi Hayakawa, et al. (Submitted on 7 Mar 2019)

The anomalous concentration of radiocarbon in 774/775 attracted intense discussion on its origin, including the possible extreme solar event(s) exceeding any events in observational history. Anticipating such extreme solar events, auroral records were also surveyed in historical documents and those including the red celestial sign after sunset in the Anglo-Saxon Chronicle (ASC) were subjected to consideration. Usoskin et al. (2013: U13) interpreted this record as an aurora and suggested enhanced solar activity around 774/775. Conversely, Neuhauser and Neuhauser (2015a, 2015b: N15a and N15b) interpreted "after sunset" as during sunset or twilight; they considered this sign as a halo display and suggested a solar minimum around 774. However, so far these records have not been discussed in comparison with eyewitness auroral records during the known extreme space-weather events, although they were discussed in relationship with potential extreme events in 774/775. Therefore, we reconstruct the observational details based on the original records in the ASC and philological references, compare them with eyewitness auroral observations during known extreme space-weather events, and consider contemporary solar activity. We clarify the observation was indeed "after sunset", reject the solar halo hypothesis, define the observational time span between 25 Mar. 775 and 25 Dec. 777, and note the parallel halo drawing in 806 in the ASC shown in N15b was not based on the original observation in England. We show examples of eyewitness auroral observations during twilight in known space-weather events, and this celestial sign does not contradict the observational evidence. Accordingly, we consider this event happened after the onset of the event in 774/775, but shows relatively enhanced solar activity, with other historical auroral records in the mid-770s, as also confirmed by the Be data from ice cores.

Roger E. Moore
2019-Mar-19, 01:33 PM
More on Mystery #2, that global radiation event of A.D. 774-775.

https://arxiv.org/abs/1903.06806

Do the Chinese Astronomical Records Dated AD 776 January 12/13 Describe an Auroral Display or a Lunar Halo? A Critical Re-examination

F. Richard Stephenson, et al. (Submitted on 15 Mar 2019)

The enhancement of carbon-14 in tree rings around AD 774/775 has generated wide interest in solar activity at that time. The historical auroral records have been examined critically. Of particular interest was the "white vapour" observed in China on AD 776 January 12/13. Both Usoskin et al. (2013, Astron. Astrophys. 55, L3; U13) and Stephenson (2015, Adv. Sp. Res. 55, 1537; S15) interpreted this record as an auroral display. Subsequently, Neuhäuser and Neuhäuser (2015, Astron. Nachr. 336, 225; NN15) proposed five "criteria" for the likeliness of aurorae and on this basis rejected an auroral interpretation. Instead, they interpreted it as a lunar halo, and suggested there were no auroral records as a proxy of solar activity in the interval AD 774-785. We consider if their "lunar halo hypothesis" and their auroral criteria could be of use in future researches on historical auroral candidates. We first show a counter-example for the lunar halo hypothesis from a parallel record on 1882 November 17, which was seen as a whitish colour, in the southerly direction, and near the Moon. We then consider NN15's criteria on colour, direction, and sky brightness and investigate other counter-examples from early-modern auroral observations. We also consider the extension of the white vapour in AD 776 according to the distribution of Chinese asterisms, and show that its large extension was inconsistent with the lunar halo hypothesis. Conversely, the streaks of white vapour penetrating the eight Chinese asterisms can be reproduced if we consider auroral-ray structures at altitudes between 97 km and 170 km, along geomagnetic field lines between the L-shells L=1.55 and 1.64. Our investigations show that we should consider candidate auroral records in historical documents not on the basis of the newly suggested a priori criteria by NN15 but on all the available observational evidence.

