Planets can form in the galactic center

Sep 11, 2012
In this artist's conception, a protoplanetary disk of gas and dust (red) is being shredded by the powerful gravitational tides of our galaxy's central black hole. Credit: David A. Aguilar (CfA)

(Phys.org)—At first glance, the center of the Milky Way seems like a very inhospitable place to try to form a planet. Stars crowd each other as they whiz through space like cars on a rush-hour freeway. Supernova explosions blast out shock waves and bathe the region in intense radiation. Powerful gravitational forces from a supermassive black hole twist and warp the fabric of space itself.

Yet new research by astronomers at the Harvard-Smithsonian Center for Astrophysics shows that planets still can form in this cosmic maelstrom. For proof, they point to the recent discovery of a cloud of hydrogen and helium plunging toward the galactic center. They argue that this cloud represents the shredded remains of a planet-forming disk orbiting an unseen star.

"This unfortunate star got tossed toward the central black hole. Now it's on the ride of its life, and while it will survive the encounter, its won't be so lucky," said lead author Ruth Murray-Clay of the CfA. The results are appearing in the journal Nature.

The cloud in question was discovered last year by a team of astronomers using the Very Large Telescope in Chile. They speculated that it formed when gas streaming from two collided, like windblown sand gathering into a dune.

Murray-Clay and co-author Avi Loeb propose a different explanation. retain a surrounding disk of gas and dust for millions of years. If one such star dived toward our galaxy's central black hole, radiation and gravitational tides would rip apart its disk in a matter of years.

They also identify the likely source of the stray star - a ring of stars known to orbit the at a distance of about one-tenth of a light-year. Astronomers have detected dozens of young, bright O-type stars in this ring, which suggests that hundreds of fainter Sun-like stars also exist there. Interactions between the stars could fling one inward along with its accompanying disk.

Although this protoplanetary disk is being destroyed, the stars that remain in the ring can hold onto their disks. Therefore, they may form planets despite their hostile surroundings.

As the star continues its plunge over the next year, more and more of the disk's outer material will be torn away, leaving only a dense core. The stripped gas will swirl down into the maw of the black hole. Friction will heat it to high enough temperatures that it will glow in X-rays.

"It's fascinating to think about planets forming so close to a black hole," said Loeb. "If our civilization inhabited such a planet, we could have tested Einstein's theory of gravity much better, and we could have harvested clean energy from throwing our waste into the black hole."

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User comments : 17

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cantdrive85
1.3 / 5 (14) Sep 11, 2012
"and we could have harvested clean energy from throwing our waste into the black hole."

Theoretical physicists come up with the most asinine comments and hypotheses, yet somehow most still consider them scientists. Rubes!
Bowler_4007
5 / 5 (1) Sep 11, 2012
"and we could have harvested clean energy from throwing our waste into the black hole."

Theoretical physicists come up with the most asinine comments and hypotheses, yet somehow most still consider them scientists. Rubes!

Theoretical physicists come up with new ideas and maths which could become science, and lab workers do the same but with chemicals and stuff, now i'm sure you'd call a lab worker a scientist but why not a theoretical physicist? They both do essentialy the same thing 'explore new possibilities'
Fleetfoot
5 / 5 (9) Sep 11, 2012
Even scientists are allowed a sense of humour. You should learn to distinguish what the astrophysicists (not "theoretical physicists") said in their actual paper from what they put in a press interview aimed at laymen before posting such "asinine comments":

http://arxiv.org/abs/1112.4822
kevinrtrs
1 / 5 (17) Sep 11, 2012
Planets can form in the galactic center

Beautifully misleading heading if ever there was one. The only clear observation is that a cloud of dust is heading into the galactic center. Nothing else. The inference of planet formation is sheer speculation as per usual becuase there hasn't been ANY previous observational experience of planet formation recorded in the whole of human history. Especially from a cloud of dust.
The researchers should tone down their optimism that they've discovered any such planetary formation and simply remain humble by disclosing their WISH that it was so.
cantdrive85
1 / 5 (11) Sep 11, 2012
Astrophysicists are theoretical physicists! It is NOT a hard science, so to speak.
Anda
4.5 / 5 (6) Sep 11, 2012
"If our civilization inhabited such a planet, we could have tested Einstein's theory of gravity much better, and we could have harvested clean energy from throwing our waste into the black hole."
... there would not be such civilisation...
Fleetfoot
4.6 / 5 (9) Sep 11, 2012
Astrophysicists are theoretical physicists! It is NOT a hard science, so to speak.


