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Monster Black Hole Busts Theory
Genocaust writes "A stellar black hole much more massive than theory predicts is possible has astronomers puzzled. Stellar black holes form when stars with masses around 20 times that of the sun collapse under the weight of their own gravity at the ends of their lives. Most stellar black holes weigh in at around 10 solar masses when the smoke blows away, and computer models of star evolution have difficulty producing black holes more massive than this. The newly weighed black hole is 16 solar masses. It orbits a companion star in the spiral galaxy Messier 33, located 2.7 million light-years from Earth. Together they make up the system known as M33 X-7."
Just FYI: after binary comes TERNARY, not trinary. Don't feel bad, though, it's a very common mistake which I myself have made before being corrected.
*Stellar* black holes are black holes that originate from the aftermath of a single star going supernova.
Super-massive black holes like what exist at the center of a galaxy don't have a well understood origin, but it is supposed that if a black hole is created in a region of space with a great deal of matter in the vicinity, it may gobble up a lot of it, adding to its mass until it becomes super-massive.
A stellar black hole that's so big it shouldn't be possible for it to have been created by the usual supernova, and in a region of space sufficiently vacant to rule out the gobbling theory, is what is being puzzled over.
You see? You see? Your stupid minds! Stupid! Stupid!
Another issue is the unlikely chance of paired stars crashing into each other. After one partner blows its top at the end of life, it usually loses some mass such that the distance between them INcreases, making them even less likely to touch or enter friction zones. (Being a black hole by itself does not increase its gravitational pull over a star of the same mass). If they are going to merge, they would more likely do so during the regular life, and we'd see samples of such massive stars. But we don't, mainly because there is an upper limit to the size of a stable star.
Further, large stars have short lives, meaning that the time for friction to rub them closer to each other is shorter.
However, it is true that a collision of two big mid-life stars may itself trigger a supernova because the total mass exceeds a stable size, and thus a very large black hole is formed. This may result in a black hole that *looks* like it came from a star larger than the max stable size of a star because its exceeding the stable limit itself is what triggered the formation of the hole. In short, there may be a limit to stable star size, but not to unstable star size.
Table-ized A.I.
Black holes don't produce x-rays, but the material falling into them does produce x-rays which, since they're produced outside the black hole, can escape.
Words like "produce" and "consume" are bad science words. Mostly used in docudrama style tv shows and movies using snippets of science to achieve an end goal: make more money by scaring the crap out of people. Black holes do not EMIT xrays, or anything else that we know of (although they must be emitting something if you believe like Hawking, that black holes can and do lose mass and eventually dissipate) . Xrays are EMITTED by material (gases) falling into a black hole, being heated as they move and gain density. The additional energy the gas absorbs is enough to have it shoot off in an almost plasma jet fashion. Technically we can not and never will be able to "see" as in observe visible light reflecting off of a black hole and having it be observed with our retina. The only way we can detect a black hole is by: observing occulations of stars/galaxies either in the visible or xray spectrums; calculating masses of quasars or galaxies based on rotational speeds and observed mass index; or touching it and falling in. It's only a matter of semantics though. We see things all the time without having to actually be hit by reflected light; a person walking across a dark room, slightly obscuring the light from the window comes to mind.
IANAAP(I am not an astro physicist) but my understanding of it is that black holes give off a form of radiation called Hawking Radiation. As Hawking Radiation escapes the black hole its mass slowly decreases because (E=mc^2 etc). Eventually the black hole will radiate all of its mass and will have essentially evaporated.
Likely they are referring to Hawking Radiation.
Nah. It's a reasonable question. "stellar" is not necessarily generally thought of as a term of finite measurement outside of Academia.
I'm well aware that a lot of the information that astrophysicists want to know have huge uncertainties. I'm involved in making those measurements.