Roger E. Moore
2019-Mar-19, 07:48 PM
"The Ashen Light of Venus: the oldest unsolved solar system mystery"


ALPO observers try to find the Ashen Light in 2018, details on how to observer Venus and maybe see it on page 49.

http://cdsads.u-strasbg.fr/abs/2018JALPO..60c..41B
ALPO Observations of Venus During the 2014 Western (Morning) Apparition

Roger E. Moore
2019-Mar-24, 01:37 PM
Mystery #21. October 28, 1937: Why do we keep failing to detect significant asteroid flybys until the objects are right upon us or have passed Earth by, from asteroid (69230) Hermes until this day?

https://phys.org/news/2019-03-dangerous-asteroids-earth-hard.html

Why dangerous asteroids heading to Earth are so hard to detect
March 22, 2019 by Jonti Horner, The Conversation

Jean Tate
2019-Mar-24, 04:28 PM
I’m not sure if this counts, not least because my (admittedly modest) search for relevant papers came up blank.

Several decades ago, emulsions were dangled beneath high altitude balloons, to register cosmic ray tracks. IIRC, the width of such tracks strongly correlated with Z, so the composition of cosmic rays could be estimated.

Some such tracks seemed to be produced by super-heavy nuclei, way beyond Pb or even U. Evidence for the existence of long-lived super-heavy elements, produced in certain SNe? Or not a mystery at all?

antoniseb
2019-Mar-25, 02:14 PM
I’m not sure if this counts, not least because my (admittedly modest) search for relevant papers came up blank.

Several decades ago, emulsions were dangled beneath high altitude balloons, to register cosmic ray tracks. IIRC, the width of such tracks strongly correlated with Z, so the composition of cosmic rays could be estimated.

Some such tracks seemed to be produced by super-heavy nuclei, way beyond Pb or even U. Evidence for the existence of long-lived super-heavy elements, produced in certain SNe? Or not a mystery at all?
I remember seeing a presentation about this in the mid 1970s by someone refuting Price's claim to have seen a magnetic monopole. I don't think it was emulsions, but rather plexiglass sheets, that they then washed in acid to make little holes more obvious. I think both the monopole, and the superheavies were also (and more likely) explained by a nuclear interaction or decay of Uranium or Thorium happening on the way through the sheets.

Roger E. Moore
2019-Apr-17, 01:08 PM
Mysteries involving the appearance of large amounts of radiocarbons in the fossil record might be explained by this.

https://arxiv.org/abs/1904.07323

Causation of Late Quaternary Rapid-increase Radiocarbon Anomalies

G. Robert Brakenridge (Submitted on 15 Apr 2019)

Brief (less than 100 years) rapid-increase anomalies in the Earth's atmospheric radiocarbon production have previously been attributed to either gamma photon radiation from supernovae or to cosmic ray particle radiation from exceptionally large solar flares. Analysis of distances and ages of nearby supernovae remnants, the probable gamma emissions, the predicted Earth incident radiation, and the terrestrial radiocarbon record indicates that supernova causation may be the case. Supernovae include Type Ia white dwarf explosions, Type Ib, c, and II core collapse events, and some types of gamma burst objects. All generate significant pulses of atmospheric radiocarbon depending on distances. Surveys of supernova remnants offer a nearly complete accounting for the past 50,000 years. There are 18 events less than or at 1.4 kilo-parsec distance, and brief radiocarbon anomalies with appropriate sizes occurred for each of the closest events. In calendar years before 1950, these are: Vela, 22 per mil del 14C at 12,760; S165, 20 per mil at 7431; Vela Junior, 13 per mil at 2765; HB9, 9 per mil at 5372; Boomerang, 11 per mil at 10,255; and Cygnus Loop (per mil change not calculated) at 14,722. Although uncertainties remain large, the agreements of prediction to observation support a possible causal connection.

Grey
2019-Apr-17, 02:34 PM
Mysteries involving the appearance of large amounts of radiocarbons in the fossil record might be explained by this.That's awesome.

