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NGC 4051 is a spiral Sifert galaxy in the constellation Ursa Major, at about 48 Mly from earth. It covers about 5 x 4 arcminutes of the night sky The core of this galaxy contains a supermassive black hole. Data from the Liverpool Telescope, La Palma (2 m aperture and 0.28 "/pixel resolution)
I have a question about the formation of the singularity which supposedly lies at the center of a black hole. A singularity could form for example by the collapse of the core of a massive star after it has depleted its fuel. However, once the core has collapsed down to the Schwarzschild radius, time, from the viewpoint of an observer at a distance, comes to a hold. This is a consequence of the gravitational time dilation which is implied by the general theory of relativity. An event that would last, say, a second for an observer at the Schwarzschild radius, would last an infinite amount of time for a distant observer. Therefore, once the core has collapsed down to the Schwarzschild radius further contraction should, according to the distant observer, take an infinite amount of time. Therefore the singularity can never be formed. What is wrong with this line of reasoning?
M87 galaxy with the relativistic jet fired from the super massive black hole 27/02/2017 01:19 (55.000.000 light years) GSO 0.20 m Sky-Watcher NEQ-5 Pro SynScan mount QHY5L-IIC + IR cut filter f: 1000 mm f/5 Matteo Vacca Milis, Italy http://vaccamatteo.weebly.com/ https://www.astrobin.com/users/matteovacca/
I have a question, imagine a Galaxy with a supermassive black hole smack in the middle, with a mass of a billion suns, devowering stars at an incredible rate and relatively growing as it consumes stars. A black hole that large in the center of our galaxy, “Sagittarius A” it’s location is believed to be, in the densest part of our galaxy (I mean concentration and proximity of stars) would be swallowing up stars at an enormous rate would it not?. Astronomers say it is possible that all, most, many? Galaxies have a supermassive black hole at their cores, let’s assume this is fact, eventually an entire galaxy can be consumed by a black hole that size. The more it consumes, the greater it’s gravitational pull, it eventually grows exponentially until the whole galaxy is snuffed out?. Having said that, there surely must be examples somewhere of galaxies in the process of being swallowed up, in their final death throws, the remnants of spiral arms and the few millions of stars left on their final plunge into blackness and infinite, invisible density. Or, supermassive black holes may well be a relatively new phase in a galaxies life cycle? are we living at the point where these gargantuan black holes are coming into existence, and maybe it will be billions of years more before galaxies begin to fall prey to their own black holes?. Are there any examples of galaxies much older than ours where evidence shows they are being consumed slowly? Something as massive, and destructive, as a black hole with a billion star mass, smack in the middle of a galaxies densest region must eventually become a runaway, growing exponentially and consume an entire galaxy, would it not?. Is it possible that our present stelliferous age will meet its end by way of ever expanding black holes?. I would love to hear your thoughts!
Hi, im Kez and have heaps of questions about a hypothesis I came up with hopeing some one will help with some of these and educate me a lot. What math would I nerd to learn to try to calculate the size of a black hole with a mass several times that of earth? If a small black hole were stationary relative to the sun close to our solar system would the orbit of earth be likely to create an eclipse with a distant star and if so at what frequency and would current technology be able to conclusively measure an observation? Also what math do I need to figure this out? Anyone know anyone doing work on this or if it was previously hypothesised? Disproved? Anyone with anything that may educate me on this topic would be awesome and even general comments, thoughts, I'm a real noob but genuine interest in astrophysics, quantum physics heaps of stuff. Any knowledgeable contacts for discussion. Cheers!!!! All
http://www.bbc.co.uk/news/science-environment-38937141 says " There is optimism that observations to be conducted during 5-14 April could finally deliver the long-sought prize. " But its full moon and now cloud will have been ordered