About Jayendra Upadhye Expertise 1 - General questions on most astronomy topics such as:-
Solar system, Cosmology, Black holes, Quasars, Dark matter etc.
2 - General questions about the geologies of planets.
3 - General questions about Orbits and laws governing them.
4 - General questions about rockets / spaceships
5 - General questions about stellar interiors and supernovas.
Experience I was an askme.com expert rated no#1 for quite some time - and was top ten there by the time it closed - in Astronomy and general science categories.
Education/Credentials Bachelor of Engg. (Electrical engg), Maharaja Sayajirao university of Baroda, Gujarat, India.
Awards and Honors None to write about except the askme rating if it is any worth!
Question How long would it take the super massive black hole at the center of our galaxy that has begun to feed to completely consume our galaxy?
Answer Hi,
I really dont know why people are so misled on black holes.
Take the elementary case of a planet orbiting a red giant star.
The giant one day suddenly goes supernova.
leaving behind a black hole.
As the star shed about 10-20 percent of its mass in a planetary nebula in its last days on the red giant path, the planet's orbit is unaffected as long as the shell of gas is enclosed in the planet's orbit.
Once it crosses the orbit, the planet suddenly is unburdened of the gravitational pull of the central star by 10 to 20%!! As gravitational intensity inside shells is zero. (Newtonian calculus will show you that.
The planet then spirals away into a new orbit further off.
Now the central star has become a black hile. BUT ITS MASS HAS NOT ALTERED ANY MORE.
That means the star continues its new expanded orbit unhindered.
Gravitational attraction is inversely proportional to distance from the stellar center.
In black holes, the surface of the star resides in the event horizon (inside the shwazchild's radius and so it collapses into a singularity.
But outside, at the orbital peripheri of the planet, it makes no difference if the star further expanded again into a giant, or became a white dwarf, or a neutron star or a black hole, as long as its mass remained largely unaltered!
THIS applies in general to the black hole in the galactic hub.
The stars lazily orbit it at a safe distance.
The globular clusters in the halo go about bobbing up and down the galactic plane, in their polar orbits.
occasionally a stray star gets injested and a colossal beam of energy emerges at the poles of the rotating accretion disk.
But that is about all that happens.
There are few absolutes in the universe. (The temperature of the CMB IS ONE) And black holes are just one of many type of stars.
The universe and the galaxies take them in their stride.
