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Thread: Will comet ison survive to perihelion?

  1. #31
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    Something else odd about this. It's not possible to know where a comet or body might calve. You can run simulations of possible situations/instances, where it is more likely calving/fragmentation will occur, but, it does not mean that the body will. Even then, I always thought that if a comet were to calve, that the pieces (those that survive), would generally continue in the same direction, unless interaction with another body such as a planet, causes a change. The general trajectory of this comet, around the sun, is pretty well be determined, I'm sure the effects of the sun, have also been well considered. The story also seems to have been banded about since as early as June 8 of this year. Checking the lisbon observatory website, now July 20, there is still no indication validating the assertion.

  2. #32
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    NASA’s Hubble makes Comet ISON movie

    http://www.skymania.com/wp/2013/07/n...vie.html/7751/

    (snip)The Hubble team have just released a movie made up from images taken by the orbiting telescope on 8 May as the comet was still travelling between the orbits of Jupiter and Mars and 650 million km (403 million miles) from Earth. - See more at: http://www.skymania.com/wp/2013/07/n....8FD6TQDm.dpuf

    the movie moves in reverse for some reason.

    SOHO will be able to view C/2012 S1 starting 27 November
    C/2012 S1 will come to perihelion (closest approach to the Sun) on 28 November
    http://en.wikipedia.org/wiki/C/2012_...and_visibility

  3. #33
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    the article was from July 2, 2013 6:45

    the movie is from May 8th.

    (snip)C3 images have a larger field of view: They encompass 32 diameters of the Sun. To put this in perspective, the diameter of the images is 45 million kilometers (about 30 million miles) at the distance of the Sun, or half of the diameter of the orbit of Mercury. Many bright stars can be seen behind the Sun.
    http://www.spaceweather.sflorg.com/c.../lasco_c3.html

    C/2012 S1 will enter SOHO 11-27 and reach perihelion the next day.

    so in other words it will travel 30 million miles in one day, but on May 8, it was 403 million miles from Earth.

    ????
    Last edited by rtsredux; 2013-Jul-21 at 08:32 AM. Reason: typo

  4. #34
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    Remember the Earth is moving. That is why the distances increased, decreased, increased and will decrease again.

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    Some astrophysicists including israeli David Eichler, correlates strong solar flares with sungrazer comets.
    http://www.forbes.com/sites/brucedor...ic-armageddon/

    I'm also tired about doomsday predictions, but who ever heard Major Ed Dames talk about Killshot events in his remote viewing researchs become a little worried about what could happend if only a similar 1859 carringhton event take place in our electronic dependent society.

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    A quick search on arxiv shows that only one unpublished paper by David Eichler proposed a link. Could not find any other papers suggesting there was one. Which other astrophysicists are you referring to? I'd say the odds of it are minuscule, there is no evidence and no mechanism that has been observed.

    I wouldn't worry about Ed Dames either: http://americanloons.blogspot.co.uk/...-ed-dames.html - the 1998 doomsday due to alien fungal spores didn't happen, the 1997 nuclear apocalypse wasn't triggered by North Korea, Mammoth mountain did not go boom, the 1998 economic collapse didn't happen (maybe the alien fungus reacted with it and they cancelled each other out), Europeans have not resorted to cannibalism, the sky was safe to look at for all of 1999 and the precursor doom flare of ultra-doom didn't show up and despite predicting his own powers would fade by 2011 he is still going.

  7. #37
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    Quote Originally Posted by Shaula View Post
    A quick search on arxiv shows that only one unpublished paper by David Eichler proposed a link. Could not find any other papers suggesting there was one. Which other astrophysicists are you referring to? I'd say the odds of it are minuscule, there is no evidence and no mechanism that has been observed.
    Correlation between sun-grazer comets and solar flares are not so unusual as you suspect.
    http://www.sciencedaily.com/releases...1206105005.htm
    This is a new field in astronomy and of course there are proponents and opponents of this idea.

  8. #38
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    Quote Originally Posted by Shaula View Post

    I wouldn't worry about Ed Dames either
    I'm not worried about Ed Dames predictions, but the effects of big solar flares and CMEs reaching our electronic dependent society

  9. #39
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    There is no correlation between CMEs and sun-grazing comets. A comet's mass is insignificant to the sun.