It is obvious from the article that this work is primarily observational, not theoretical, and given that the analysis is numerical, it is 'hard' science.
Fleetfoot
5 / 5 (9) Sep 11, 2012
Planets can form in the galactic center

Beautifully misleading heading if ever there was one. The only clear observation is that a cloud of dust is heading into the galactic center. Nothing else. The inference of planet formation is sheer speculation as per usual ...


Why not read the paper (cited in my previous reply) instead of merely speculating on what it may or may not have shown.
flicktheswitch
4.8 / 5 (5) Sep 11, 2012
Planets can form in the galactic center

Beautifully misleading heading if ever there was one. The only clear observation is that a cloud of dust is heading into the galactic center. Nothing else. The inference of planet formation is sheer speculation as per usual ...


Why not read the paper (cited in my previous reply) instead of merely speculating on what it may or may not have shown.


Ummm... because Kev specialises in avoiding reading anything that may introduce new knowledge or conflict with his existing fixed and immutable beliefs.

If we could quantify his self-referential intransigence physics could use him as a standard unit of measure.
Torbjorn_Larsson_OM
5 / 5 (5) Sep 11, 2012
"The inference of planet formation is sheer speculation as per usual becuase there hasn't been ANY previous observational experience of planet formation recorded in the whole of human history."

'The inference of sedimentation is sheer speculation as per usual because there hasn't been ANY previous observational experience of sedimentation recorded in the whole of human history.'

'The inference of fossilization is sheer speculation as per usual because there hasn't been ANY previous observational experience of fossilization recorded in the whole of human history.'

'The inference of fertilization is sheer speculation as per usual because there hasn't been ANY previous observational experience of sperm meeting egg inside an uterus recorded in the whole of human history.'

Creationists shouldn't comment on science, it is hilarious to see.

Given that this material derives from a protoplanetary disk and given that those are observed to form planets, it is yet another successful test.
OckhamsRazor
5 / 5 (6) Sep 11, 2012
Kevin - Why do you have such a hard time believing that planets can form from dust when a lifeform so simple in comparison, such as a human being, was apparently formed from dust? Your God can make people out of dust but not planets? If anything, you're arguing against the 'logic' of your own religion rather than the logic of science.
Lizard_
not rated yet Sep 12, 2012
Just keep an eye out for the Puppeteer fleet, that's all I've got to say.
Hengine
1 / 5 (2) Sep 12, 2012
Can't we just harvest energy by throwing our waste into the sun?
seb
not rated yet Sep 12, 2012
Can't we just harvest energy by throwing our waste into the sun?


Why, we might even be able to harvest energy from the sun without throwing anything into it! I wonder if we'll ever figure out how to tap that sourc.. oh wait..
rkolter
not rated yet Sep 12, 2012
Even scientists are allowed a sense of humour. You should learn to distinguish what the astrophysicists (not "theoretical physicists") said in their actual paper from what they put in a press interview aimed at laymen before posting such "asinine comments":

http://arxiv.org/abs/1112.4822


THIS.
antialias_physorg
5 / 5 (5) Sep 12, 2012
Kevin - Why do you have such a hard time believing that planets can form from dust

He believes the Earth (and the universe) is 4000 years old - and he's already having trouble fitting all these inconvenient palaeontological findings into that timeframe. Imagine how hard it would be for him to fit the formation of a planet into that timeframe other than by "and then someone snapped their fingers and magic happened".
Torbjorn_Larsson_OM
5 / 5 (3) Sep 12, 2012
Creationist random poofing is so hilariously absurd.

We *know* that most of natural processes, however contingent, are deterministic and even selective, such as biological and chemical processes.

How else do you get water, if not H2 and O2 are chemically selected for reaction by free energy constraints? You wouldn't have oceans if creationist random chemistry, "we have no mechanism and so no constraints - it is all magical poofs", was present!