Planets may lurk in harshest environments. Not that Novell NetWare server you can't unplug – black holes Giant planets up to ten times the mass of the Earth can form around violent supermassive black holes without the need for stars, according to research accepted into The Astrophysical Journal. "With the right conditions, planets could be formed even in harsh environments, such as around a black hole," Keiichi Wada, first author …
But Life ? Even planets are likely going to have a hard time not smashing into each other. I really don't see that kind of environment as being anywhere near a place where Life could take hold.
On the other hand, with all the stuff that's in the area, water is likely to be there as well, so those planets could very well have water. If they are massive rocky planets, there could be water deep down, shielded by dozens of meters of rock, where some form of bacterial life could subsist.
Since the idea is that planets form in the accretion disk, they will orbit the black hole and not get sucked in. That means that they'll be around for the next wave of matter that falls in. Except that, if that next wave is in the form of an incoming star, then all bets are off as to the stability of the planets' orbits. They'll either get ejected from the system (at high velocity), or they'll be dragged into the singularity, ripping apart along the way.
Either outcome means the death of any life that may have taken hold.
Not a nice place to be born, to say the least.
You could have gravitational squeezing of the planet as a source of energy and I'm sure there would be plenty of high frequency radiation being emitted from the accretion disc amongst others. Might make for some interesting forms of life.
Mines the one with a Dweller book in the pocket.
But that would on no way be in the ball park of the energy we get from the sun. Orders or magnatude off.
If you are going to reach..
You end up throwing any sense and science out. "Life coykd be anywhere in any type." Is a valid statement but has no scientific data to back it up. Currently we have one type of life... even if theoretical crystal creatures could live on titan or clockwork cockroaches in a subterranean gravity wobble warmed superearth.
"But that would on no way be in the ball park of the energy we get from the sun. Orders or magnatude off."
I'm not sure what you're saying here. The problem is there is too much energy around a black hole. (The paper says 1010-12L⊙ - with planet formation inside 106 AU.) The authors' problem is finding a region cold enough for planet formation to take place, given observational evidence of warm dust. They do that. But it's not inconvertible that the planet could migrate to somewhere slightly warmer - it's a turbulent environment.
I still don't think there'd be life there, but.
Black holes suck in everything, including any energy that might be around.
But only at the event horizon. Imagine a photon generated at a point somewhere in the accretion disk. If it happens to be emitted directly towards the black hole it will end up being sucked in (assuming it doesn't strike anything else first). If it is emitted in a direction that will just miss the event horizon it will swing around the black hole and maybe even head back almost towards the point where it was generated. If it is emitted off to one side it could pass round the black hole and head out into space, possibly even appearing to a distant observer as if it had passed through the black hole. But if it is emitted directly away from the black hole then it will escape quite comfortably, even though to an observer higher up the gravity well it will appear to take longer than a simple distance-over-velocity calculation would suggest. So a gamma ray emitted from the accretion disc could end up striking a planet in the outer disc, generating a particle shower and ultimately heat.
(All of the above is a simplistic treatment; the photon's path would also be affected by the frame-dragging effect caused by a spinning black hole.)
They won't "suck in" anything that an object of equivalent mass would suck in. If they sucked in "everything, including all energy that might be around" they would be truly be black and we would have no chance of seeing any evidence that they exist.
Any black hole with enough "stuff" around it to form planets would emit (not the black hole itself, but the stuff orbiting it being heated up) enormous amounts of energy/radiation. Besides, life doesn't necessary need energy from the outside. If a massive planet 10x the size of Earth had Earth or Moon sized moons orbiting it closely, it could be like Jupiter/Europa, which has liquid water in its oceans due to the heat from the tidal forces. Life is just as possible on that black hole moon as it is on Europa, without any sunlight being necessary.
Black holes suck in everything, including any energy that might be around.
Black holes, or rather their accretion disks, are among the most luminous objects we know. The most luminous ones are thousands of times brighter than entire galaxies such as ours. Lack of energy is not the problem here: too much energy at too short a wavelength probably is (life, as we understand it, doesn't do very well in hard-x-ray environments).
There are no stable circular orbits sufficiently close to a black hole. For a Schwarzschild (non-spinning) BH the critical radius is 6GM/c^2, where M is the mass of the object.
The objects they consider in the paper have masses in the range 10^6-10^9 solar masses. A 10^6 solar mass black hole has an innermost stable circular orbit radius of about 0.06au (ie about 1/16th of the Earth's orbital radius, and about 1/7 of the orbital radius of Mercury), while a 10^9 one is about 60au, which is outside the orbit of Pluto by a bit. A light year (ly) is about 63,000au.
The planets which might form around these objects have orbital radii of about 10ly: stable orbits very definitely exist at such radii.
I watched a time lapse film of several stars orbiting a black hole - the orbit was highly elliptic though. If this can happen why not planets? I'd imagine black holes could rob planets from star systems and probably gobble a lot of them up as well. Who would really know if those stars were formed from being close to a black hole or not - many questions here. I know it is realistic to assume no stars and only planets can form around a black hole orbit, but who is to say they couldn't get so massive they'd graduate to star size?
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