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Founded January 1970
Julian date: 2457709.16
"Briefly spoken"
THE DAILY ASTRONOMER
Wednesday, November 16, 2016
A Black Hole Pandora
Today we write rapidly. Earth has been spinning so quickly and recklessly that before we knew it, the day was ending about ten minutes before it actually began, or, at least, seemed that way. So, here we are, perched precariously on the edge of a day that is soon to drop into the unsounded oblivion and the DA is still coagulating in the ghost universe. Well...not for much longer.
In this article, we'll address only one Pandora parchment as we are microscopically short on time. However, at some point, we'll have to dig into the vessel much more deeply, especially if we want to meet our 100 Pandora goal by August.
Pandora Parchment # 7: "I learned that time slows down for you if you are approaching a black hole. Also, when you reach a black hole's edge, or event horizon, time can stop. If that is so, how can a black hole devour anything?"
S.W, Harrison, ME
Greetings!
Yes, time does slow down as one approaches a black hole, but that dilation is relative to an observer well away from this black hole. Let's pretend that I am sitting safely on a space vessel that is describing a wide orbit around a black hole. You, alas, have volunteered to operate a vessel that is careening toward the black hole. (Incidentally, that was not a particularly safe choice, but you seemed so eager, I didn't want to say anything.)
You accelerate as you approach the black hole and consequently you experience time dilation. Time slows down on vessels that are moving quickly. You are also experiencing gravitational time dilation. Time slows down in gravity fields.* As you sit in the vessel that is moving inexorably toward the black hole, it will seem to you as if time is progressing normally. I, on the other hand, see you appear to slow down because of the time dilation.
Black holes affect time as well as space. After all, space and time are two aspects of the space-time continuum.
You will eventually be drawn into the black hole. Now, before you panic, realize that the black hole's intense tidal forces will rip you into your subatomic particles long before you reach the event horizon, thereby sparing you the horror of actually "entering" the black hole. I, being the cowardly -but utterly sensible- outside observer, will never see you enter this black hole. However, to you, very little time will have passed and the black hole will devour your material just as it consumes other material.
Gravitational time dilation profoundly affects the region just outside a black hole. However, it doesn't prevent a black hole from drawing material into itself. A black hole will feed voraciously provided it has an abundance of material around it.
*Gravitational time dilation even affects GPS systems here on Earth, because the satellites in orbit around the planet are experiencing a different time stream than the devices on Earth's surface.