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View Full Version : An Oort planet.. what would you like to see



baric
2011-Feb-17, 12:37 AM
This discussion isn't about Tyche, specifically, but about what we think would be an ideal type of body to find in the Oort cloud --- assuming one exists.


A brown dwarf? A super-Jupiter? A super-Earth?


If I could choose, I think I would like to see a super Earth.. maybe 4-5 Earth masses. It's the missing link in our system and seeing how silicates respond to high pressures would go a long way towards improving our models of exoplanets.

marsbug
2011-Feb-17, 12:51 AM
I'd vote for a brown dwarf/superjupiter, but thats just a personal preference; the same way superearths are the missing link in planetary evolution cold, low mass, brown dwarfs are something of a missing link in stellar evolution. The chance to study one up close could inform our understanding of stellar systems in a more general way than a superearth.

baric
2011-Feb-17, 01:12 AM
hmm, a brown dwarf with a tidally locked super-earth might be the best of BOTH worlds... << terrible double entendre

IsaacKuo
2011-Feb-17, 07:39 AM
A substellar mass black hole. That would be scientifically interesting, to say the least!

Hernalt
2011-Feb-17, 10:40 AM
The following is quoted along the vector of this thought: "How to break down the cyclopean distance between stars using their Oort Clouds as stepping stones, irrespective of how many cryogenically frozen embryos or generation ships that human (or derivative) migration requires."

http://en.wikipedia.org/wiki/Oort_cloud
"hypothesized spherical cloud of comets which may lie roughly 50,000 AU, or nearly a light-year, from the Sun.[1] This places the cloud at nearly a quarter of the distance to Proxima Centauri"
They say that waking up is half your day.

"The Oort cloud is thought to comprise two separate regions: a spherical outer Oort cloud and a disc-shaped inner Oort cloud, or Hills cloud."
It is wise to use the rest room right away before embarking on a significant journey. It may not be the case that the ecliptic Hills Cloud lines up with Alpha Centauri, but sometimes one must use the Houston, Baltimore, etc, beltway.

"the discovery of the object 1996 PW, an asteroid in an orbit more typical of a long-period comet, suggests that the cloud may also be home to rocky objects.[19] Analysis of the carbon and nitrogen isotope ratios in both the Oort cloud and Jupiter-family comets shows little difference between the two, despite their vastly separate regions of origin. This suggests that both originated from the original protosolar cloud,[20] a conclusion also supported by studies of granular size in Oort cloud comets[21] and by the recent impact study of Jupiter-family comet Tempel 1.[22]"
It makes sense to me that on very small / nano scales, individual high metallicity particles are not going to be preferentially attracted towards the central protostar. Of course then, how could they be preferentially attracted to each other? Well, very small gravitational scales, 5 gy and low expectations. There is no finer sight than to see a Love's travel stop in the middle of a Southwest nowhere, because you know they have Subway (usually), which the endocrine system interprets as "guacamole".

"The outer Oort cloud is believed to contain several trillion individual objects larger than approximately 1 km (0.62 mi)[1] (with many billions with absolute magnitudes[14] brighter than 11—corresponding to approximately 20 km (12 mi) diameter)"
Love's travel stops are perhaps 100m x 100m? 200?

In quest of conservative prudence, I hysterically advocate for some kind of rocky body that is not greatly much more than merely sufficiently massive to gravitationally differentiate (see: Ganymede (http://en.wikipedia.org/wiki/Ganymede_%28moon%29)), and which retains sufficient radioactives to maintain ""some"" core heat, and plausibly mantle convection -although radiative transfer will do-, and which has collected a heap of ices -but not hydrogen and certainly not helium-, and has formed a dirty ice shell, which insulates some vanishingly thin layer of liquid ocean, which plays host to some form of starfish who taste of chicken and seaweed that tastes of arugula. If this object has been glancingly struck by another object so as to impart sufficient momentum to generate a quaint magnetic field, all the better. Someone correct me: I believe that galactic cosmic rays would be a greater issue closer to the heliopause than close to the sun.