    For more reading: http://sungrazer.nrl.navy.mil/index....ws/comets_cmes

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    Quote Originally Posted by Mikeustinov View Post
    Correlation between sun-grazer comets and solar flares are not so unusual as you suspect.
    http://www.sciencedaily.com/releases...1206105005.htm
    This is a new field in astronomy and of course there are proponents and opponents of this idea.
    That article says nothing about the comet being linked to flares. It is using the comet as a probe of the coronal magnetic field structure, the understanding of which is important to understanding the origins of flares. Comets not required. I am not dismissing the idea utterly, I am saying that evidence has been looked for and not found. So the balance of probability is that there is no causal link. Even the original paper you mentioned is highly tenuous. It related heightened C-14 to a possible flare to a possible comet. Timing was very fuzzy.

    I'm not worried about Ed Dames predictions, but the effects of big solar flares and CMEs reaching our electronic dependent society
    Then I'd have picked just about anyone else to get information on what the consequences might be. I'd regard my dog as a more reliable person to tell me about solar flares. I'd expect the effects of such a CME as likely to be hugely expensive and damaging. But not a civilisation ending event. Some of the scare stories inflate the risk, from the ones I have read. And like NEOs while they may be very damaging these events are in essence just too darn expensive to completely protect against.

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    Quote Originally Posted by schlaugh View Post
    There is no correlation between CMEs and sun-grazing comets. A comet's mass is insignificant to the sun.

    For more reading: http://sungrazer.nrl.navy.mil/index....ws/comets_cmes
    http://www.nasa.gov/mission_pages/su...comet-cme.html

    On October 2, 2011, an exceptionally bright comet headed toward the sun and disintegrated. Moments later a large coronal mass ejection (CME) blew off the other side of the sun, making for this captivating movie from the SOlar Heliospheric Observatory (SOHO).

  12. #42
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    Quote Originally Posted by Shaula View Post
    I'd regard my dog as a more reliable person to tell me about solar flares. I'd expect the effects of such a CME as likely to be hugely expensive and damaging. But not a civilisation ending event. Some of the scare stories inflate the risk, from the ones I have read. And like NEOs while they may be very damaging these events are in essence just too darn expensive to completely protect against.
    Solar energy may soon eclipse nuclear power – only not in the way we hoped. According to NASA, the planet will soon face an outbreak of powerful solar flares capable of collapsing global power grids. Were this to happen, the world’s nuclear reactors could be left to run wild, overheat, melt, and explode.

    (snip)

    A Carrington-sized GMD could damage thousands of extra high voltage (EHV) transformers around the world. These transformers can weigh up to 300 tons and cost more than $1 million. Power grids cannot operate without them. Because each is custom-built to regional specifications, procuring new EHVs can take up to three years. Rebuilding a damaged grid could take decades. That could be the best-case scenario. More worrisome is imagining what would happen to nuclear power plants that are reliant on electrical grids.

    A 2011 Oak Ridge National Laboratory report warned of a 33 percent likelihood that a solar flare could lead to “long-term power loss” over a nuclear reactor’s life. With 440 nuclear power plants in 30 countries, and 250 research reactors, there are nearly 700 potential Fukushimas waiting to be unleashed.

    Faced with a grid collapse, nuclear plants must rely on backup power to cool reactor cores and spent-fuel ponds. But the Nuclear Regulatory Commission requires only eight hours of battery power and enough fuel to run emergency generators for a week. Restoring outside power to Fukushima’s damaged reactors was a daunting task even when Japan had a functioning grid to fall back on. If the Sun sends a geomagnetic tsunami sweeping across Earth, it could become impossible to provide any form of traditional power.

    more @http://www.earthisland.org/journal/index.php/eij/article/flare-up_how_the_sun_could_put_an_end_to_nuclear_power/

  13. #43
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    Quote Originally Posted by rtsredux View Post
    http://www.nasa.gov/mission_pages/su...comet-cme.html

    On October 2, 2011, an exceptionally bright comet headed toward the sun and disintegrated. Moments later a large coronal mass ejection (CME) blew off the other side of the sun, making for this captivating movie from the SOlar Heliospheric Observatory (SOHO).
    That's called a coincidence.