Roger E. Moore
2019-Apr-23, 12:43 PM
Mystery #21. October 28, 1937: Why do we keep failing to detect significant asteroid flybys until the objects are right upon us or have passed Earth by, from asteroid (69230) Hermes until this day?

https://phys.org/news/2019-03-dangerous-asteroids-earth-hard.html

Why dangerous asteroids heading to Earth are so hard to detect
March 22, 2019 by Jonti Horner, The Conversation

Here is another one. Finding NEAs is still a big problem for technical reasons, but they're working on it.

https://arxiv.org/abs/1904.09645

Towards Efficient Detection of Small Near-Earth Asteroids Using the Zwicky Transient Facility (ZTF)

Quanzhi Ye, et al. (Submitted on 21 Apr 2019)

We describe ZStreak, a semi-real-time pipeline specialized in detecting small, fast-moving near-Earth asteroids (NEAs) that is currently operating on the data from the newly-commissioned Zwicky Transient Facility (ZTF) survey. Based on a prototype originally developed by Waszczak et al. (2017) for the Palomar Transient Factory (PTF), the predecessor of ZTF, ZStreak features an improved machine-learning model that can cope with the 10× data rate increment between PTF and ZTF. Since its first discovery on 2018 February 5 (2018 CL), ZTF/ZStreak has discovered 45 confirmed new NEAs over a total of 232 observable nights until 2018 December 31. Most of the discoveries are small NEAs, with diameters less than ∼100 m. By analyzing the discovery circumstances, we find that objects having the first to last detection time interval under 2 hr are at risk of being lost. We will further improve real-time follow-up capabilities, and work on suppressing false positives using deep learning.

Jean Tate
2019-Apr-30, 08:16 PM
I remember seeing a presentation about this in the mid 1970s by someone refuting Price's claim to have seen a magnetic monopole. I don't think it was emulsions, but rather plexiglass sheets, that they then washed in acid to make little holes more obvious. I think both the monopole, and the superheavies were also (and more likely) explained by a nuclear interaction or decay of Uranium or Thorium happening on the way through the sheets.
Much delayed thanks! :)

Can anyone cite a paper on this?

Roger E. Moore
2019-Apr-30, 08:25 PM
Much delayed thanks! :)

Can anyone cite a paper on this?

Might be it. I think Alvarez wrote something on his own about it.
http://cdsads.u-strasbg.fr/abs/1975PhRvD..11.3099E

Jean Tate
2019-Apr-30, 08:43 PM
Might be it. I think Alvarez wrote something on his own about it.
http://cdsads.u-strasbg.fr/abs/1975PhRvD..11.3099E
Thanks.

There's this (http://cdsads.u-strasbg.fr/abs/2015PhR...582....1B) ("Non-collider searches for stable massive particles"), which I found by checking References and Cited Bys; it has 488 (!) References, among which may be one or more on highZ (highA?) cosmic rays.

Roger E. Moore
2019-May-01, 12:22 PM
If you like astronomical mysteries, the two ANITA events are pretty weird. Future ANITA issues will be posted in this thread, which seems to be where they belong.

===

https://arxiv.org/abs/1904.12865

Superheavy Dark Matter and ANITA's Anomalous Events

Dan Hooper, Shalma Wegsman, Cosmin Deaconu, Abigail Vieregg (Submitted on 29 Apr 2019)

The ANITA experiment, which is designed to detect ultra-high energy neutrinos, has reported the observation of two anomalous events, directed at angles of 27 ∘ and 35 ∘ with respect to the horizontal. At these angles, the Earth is expected to efficiently absorb ultra-high energy neutrinos, making the origin of these events unclear and motivating explanations involving physics beyond the Standard Model. In this study, we consider the possibility that ANITA's anomalous events are the result of Askaryan emission produced by exotic weakly interacting particles scattering elastically with nuclei in the Antarctic ice sheet. Such particles could be produced by superheavy (∼10 10 −10 13 GeV) dark matter particles decaying in the halo of the Milky Way. Such scenarios can be constrained by existing measurements of the high-latitude gamma-ray background and the ultra-high energy cosmic ray spectrum, along with searches for ultra-high energy neutrinos by IceCube and other neutrino telescopes.