tnjrp
2011-Feb-17, 10:47 AM
Maybe a little something along the lines of
Yuggoth... is a strange dark orb at the very rim of our solar system... There are mighty cities on Yuggoth—great tiers of terraced towers built of black stone... The sun shines there no brighter than a star, but the beings need no light. They have other subtler senses, and put no windows in their great houses and temples... The black rivers of pitch that flow under those mysterious cyclopean bridges—things built by some elder race extinct and forgotten before the beings came to Yuggoth from the ultimate voids—ought to be enough to make any man a Dante or Poe if he can keep sane long enough to tell what he has seen...
Barring that, anything massive that is not another Jovian would do me fine enough. Nothing wrong with Jovians per se but we've got a couple of those closer at hand already.

baric
2011-Feb-17, 02:58 PM
A substellar mass black hole. That would be scientifically interesting, to say the least!

No kidding. For starters, how could it form?

The biggest problem with finding a nearby black hole is the incredible amount of public hysteria it would create. It would be 2012 times... 2012.

dindyB
2011-Feb-19, 04:52 AM
I would like to see a planet same as Earth where we can live. Scientists suspect that a gigantic planet might be orbiting out in space far beyond the known solar system. Comet trajectories show scientists that something unaccounted for factors in the equation. The presence of a huge planet in deep space would make the numbers add up. The theoretical planet “ Tyche (http://personalmoneystore.com/moneyblog/2011/02/15/new-planet-tyche/)” may become fact, depending on data predicted from a NASA space telescope that could spot it with an infrared camera peering deep into space.

baric
2011-Feb-19, 07:54 PM
I would like to see a planet same as Earth where we can live.

It would be too cold... much, much colder than Pluto! :P

caveman1917
2011-Feb-27, 03:35 AM
How about a substellar size black hole orbited by an earth-like planet which is kept at the right temperature due to tidal heating?

Ara Pacis
2011-Feb-27, 09:06 AM
I'd like to see a super-earth terrestrial type of object. I mean, who wouldn't want to see a dwarf planet bigger than Earth.

I wonder, how far might Jupiter fling out a sizable planet mass object from during the days of planet mass object formation in the solar system, and at what might it's orbit look like. Would it have a long period highly elliptical orbit that might have a perihelion in the neighborhood of Jupiter's orbit and an aphelion much farther out?

Ilya
2011-Mar-03, 08:11 PM
A substellar mass black hole. That would be scientifically interesting, to say the least!
If you are going that way... then my choice is abandoned alien fortress!

baric
2011-Mar-03, 08:42 PM
If you are going that way... then my choice is abandoned alien fortress!

That's no moon...

JackWindu
2011-Mar-04, 08:10 PM
I'd like to see a Brown Dwarf that is orbited by a Jupiter sized planet that has an Earth sized moon.

Hungry4info
2011-Mar-05, 05:24 AM
I'd like to see a Brown Dwarf that is orbited by a Jupiter sized planet that has an Earth sized moon.

You're just trying to throw our planet formation models into chaos, eh? ;P

neilzero
2011-Mar-06, 08:00 PM
How about an Pluto size planet with a 10 meter neutronium core. The surface gravity could be up to a thousand times Earth surface gravity. I suppose the core would be surrounded by a thick layer of neutrons and white star stuff, but likely a negligible number of free neutrons would reach the surface since free neutrons decay into protons, electrons and ? Neil

Hernalt
2011-Mar-28, 11:38 PM
Super Earth dead zones (http://www.dailygalaxy.com/my_weblog/2011/03/super-earth-exo-planets-may-exist-as-dead-zones.html)

Van Rijn
2011-Mar-29, 08:16 AM
Super Earth dead zones (http://www.dailygalaxy.com/my_weblog/2011/03/super-earth-exo-planets-may-exist-as-dead-zones.html)

Er, this doesn't make sense to me (quoting from the article):


A simulation of super-Earths between a few times and 10 times Earth's mass suggests that high pressures will keep the core solid, according to Guillaume Morard of the Institute of Mineralogy and Physics of Condensed Matter in Paris, France. Without a magnetic field, the planets would be bathed in harmful radiation, and their atmospheres would be eroded away by particles streaming from their stars.