  14. #44
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    Quote Originally Posted by rtsredux View Post
    Solar energy may soon eclipse nuclear power – only not in the way we hoped. According to NASA, the planet will soon face an outbreak of powerful solar flares capable of collapsing global power grids. Were this to happen, the world’s nuclear reactors could be left to run wild, overheat, melt, and explode.

    (snip)

    A Carrington-sized GMD could damage thousands of extra high voltage (EHV) transformers around the world. These transformers can weigh up to 300 tons and cost more than $1 million. Power grids cannot operate without them. Because each is custom-built to regional specifications, procuring new EHVs can take up to three years. Rebuilding a damaged grid could take decades. That could be the best-case scenario. More worrisome is imagining what would happen to nuclear power plants that are reliant on electrical grids.

    A 2011 Oak Ridge National Laboratory report warned of a 33 percent likelihood that a solar flare could lead to “long-term power loss” over a nuclear reactor’s life. With 440 nuclear power plants in 30 countries, and 250 research reactors, there are nearly 700 potential Fukushimas waiting to be unleashed.

    Faced with a grid collapse, nuclear plants must rely on backup power to cool reactor cores and spent-fuel ponds. But the Nuclear Regulatory Commission requires only eight hours of battery power and enough fuel to run emergency generators for a week. Restoring outside power to Fukushima’s damaged reactors was a daunting task even when Japan had a functioning grid to fall back on. If the Sun sends a geomagnetic tsunami sweeping across Earth, it could become impossible to provide any form of traditional power.

    more @http://www.earthisland.org/journal/index.php/eij/article/flare-up_how_the_sun_could_put_an_end_to_nuclear_power/

    I agree with your concern regarding nuclear power and the possible consequences of a carrington style event. Fukishima was an example of how badly prepared we would be. However, what does this have to do with your post regarding comet ISON and fragments hitting earth?

  15. #45
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    Quote Originally Posted by schlaugh View Post
    That's called a coincidence.
    Seems to me that is too soon to confirm or dismiss any idea, since a lot of the observed comets occurs in solar minimum, time with virtually low chance of solar flares and CMEs. Comets have the power to trigger or increase some imminent solar flare? this answer no one can say for sure yet!
    Last edited by Mikeustinov; 2013-Jul-21 at 07:54 PM.

  16. #46
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    Quote Originally Posted by Concerned View Post
    I agree with your concern regarding nuclear power and the possible consequences of a carrington style event. Fukishima was an example of how badly prepared we would be. However, what does this have to do with your post regarding comet ISON and fragments hitting earth?
    it was re: what Shaula said.

    I'd expect the effects of such a CME as likely to be hugely expensive and damaging. But not a civilisation ending event. Some of the scare stories inflate the risk, from the ones I have read. And like NEOs while they may be very damaging these events are in essence just too darn expensive to completely protect against.

    If all nuke plants melted down it could very well be a "civilisation ending event. "

  17. #47
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    There was a thread around here about sungrazers and flares/CMEs, but google didn't find it. Here's a recent thread on Comet Ison causing a solar flare/CME.

    The threat from a Carrington event, while plausible, is overstated in some ways. The chances of the grids being up at the time of impact are minimal because sunwatchers will see the CME coming. So, we'd have to either lose that capability or allow it to lapse. However, it's possible for a second CME to arrive faster and be undetected because the first CME will have cleared the solar wind out of the way to allow for a faster propogation and satellites and other observatories may be offline for protection. Still, damage could result in either event, and even if the grid itself were saved, the shutdown itself could cause problems, such as with food spoilage and foundries seizing up (unless they are gas/or coal fired).

    Nuclear power plants might be problematic, as mentioned. And worse yet, a recent report showed that the backup generators have, in several cases, failed to turn on or work properly when needed. However, I suspect that nuclear plant linked grids will get priority transmission system repairs, even if they have to cannibalize other parts of the grid. However, I don't think Fukushima is an illustration of this problem, as the generators themselves were destroyed, and I don't think that would happen in a CME.
    Et tu BAUT? Quantum mutatus ab illo.

