(Yeah, I’m guessing that’s not what you meant, sorry I am a pedant I’m afraid.)

The Anvil of Stars wikipage doesn’t actually state that the final “Leviathan” planetary system includes a brown dwarf – but from memory I’m fairly sure it does.

Hmm.. On checking the text I find this :

“I we have one question,” Eye on Sky said. “Is this planet natural or artificial?”
“Both,” Salamander said. “Once it was a small star. We have been changing it for thousands of years. First it was used as an energy and fuel source. Now, the easiest answer would be to say that it is artificial.”
- Page 357, Anvil of Stars Greg Bear, Legend, 1992.

That’s referring to the fourth planet of the Leviathan system dubbed Sleep by the Humans btw.

I guess a brown dwarf could, at a stretch, be described as a small star. Surely it’d be easier to transform a brown dwarf into a world than a red dwarf even given god-like alien technology?

I should go hang out there, I’m so sick of winter XD

But surely that’s misleading. If you were to view the earth from space you’d get about 255K ? So it’s much hotter than earth…

jules

PS. For more about “hot high pressure ices” see :

http://en.wikipedia.org/wiki/Ice#Phases

Which answers the riddle of what ice, our Moon and Venus have in common – phases!

The Anvil of Stars wikipage doesn’t actually state that the final “Leviathan” planetary system includes a brown dwarf – but from memory I’m fairly sure it does.

“Megas is on the borderline. It’s either a very warm planet or a very dim brown dwarf .. [snip] .. it’s five times the mass of Jupiter and one thirtieth themass of Nemesis.”
- Page 82, Nemesis, Isaac Asimov, Bantam Books, 1990.

Which – despite the ambiguious description there – would seem to make “Megas” only a superjovian exoplanet because about 13 Jovian masses is required for brown dwarfdom as I understand things.

For more about Bear’s novel Anvil of Stars see:

http://en.wikipedia.org/wiki/Anvil_of_Stars

but WARNING – contains SPOILERS!

That’s a novel I’d strongly recommend too with some of the best aliens I’ve ever read.

@38. MTU :

I suggest they call the eighth brown dwarf they detect (assuming they find another) “Snow White” so there’s Snowwhite & the seven other (brown)dwarfs.

Incidentally, the nickname “Snow White” already belongs to another intermediate planet class body – the ice dwarf world “Snow White” or 2007 OR10 which is the fifth largest ice dwarf planet and is half Pluto’s size.

See :

http://www.eurekalert.org/pub_releases/2011-08/ciot-caf082211.php

Although it seems the name “Snow Red” would actually have been more fitting there – perhaps a renaming to that is now called for!

Not that giving the same name to two duiffrnt things is necessarily a cardinal sin anymore – after all, Hydra is both the largest constellation and one of Pluto’s many small moons.

.. then layers of hot (high pressure) ice down beneath that ocean making up much of their internal structures ..

See :

http://en.wikipedia.org/wiki/Brown_dwarf

for more about brown dwarfs.

See :

http://en.wikipedia.org/wiki/Gliese_436_b

for “hot ice” exoplanet Gliese 436 b which is probably one of many such worlds.

Plus see :

http://en.wikipedia.org/wiki/Nemesis_(Isaac_Asimov_novel)

for Asimov’s Nemesis – the novel not his worst enemy!

Note from there :

Interestingly, the planetary system in the book included a Jovian planet named Megas in a very short-period orbit about its primary star. (Erythro is a moon of Megas.) This was a radical idea in 1989, but was vindicated with the discovery of the first extrasolar planet orbiting a sun-like star (51 Pegasi) in 1995, dubbed “Bellerophon”.

Hmm.. I’m pretty sure I recall Megas being a brown dwarf not a superjovian so I’ll have to check that. I can vouch for that novel being a great read too.

I suggest they call the eighth brown dwarf they detect (assuming theyfuid another) “Snow White” so there’s Snowwhite & the seven other dwarfs.

Great write up there BA too.

@29. Baramos : “So they aren’t really stars but certainly much bigger than gas giants…I guess they could call them ultra super gas giants or something!”

Well brown dwarfs are intermediate boarderline objects between stars and planets. They’ve often been dubbed “failed stars” but “really successful Jupiters” does seem equally apt.

@ 33. Steve Morrison :

“I can see a sci-fi author having a field day with one of these.”
An SF writer already did, over fifty years ago. Georgi Gurevich wrote a story in Russian called “Infra Draconis” which postulated something very much like this; an English translation is collected in the anthology Soviet Science Fiction, with an introduction by Isaac Asimov. (ISBN-13 is 978-0020-16550-7 if anyone is interested in running down a copy.)

Thanks – I haven’t heard of that one.

Isaac Asimov himself has written stories including brown dwarfs as part of the settings – his ‘Nemesis’ novel features one closer than Proxima Centauri in the eponymous star system of red dwarf, brown dwarf and earth-like moon. Pretty sure Greg Bear had a (fictional) brown dwarf – an inhabited one even in the final star system reached in Anvil of Stars too.

@10. Jason : “Is it possible to find liquid water on these? Or would it just be water vapor? Is it possible to have a layer, some depth down that is water?

It seems likely although even more probable is a layer or two of “hot ice” types of solid H2O that form even at very high temperatures under immense presures.

For some cold old brown dwarfs, there may be an ocean under a thick atmosphere, then layers of hot ice down making up much of tehinetrabnl structures just as there are on massive exoplanets incl. some “super-Earths” (eg.Gliese 436 b) although I’m not 100% certain of this for brown dwarfs.

——

* (WISE guys & girls – but then girls can be guys too metaphorically, right?

There are ideas like MOND which claim the discrepancies are miscalculations or mistakes in understanding gravity, but currently dark matter is the most accepted hypothesis as it seems to fit cleanly with other observations while no other proposals do.

As a lay person, I used to have difficulty with the seemingly invented idea of dark matter but reading more about particles and particle creation at the beginning of everything made it easier to see how neutral, mass-bearing particles which don’t interact with photons could be possible. It helps dark matter seem ordinary

This brown dwarf is probably first-generation, because otherwise radioactive decay alone might keep it hotter than that. Planets/dwarfs in the 1-20 Mj range would have a similar radius as jupiter due to gravity’s effect on the cold gas, so the mass to surface area ratio is huge.

I can see a sci-fi author having a field day with one of these.

An SF writer already did, over fifty years ago. Georgi Gurevich wrote a story in Russian called “Infra Draconis” which postulated something very much like this; an English translation is collected in the anthology Soviet Science Fiction, with an introduction by Isaac Asimov. (ISBN-13 is 978-0020-16550-7 if anyone is interested in running down a copy.)

I can see a sci-fi author having a field day with one of these.