===

https://arxiv.org/abs/1904.13396
Can the ANITA anomalous events be due to new physics?

James M. Cline, Christian Gross, Wei Xue (Submitted on 30 Apr 2019)

The ANITA collaboration has observed two ultra-high-energy upgoing air shower events that cannot originate from Standard Model neutrinos that have traversed the Earth. Several beyond-the-standard-model physics scenarios have been proposed as explanations for these events. In this paper we present some general arguments making it challenging for new physics to explain the events. One exceptional class of models that could work is pointed out, in which metastable dark matter decays to a highly boosted lighter dark matter particle, that can interact in the Earth to produce the observed events.

Solfe
2019-May-02, 12:50 AM
Does anyone else have similar astronomic mysteries to discuss? Always open to more. One of those lifelong hobbies, collecting and researching them.

Why are the numbers for the expansion of the universe due to dark energy so precise, but also so different depending on if you are working from CMB or supernovas. They aren't even in each other's error bars, which is odd.

Solfe
2019-May-02, 12:57 AM
As a historical footnote, the Nemesis star theory is interesting. It isn't much of mystery having been disprove to an extraordinary degree, but the discussion of it was pretty cool. It seemed to solve some problems but then had the obvious issue where it couldn't be found. It kind of highlights the difficultly in searching for Planet X, which is so much harder due to it's estimated size, distance, background stars, etc. Definitely nothing the size of the Nemesis star, but there could be a planet hiding out there. If they find Planet X what do you stop searching for other planets?

Roger E. Moore
2019-May-02, 12:57 PM
As a historical footnote, the Nemesis star theory is interesting. It isn't much of mystery having been disprove to an extraordinary degree, but the discussion of it was pretty cool. It seemed to solve some problems but then had the obvious issue where it couldn't be found. It kind of highlights the difficultly in searching for Planet X, which is so much harder due to it's estimated size, distance, background stars, etc. Definitely nothing the size of the Nemesis star, but there could be a planet hiding out there. If they find Planet X what do you stop searching for other planets?

My suspicion is that we will always be looking for the next planet or dwarf planet or weirdo body (e.g., Ultima Thule the Snowman) way out there, just because. And after Oumuamua, we should take a look now and then toward the solar apex to make sure nothing big like a rogue planet surprises us from that direction.

Jean Tate
2019-May-02, 04:36 PM
Thanks.

There's this (http://cdsads.u-strasbg.fr/abs/2015PhR...582....1B) ("Non-collider searches for stable massive particles"), which I found by checking References and Cited Bys; it has 488 (!) References, among which may be one or more on highZ (highA?) cosmic rays.
A VERY frustrating search!

Quite a few of those 488 look interesting, and some of the "Citations to the Article" very much so.

However, to see how relevant, I find that many require reading the actual published paper, as the Abstract is not enough. But guess what (no prizes for guessing correctly) ... they're behind paywalls! Even decades old papers!

"Search for superheavy elements in galactic cosmic rays", Bagulya+(2013) (http://cdsads.u-strasbg.fr/abs/2013JETPL..97..708B) may be an exception:


The charge distribution of approximately 6000 nuclei with charge numbers above 55 in galactic cosmic rays has been obtained in the OLIMPIYA project. Three superheavy nuclei with the charge numbers in the range 105 < Z < 130 have been detected. The regression analysis has provided a more accurate estimate of the charge number of one of these nuclei (119{-6/+10} with a probability of 95%). Such nuclei should form stability islands. Their detection in nature confirms theoretical predictions and justifies efforts for their synthesis under terrestrial conditions. The model calculations performed in this work possibly can explain the results of some experiments on the investigation of the charge composition of cosmic rays in which particles with charge numbers in the range 94 < Z < 100 were detected (they cannot enter into the composition of primary cosmic radiation because their lifetime is very short). The calculations indicate that events with Z > 92 are due to the fragmentation of heavier nuclei from the stability island, rather than to methodical inaccuracies or fault of instruments. Several such events have been revealed. Thus, the track method makes it possible to obtain the results very important for understanding of the physical picture of the world. The results obtained within the OLIMPIYA project show that the study of tracks of galactic cosmic rays in olivine crystals from meteorites opens new capabilities for the investigation of fluxes and spectra in cosmic rays in the region of heavy and superheavy nuclei.