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    Can we please stop the CME discussions, that has nothing to do with the OP.
    Nor will we discuss other things here like Danes and Eichler and nuclear plants.
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  19. 2013-Jul-21, 08:49 PM
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  20. #49
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    essential links:

    home page of the SOHO/LASCO and STEREO/SECCHI comet program
    http://sungrazer.nrl.navy.mil/index.php

    NASA Comet ISON Observing Campaign
    http://www.isoncampaign.org/

    Hubble site ISON blog
    http://hubblesite.org/hubble_discoveries/comet_ison/

    Balloon Rapid Response for ISON
    http://brrison.jhuapl.edu/

    Anticipated STEREO observations of Comet ISON
    http://stereo-ssc.nascom.nasa.gov/comet_ison/

    Comet ISON orbital parameters and orbit viewer
    http://ssd.jpl.nasa.gov/sbdb.cgi?sst...012%20S1;orb=1

    NASA Comet ISON Toolkit
    http://solarsystem.nasa.gov/planets/...Display=Events
    Last edited by rtsredux; 2013-Jul-23 at 03:00 AM. Reason: added link

  21. #50
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    Quote Originally Posted by Concerned View Post
    Something else odd about this. It's not possible to know where a comet or body might calve. You can run simulations of possible situations/instances, where it is more likely calving/fragmentation will occur, but, it does not mean that the body will. Even then, I always thought that if a comet were to calve, that the pieces (those that survive), would generally continue in the same direction, unless interaction with another body such as a planet, causes a change. The general trajectory of this comet, around the sun, is pretty well be determined, I'm sure the effects of the sun, have also been well considered. The story also seems to have been banded about since as early as June 8 of this year. Checking the lisbon observatory website, now July 20, there is still no indication validating the assertion.
    here is a very interesting hour long discussion where scientists discuss the possibility of ISON breaking up after perihelion (towards the end of the video) along with artifacts in the Hubble images, and other things

    http://www.youtube.com/watch?v=xMagVxn3ILo#at=390

    personally, I think it might be able to be determined when it enters the fov of SOHO.

    Comet Lovejoy was bar shaped which was evident on C3 diff images. I predicted that it would survive perihelion based on that (which it did) The bar shaped reference is even mentioned on Wikipedia re: it's OUTBOUND flight.
    http://en.wikipedia.org/wiki/C/2011_...utbound_flight

    it was actually bar shaped PRIOR to perihelion as shown on the SOHO images which I demonstrated on another forum at the time

  22. #51
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    Quote Originally Posted by rtsredux View Post
    here is a very interesting hour long discussion where scientists discuss the possibility of ISON breaking up after perihelion (towards the end of the video) along with artifacts in the Hubble images, and other things

    http://www.youtube.com/watch?v=xMagVxn3ILo#at=390

    personally, I think it might be able to be determined when it enters the fov of SOHO.

    Comet Lovejoy was bar shaped which was evident on C3 diff images. I predicted that it would survive perihelion based on that (which it did) The bar shaped reference is even mentioned on Wikipedia re: it's OUTBOUND flight.
    http://en.wikipedia.org/wiki/C/2011_...utbound_flight

    it was actually bar shaped PRIOR to perihelion as shown on the SOHO images which I demonstrated on another forum at the time
    Its always possible the comet will break up, when considering how close proximity to the sun. Your original post asserted that this would lead to fragments possibly hitting earth. The latter is not likely.

  23. #52
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    Quote Originally Posted by tusenfem View Post

    Can we please stop the CME discussions, that has nothing to do with the OP.
    Nor will we discuss other things here like Danes and Eichler and nuclear plants.
    Let me just add to what tusenfem said.

    This is the second time we have warned about non-mainstream ideas in this thread. We are not going to issue a new warning for every possible non-mainstream idea related to this (or any) comet.

    If you have a question about a doomsday prediction about ISON, or wish to debunk a non-mainstream idea that is widely circulating around the Internet, that's fine. But don't even hint at advocating such an idea in this thread, you will be infracted. If you wish to advocate such an idea, create your own thread in ATM or CT.
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  24. #53
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    Quote Originally Posted by Concerned View Post
    Its always possible the comet will break up, when considering how close proximity to the sun. Your original post asserted that this would lead to fragments possibly hitting earth. The latter is not likely.
    the scientists discussed the possibility of it breaking up after perihelion starting at around 48 minutes.

    http://www.youtube.com/watch?v=xMagVxn3ILo#at=390

    they didn't get into what would happen if it did that, but they were joking around that it would "appeal to our sense of action movies and death and destruction." Not sure what he meant by that exactly, but it sounds sort of ominous. Another scientist said she wanted it to break up, so maybe some of the scenarios if that happened wouldn't be so bad.