The present-day Mars is a perfect example of a planet that lost its magnetic field.[snip]

A reasonably thick atmosphere is very effective at protecting the surface from radiation, and a Super-Earth would be far better than Earth or Venus (let alone Mars) at holding onto atmosphere because it has more mass. Mars is a terrible example to compare to a Super-Earth. It undoubtedly lost atmosphere far more easily than a Super-Earth would due to multiple mechanisms because of its small mass. It wasn't just the loss of a magnetic field.

tnjrp
2011-Mar-29, 09:06 AM
Indeed this recent study casts some doubt on the role of a magnetic field in atmosphere retention:
http://www.astrobio.net/exclusive/3856/the-importance-of-being-magnetized

slang
2011-Mar-29, 10:17 AM
Where are your manners, people? :) Welcome to BAUT, dindyB!


I would like to see a planet same as Earth where we can live.

Pretty close to what I would like to see! An Earth analog, captured from a passing star, with all the remnants of its previous inhabitants still on the surface, waiting for us to explore. Maybe in "A Pail Of Air (http://www.google.com/search?q=a+pail+of+air)" situation. :)

tnjrp
2011-Mar-29, 10:22 AM
Oi, I've already called Yuggoth!

Hernalt
2011-Mar-30, 04:50 AM
A reasonably thick atmosphere is very effective at protecting the surface from radiation, and a Super-Earth would be far better than Earth or Venus (let alone Mars) at holding onto atmosphere because it has more mass.
I agree with this. Germane to the OP, for any range of rocky bodies in an Oort cloud, contraction/nuclear-based thermal energy could prevent atmosphere liquefaction for some time. But for comparison's sake, how would the earth's atmosphere fare against galactic cosmic rays (GCR) if it were analogously located in the Oort cloud? Your take on that news piece made me wonder if super earths would be a sort of 'all-terrain' life-supporting rocky body, able to incubate well into interstellar space.

I should have went and found the original article I read a while back.
"The melting curve of iron at extreme pressures: implications for planetary cores" (http://arxiv.org/ftp/arxiv/papers/1010/1010.5133.pdf)
It makes no mention of life and makes no assertion that magnetic fields are critical for atmosphere retention. It may be useful reference in this new Kepler era.

Van Rijn
2011-Mar-30, 05:12 AM
I agree with this. Germane to the OP, for any range of rocky bodies in an Oort cloud, contraction/nuclear-based thermal energy could prevent atmosphere liquefaction for some time. But for comparison's sake, how would the earth's atmosphere fare against galactic cosmic rays (GCR) if it were analogously located in the Oort cloud? Your take on that news piece made me wonder if super earths would be a sort of 'all-terrain' life-supporting rocky body, able to incubate well into interstellar space.

I should have went and found the original article I read a while back.
"The melting curve of iron at extreme pressures: implications for planetary cores" (http://arxiv.org/ftp/arxiv/papers/1010/1010.5133.pdf)
It makes no mention of life and makes no assertion that magnetic fields are critical for atmosphere retention. It may be useful reference in this new Kepler era.

I'm glad the original article didn't throw in those assumptions. I don't know how there could be a world with an Earth-like atmosphere in the Oort cloud, but if there was, it would fare about the same as Earth's atmosphere here.

Van Rijn
2011-Mar-30, 05:21 AM
Indeed this recent study casts some doubt on the role of a magnetic field in atmosphere retention:
http://www.astrobio.net/exclusive/3856/the-importance-of-being-magnetized

Oh, now that's interesting! Though I'd like to see more on the original articles it's based on.

I've been a bit bemused at the assumption (apparently common in science shows) that a magnetic field is more important than gravity in holding onto atmosphere. You also see it come up here in discussions, for instance, about terraforming, where some seem to assume Mars couldn't hold onto an atmosphere for any time at all. My suspicion has been that if it is important, it would be more about the effects on atmospheric composition over the long term, for instance, a bigger loss of hydrogen than oxygen (which is heavier, so won't escape as easily).

Sorry if this is off topic, but that really is an interesting article. Thanks.

Ilya
2011-Mar-31, 02:11 PM
Oi, I've already called Yuggoth!
I am actually surprised there is no minor planet Yuggoth yet.