Now if only there were a way to get the paper, without paying an extortionate sum of money ...

Roger E. Moore
2019-May-02, 04:46 PM
Much delayed thanks! :)

Can anyone cite a paper on this?

From Wikipedia: Alvarez, Luis W. "Analysis of a Reported Magnetic Monopole". In ed. Kirk, W. T. (ed.). Proceedings of the 1975 international symposium on lepton and photon interactions at high energies. International symposium on lepton and photon interactions at high energies, Aug 21, 1975. p. 967.

Hope this is the one.

https://digital.library.unt.edu/ark:/67531/metadc865371/

Free download PDF: https://digital.library.unt.edu/ark:/67531/metadc865371/m2/1/high_res_d/4174786.pdf

.

Jean Tate
2019-May-02, 08:00 PM
From Wikipedia: Alvarez, Luis W. "Analysis of a Reported Magnetic Monopole". In ed. Kirk, W. T. (ed.). Proceedings of the 1975 international symposium on lepton and photon interactions at high energies. International symposium on lepton and photon interactions at high energies, Aug 21, 1975. p. 967.

Hope this is the one.

https://digital.library.unt.edu/ark:/67531/metadc865371/

Free download PDF: https://digital.library.unt.edu/ark:/67531/metadc865371/m2/1/high_res_d/4174786.pdf

.
Very cool, thanks! :)

The level of detail, in making and presenting the “fragmentation” case is wonderful. True, this is not observational astronomy, so not, strictly speaking, comparable, but I feel many of “today’s” astronomy papers would benefit from almost pedantic detail like this.

Roger E. Moore
2019-May-09, 12:28 PM
More on the ANITA anomalies. Could Antarctica act as a sort of giant mirror?

https://arxiv.org/abs/1905.02846

Reflections On the Anomalous ANITA Events: The Antarctic Subsurface as a Possible Explanation

Ian M. Shoemaker, Alexander Kusenko, Peter Kuipers Munneke, Andrew Romero-Wolf, Dustin M. Schroeder, Martin J. Siegert (Submitted on 7 May 2019)

The ANITA balloon experiment was designed to detect radio signals initiated by neutrinos and cosmic ray air showers. These signals are typically discriminated by the polarization and phase inversions of the radio signal. The reflected signal from cosmic rays suffer phase inversion compared to a direct tau neutrino event. In this paper we study sub-surface reflection, which can occur without phase inversion, in the context of the two anomalous up-going events reported by ANITA. We find that subsurface layers and firn density inversions may plausibly account for the events, while ice fabric layers and wind ablation crusts could also play a role. This hypothesis can be tested with radar surveying of the Antarctic region in the vicinity of the anomalous ANITA events. Future experiments should not use phase inversion as a sole criterion to discriminate between downgoing and upgoing events, unless the subsurface reflection properties are well understood.

Noclevername
2019-May-19, 01:57 AM
25. Why does the sun-grazing asteroid (3200) Phaethon sometimes act like a comet? Is it in fact not an asteroid but a dead comet nucleus? Also, what is (3200) Phaethon's astronomical history, given its odd activity and association with many other small bodies?

It might have a dry surface with pockets of volatiles scattered underneath. When it heats up, sometimes the pockets burst and sometimes they stay intact.

Roger E. Moore
2019-May-23, 05:15 PM
Mystery #6: The Younger Dryas Asteroid Impact -- Probably happened, but the mechanics need to be worked out now that the astrobleme has been found in Greenland. Probably solved.