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    Hi. I think a good link can be found here http://hubblesite.org/hubble_discoveries/comet_ison/. It's by Hubblesite. Will Comet ISON hit Earth = No. Rest easy.

  26. #55
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    Quote Originally Posted by Concerned View Post
    Hi. I think a good link can be found here http://hubblesite.org/hubble_discoveries/comet_ison/. It's by Hubblesite. Will Comet ISON hit Earth = No. Rest easy.
    one of the commenter's of that video brought up a good point imo.

    Why did the ancients all across the planet see comets as being a sign of doom?

    Here is an interesting article about that.

    Comets have inspired dread, fear, and awe in many different cultures and societies around the world and throughout time. They have been branded with such titles as "the Harbinger of Doom" and "the Menace of the Universe."

    They have been regarded both as omens of disaster and messengers of the gods. Why is it that comets are some of the most feared and venerated objects in the night sky? Why did so many cultures cringe at the sight of a comet?

    http://www.nasa.gov/mission_pages/de...ncient_prt.htm

  27. #56
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    Quote Originally Posted by Concerned View Post
    Hi. I think a good link can be found here http://hubblesite.org/hubble_discoveries/comet_ison/. It's by Hubblesite. Will Comet ISON hit Earth = No. Rest easy.
    Here's that video
    http://www.youtube.com/watch?v=skWt9...ature=youtu.be

    they didn't take into account that the comet might break up after reaching perihelion, which the scientists in the other Hubble video said was a possibility. They claimed it depended on it's composition.

    Also, Earth will pass though the comets debris field at the very least, in mid-January 2014.
    Last edited by rtsredux; 2013-Jul-22 at 10:56 PM. Reason: typo

  28. #57
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    Quote Originally Posted by rtsredux View Post
    one of the commenter's of that video brought up a good point imo.

    Why did the ancients all across the planet see comets as being a sign of doom?

    Here is an interesting article about that.

    Comets have inspired dread, fear, and awe in many different cultures and societies around the world and throughout time. They have been branded with such titles as "the Harbinger of Doom" and "the Menace of the Universe."

    They have been regarded both as omens of disaster and messengers of the gods. Why is it that comets are some of the most feared and venerated objects in the night sky? Why did so many cultures cringe at the sight of a comet?

    http://www.nasa.gov/mission_pages/de...ncient_prt.htm
    These things can be scary, no doubt. But, it does not mean every such instance leads to doom. In this case, we are sufficiently knowledgeable to know that we are okay. So, the assertion that we are at risk of ISON is incorrect. Not to say that mitigation means should not be encouraged. That's another topic.

  29. #58
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    Quote Originally Posted by rtsredux View Post
    one of the commenter's of that video brought up a good point imo.

    Why did the ancients all across the planet see comets as being a sign of doom?

    Here is an interesting article about that.

    Comets have inspired dread, fear, and awe in many different cultures and societies around the world and throughout time. They have been branded with such titles as "the Harbinger of Doom" and "the Menace of the Universe."

    They have been regarded both as omens of disaster and messengers of the gods. Why is it that comets are some of the most feared and venerated objects in the night sky? Why did so many cultures cringe at the sight of a comet?

    http://www.nasa.gov/mission_pages/de...ncient_prt.htm
    These things can be scary, no doubt. But, it does not mean every such instance leads to doom. In this case, we are sufficiently knowledgeable to know that we are okay. So, the assertion that we are at risk of ISON is incorrect. Not to say that mitigation means should not be encouraged. That's another topic.

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    Quote Originally Posted by rtsredux View Post
    Here's that video
    http://www.youtube.com/watch?v=skWt9...ature=youtu.be

    they didn't take into account that the comet might break up after reaching perihelion, which the scientists in the other Hubble video said was a possibility. They said it depended on it's composition. Also, Earth will pass though the comets debris field at the very least mid January 2014.
    The debris field will be no more than dust, that, it has been suggested will effectively float down through the atmosphere i believe. I don't think that there is anything to worry about.

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    How close to perihelion it is if and when it breaks up may be important from an orbital mechanics point of view. The deeper in the gravity well it is, the more any thrusting action will affect its trajectory due to the Oberth Effect.
    Et tu BAUT? Quantum mutatus ab illo.

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