Clouds made of droplets of molten iron have been detected on

Clouds made of droplets of molten iron have been detected on

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Toaster

Original Poster:

2,940 posts

200 months

Wednesday 4th November 2015
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Clouds made of droplets of molten iron have been detected on a sunless world 75 light years from Earth.

Edinburgh University astronomers find sunless world

http://www.bbc.co.uk/news/uk-scotland-edinburgh-ea...

How intriguing smile

marksx

5,121 posts

197 months

Wednesday 4th November 2015
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Heavy rain predicted.

Eric Mc

122,861 posts

272 months

Wednesday 4th November 2015
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How was it detected. Without a star to illuminate it, it must be very, very dark.

RobDickinson

31,343 posts

261 months

Wednesday 4th November 2015
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I assume it will shine in IR?

marksx

5,121 posts

197 months

Wednesday 4th November 2015
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This is from another article on the finding:

A team led by the University of Edinburgh used a telescope in Chile to study the weather systems in the distant world - known as PSO J318.5-22 - which is estimated to be around 20 million-years-old.

Researchers captured hundreds of infra-red images of the object as it rotated over a 5-hour period. By comparing the brightness of PSO J318.5-22 with neighbouring bodies, the team discovered that it is covered in multiple layers of thick and thin cloud. These cause changes to the brightness of the distant world as it rotates, the team says.

Toaster

Original Poster:

2,940 posts

200 months

Wednesday 4th November 2015
quotequote all
http://www.ed.ac.uk/news/2015/distantworld-031115

'Temperatures inside clouds on PSO J318.5-22 exceed 800°C'

glazbagun

14,483 posts

204 months

Wednesday 4th November 2015
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I would have suggested Planet Scotland with it being sunless, but it does seem pleasantly warm by comparison.

Eric Mc

122,861 posts

272 months

Thursday 5th November 2015
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marksx said:
This is from another article on the finding:

A team led by the University of Edinburgh used a telescope in Chile to study the weather systems in the distant world - known as PSO J318.5-22 - which is estimated to be around 20 million-years-old.

Researchers captured hundreds of infra-red images of the object as it rotated over a 5-hour period. By comparing the brightness of PSO J318.5-22 with neighbouring bodies, the team discovered that it is covered in multiple layers of thick and thin cloud. These cause changes to the brightness of the distant world as it rotates, the team says.
What "neighboring bodies"? Is this planet orbiting a star or not?

Toaster

Original Poster:

2,940 posts

200 months

Thursday 5th November 2015
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Eric Mc said:
What "neighboring bodies"? Is this planet orbiting a star or not?
There is no Star

https://www.ifa.hawaii.edu/info/press-releases/Lon...

"We have never before seen an object free-floating in space that that looks like this. It has all the characteristics of young planets found around other stars, but it is drifting out there all alone,” explained team leader Dr. Michael Liu of the Institute for Astronomy at the University of Hawaii at Manoa. “I had often wondered if such solitary objects exist, and now we know they do.”

'neighbouring bodies' are not nearby bodies

Edited by Toaster on Thursday 5th November 09:14

Eric Mc

122,861 posts

272 months

Thursday 5th November 2015
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How "neighbouring" are they?

If they aren't connected in any way with this drifting planet i.e. not part of the same solar system, then drawing comparatives with it sounds a bit pointless. And I would assume that the "neighboring bodies" must be stars as opposed to more drifting planets.

It all sounds a bit woolly to me.

2hoots

57 posts

109 months

Thursday 5th November 2015
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First post.

Interesting and there's an article on Space.com that says this about Orphan planets: "The discovery of a starless alien planet would not be shocking, at least not anymore. In the last year or so, astronomers have spotted a number of such orphan worlds — so many, in fact, that some scientists think parentless planets are the rule rather than the exception.

One 2011 study, for example, estimated that rogue worlds outnumber "normal" planets with obvious host stars by at least 50% throughout the Milky Way. If that's the case, the galaxy that includes Earth probably also hosts billions of orphan planets.

And gas giants may be in the minority among these solitary wanderers, researchers say."

Eric Mc

122,861 posts

272 months

Thursday 5th November 2015
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The problem for orphan planets is that the only source of energy on the planet will be internal heat generated through radioactive decay of its core. It may not remain hot enough, long enough to allow life to get going. And it will receive very little light - part from the glow of distant stars.

They do sound like fascinating worlds - but not very hospitable.

Toaster

Original Poster:

2,940 posts

200 months

Thursday 5th November 2015
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It is calculated that, for an Earth-sized object at a kilobar hydrogen atmospheric pressures in which a convective gas adiabat has formed, geothermal energy from residual core radioisotope decay will be sufficient to heat the surface to temperatures above the melting point of water

Id loved to have written that however https://en.wikipedia.org/wiki/Rogue_planet


Hugo a Gogo

23,383 posts

240 months

Thursday 5th November 2015
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so exciting rogue planet or dull failed star?

Toaster

Original Poster:

2,940 posts

200 months

Thursday 5th November 2015
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Hugo a Gogo said:
so exciting rogue planet or dull failed star?
Good question, it is being described by the scientists as a planet but as you are probably aware it wasn't until 2006 that the IAU provided a scientific definition of what a planet is

"The IAU members gathered at the 2006 General Assembly agreed that a “planet” is defined as a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit."

https://www.google.com/url?q=http://www.iau.org/st...

Its an interesting document

Hugo a Gogo

23,383 posts

240 months

Thursday 5th November 2015
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so by definition this isn't a planet

Eric Mc

122,861 posts

272 months

Friday 6th November 2015
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I think we get a bit hung up on definitions sometimes.

Hugo a Gogo

23,383 posts

240 months

Friday 6th November 2015
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effectively a 'rogue/orphan planet' can be anything up to a brown dwarf, so it could have enough heat and energy within it to have liquid water for instance (or iron!) and an atmosphere, just not enough mass to gravitionally collapse and started fusion

no light of course, but no harmful solar radiation either, so doesn't need the magnetic fields to protect any life

Toaster

Original Poster:

2,940 posts

200 months

Friday 6th November 2015
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Hugo a Gogo said:
so by definition this isn't a planet
Reading that document it states our solar system, in which case it isn't defining this find

Hugo a Gogo

23,383 posts

240 months

Friday 6th November 2015
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true

the wiki page for exoplanets has this note:
"This definition is drawn from two separate IAU declarations; a formal definition agreed by the IAU in 2006, and an informal working definition established by the IAU in 2001/2003 for objects outside of the Solar System. The official 2006 definition applies only to the Solar System, whereas the 2003 definition applies to planets around other stars. The extrasolar planet issue was deemed too complex to resolve at the 2006 IAU conference."