Again, rather than go through the whole mystery from start to present, another thread has already been started about it with the discovery of the giant Greenland crater.

https://forum.cosmoquest.org/showthread.php?170423-Mega-crater-discovered-in-Greenland-12-000-years-old&p=2466986#post2466986

A second Greenland astrobleme has been discovered. Look to this thread for information.

https://forum.cosmoquest.org/showthread.php?157267-The-Carolina-Bays-are-conic-sections&p=2484109#post2484109

A South American astrobleme has been found as well from the Younger Dryas period.

https://www.nature.com/articles/s41598-018-38089-y

Roger E. Moore
2019-Jun-07, 01:22 PM
Discovered an older thread about the "Younger Dryas Asteroid Impact" issue: https://forum.cosmoquest.org/showthread.php?69481-Evidence-for-a-comet-impact-12-900-years-ago-title-edited

Might be interesting for some.

Roger E. Moore
2019-Jun-18, 12:58 PM
Mystery #4: Transient Lunar Phenomena.

Transient Lunar Phenomena are still being explored. This man's theory is that moonquakes release interior gas, which reflects sunlight.

https://www.9news.com.au/technology/whats-causing-mysterious-flashes-of-light-on-the-moons-surface-news-science/02192f6b-6907-4dca-a038-fe6a3b524c73

Roger E. Moore
2019-Jun-28, 01:35 AM
More on the ANITA anomalies. No answers yet, just solutions that don't work out.

https://arxiv.org/abs/1906.11736

Anomalous ANITA air shower events and tau decays

Shoshana Chipman, Rebecca Diesing, Mary Hall Reno, Ina Sarcevic (Submitted on 27 Jun 2019)

Two unusual neutrino events in the Antarctic Impulse Transient Antenna (ANITA) appear to have been generated by air showers from a particle emerging from the Earth at angles 25-35 degrees above the horizon. We evaluate the effective aperture for ANITA with a simplified detection model to illustrate the features of the angular dependence of expected events for incident standard model tau neutrinos and for sterile neutrinos that mix with tau neutrinos. We apply our sterile neutrino aperture results to a dark matter scenario with long-lived supermassive dark matter that decay to sterile neutrino-like particles. We find that for up-going air showers from tau decays, from isotropic fluxes of standard model, sterile neutrinos or other particles that couple to the tau through suppressed weak interaction cross sections cannot be responsible for the unusual events.

Roger E. Moore
2019-Jun-29, 12:29 AM
21. October 28, 1937: Why do we keep failing to detect significant asteroid flybys until the objects are right upon us or have passed Earth by, from asteroid (69230) Hermes until this day?

Finally!

https://phys.org/news/2019-06-team-successfully-incoming-asteroid.html

June 27, 2019
Team successfully locates incoming asteroid
by Institute for Astronomy

For the first time, astronomers at the University of Hawaiʻi have demonstrated that their ATLAS and Pan-STARRS survey telescopes can provide sufficient warning to move people away from the impact site of an incoming asteroid. They detected a small asteroid prior to its entering the Earth's atmosphere near Puerto Rico on the morning of June 22, 2019.

Van Rijn
2019-Jun-29, 06:22 AM
Why do we keep failing to detect significant asteroid flybys until the objects are right upon us or have passed Earth by, from asteroid (69230) Hermes until this day?

One thing I recall reading is that part of the trouble is that it is hard to see asteroids that are between us and the sun, and much easier to see asteroids coming our way looking out away from the sun. As more and more asteroids are mapped, the issue decreases (since the asteroids we care about cross Earth orbit) but I believe it's also been suggested to put one or more space telescopes in closer solar orbit to look outward. (Perhaps in an Earth-Sun L1 halo orbit, for instance.)

antoniseb
2019-Jun-29, 08:29 PM
... I believe it's also been suggested to put one or more space telescopes in closer solar orbit to look outward. (Perhaps in an Earth-Sun L1 halo orbit, for instance.)
I think better still would be at the L4 & L5 points for Venus.

Roger E. Moore
2019-Jun-29, 08:54 PM
I think better still would be at the L4 & L5 points for Venus.

Venus Equilateral? Whatever works, do it.

Solfe
2019-Jul-02, 01:29 AM
Here is another: What happened to Wilhelm Albrecht Oeltzen? He is known for the processing of a part of Friedrich Wilhelm August Argelander's Zones from 1849-1852 in Bonn Germany. Often these are labeled "A. Oe." or "AOe" in catalogs. This was a two step process, I am uncertain if the abbreviations differentiate the two projects. In 1875, he disappeared. I have been unable to find any reference to what he was doing at that time.

Since the 1870s are an interesting time period, it would be no surprise that the man simply passed away of natural causes, far from home.

Edit: Hey! It took me a while to research this, why don't I post the key highlights of that work?

Born on Oct 2nd, 1824.
Studied at University of Göttingen in 1846.
First Assistant at Vienna Observatory 1849-1859, before moving to The Paris Observatory.
The Oeltzen's catalogue of Argelander's Southern Zones. 1857-58.
The Oeltzen's catalogue of Argelander's Northern Zones. 1851-52.
Schwerd's Beobachtungen von Circumpolarsternen in mittleren Positionen published in 1856, with Friedrich Magnus Schwerd.
"Disappeared" in 1875.

Roger E. Moore
2019-Jul-16, 01:08 AM
Back to the ANITA anomaly:

https://arxiv.org/abs/1907.06308

The pros and cons of beyond standard model interpretations of ANITA events
L. A. Anchordoqui, I. Antoniadis, V. Barger, F. Cornet, C. García Canal, M. Gutiérrez, J. I. Illana, J. G. Learned, D. Marfatia, M. Masip, S. Pakvasa, S. Palomares-Ruiz, J. F. Soriano, T. J. Weiler (Submitted on 15 Jul 2019)

The Antarctic Impulsive Transient Antenna (ANITA) experiment has observed two air shower events with energy ∼500 PeV emerging from the Earth with exit angles ∼30∘ above the horizon. As was immediately noted by the ANITA Collaboration, these events (in principle) could originate in the atmospheric decay of an upgoing τ-lepton produced through a charged current interaction of a ντ inside the Earth. However, the relatively steep arrival angles of these perplexing events create tension with the standard model (SM) neutrino-nucleon interaction cross section. Deepening the conundrum, the IceCube neutrino telescope and the Pierre Auger Observatory with substantially larger exposures to cosmic ντ's in this energy range have not observed any events. This lack of observation implies that the messenger particle (MP) giving rise to ANITA events must produce an air shower event rate at least a factor of 40 larger than that produced by a flux of τ-neutrinos to avoid conflicts with the upper limits reported by the IceCube and the Pierre Auger collaborations. In addition, the sensitivity of ANITA to MP-induced events must be comparable to or larger than those of IceCube and Auger to avoid conflict with the non-observation of any signal at these facilities. Beyond SM interpretations of ANITA events can be classified according to whether the MPs: (i) live inside the Earth, (ii) originate in neutrino-nucleon collisions inside the Earth, (iii) come from cosmological distances. In this communication we investigate the positive and negative facets of these three classes of models.

Roger E. Moore
2019-Jul-26, 05:14 PM
One thing I recall reading is that part of the trouble is that it is hard to see asteroids that are between us and the sun, and much easier to see asteroids coming our way looking out away from the sun. As more and more asteroids are mapped, the issue decreases (since the asteroids we care about cross Earth orbit) but I believe it's also been suggested to put one or more space telescopes in closer solar orbit to look outward. (Perhaps in an Earth-Sun L1 halo orbit, for instance.)

We missed another one yesterday, a city killer named 2019 OK.