Comments for "Bad Astronomer - Why do black holes have so much gravity?" Video at VideoSift.com

By blankfist

blankfist (http://blankfist.videosift.com) — Tue, 22 Jul 2008 15:11:20 -0700

I don't trust bald people.

By Zor

Zor (http://cooking.videosift.com/member/Zor) — Tue, 22 Jul 2008 15:30:34 -0700

I don't think that "astronomy/physics for everyone" is a good idea. Abandon hope now that a significant percentage of any sample of humans are going to ever understand what this means.

By kronosposeidon

kronosposeidon (http://kronosposeidon.videosift.com) — Tue, 22 Jul 2008 16:23:54 -0700

Because it's so dinky is what makes it so powerful.

Well, that oughta shut up my girlfriend.

By T-man

T-man (http://tman.videosift.com) — Tue, 22 Jul 2008 17:11:37 -0700

I don't trust people with crotch shots for their avatar.

By budzos

budzos (http://cooking.videosift.com/member/budzos) — Tue, 22 Jul 2008 17:53:08 -0700

Not a great explanation.

By Majortomyorke

Majortomyorke (http://cooking.videosift.com/member/Majortomyorke) — Tue, 22 Jul 2008 21:16:14 -0700

Upvote for the dinky.

By nibiyabi

nibiyabi (http://nibiyabi.videosift.com) — Wed, 23 Jul 2008 00:15:53 -0700

>> ^budzos:
Not a great explanation.

He would lose his target audience if he were to get technical. Someone has to explain this stuff at this level for most people to have any grasp of it at all. In a country (United States) where a majority believes we lived alongside dinosaurs, this guy is the first line of defense.

By SSIops

SSIops (http://cooking.videosift.com/member/SSIops) — Wed, 23 Jul 2008 02:37:24 -0700

I wish this guy was my astronomy teacher. It would be fun to answer "Cause it's dinky" on a test =)

By gwiz665

gwiz665 (http://cooking.videosift.com/member/gwiz665) — Wed, 23 Jul 2008 04:37:35 -0700

Yay, science for everyone.

By Irishman

Irishman (http://cooking.videosift.com/member/Irishman) — Wed, 23 Jul 2008 10:29:30 -0700

>> ^budzos:
Not a great explanation.

It's a perfect explanation, gravity is a function of distance, object is smaller, therefore you can get closer, therefore gravity increases (exponentially).

By honkeytonk73

honkeytonk73 (http://cooking.videosift.com/member/honkeytonk73) — Wed, 23 Jul 2008 11:59:32 -0700

I don't believe in Gravity. It is just a 'theory' after all. I think we orbit the Sun because God tied an ethereal chain to the Earth and Sun. Forever linking the two bodies together.

Magic is real too.

By Lurch

Lurch (http://cooking.videosift.com/member/Lurch) — Wed, 23 Jul 2008 13:58:04 -0700

He should talk to this guy

http://www.videosift.com/video/Idiot-Judge-Says-Black-Hole-is-Racist

By dbalsdon

dbalsdon (http://cooking.videosift.com/member/dbalsdon) — Wed, 23 Jul 2008 14:24:10 -0700

"He should talk to this guy

http://www.videosift.com/video/Idiot-Judge-Says-Black-Hole-is-Racist "

Yeah. He has blogged about that story a few times IIRC.

By deathcow

deathcow (http://cooking.videosift.com/member/deathcow) — Wed, 23 Jul 2008 16:34:46 -0700

Gravity is such a weak force that the electromagnetic force in a tiny magnet can lift up a paperclip, far overwhelming the gravity from the Earths entire 6,600 _billion_ _billion_ _tons_ of mass.

By budzos

budzos (http://cooking.videosift.com/member/budzos) — Wed, 23 Jul 2008 18:29:53 -0700

It's a perfect explanation, gravity is a function of distance, object is smaller, therefore you can get closer, therefore gravity increases (exponentially).

Do you think that was explained clearly?

By sineral

sineral (http://cooking.videosift.com/member/sineral) — Wed, 23 Jul 2008 21:04:52 -0700

His explanation could be a bit better. The key to the answer to the viewer's question is that the universe doesn't recognize macro objects like stars, planets, etc; as far as gravity is concerned it's all just particles. He comes close to this when he talks about getting closer to the black hole because it's smaller, but he should have taken it a step further. If you were standing on the surface of a star, only some of the particles that make up that star would be close to you, most of them hundreds of thousands to millions of miles away from you. Since gravity's strength is dependent on distance, those far away particles would have relatively little effect on you. If you were standing on the surface of a black hole, those particles would all be only a couple miles at most away from you. That's ignoring the issue of what a black hole is really made of, which isn't relavent here; to be more accurate we could just replace of the concept of "x number of particles" with "x amount of mass".

That said, Phil Plait is good stuff. I check his blog daily.

By Payback

Payback (http://cooking.videosift.com/member/Payback) — Thu, 24 Jul 2008 17:52:36 -0700

>> ^deathcow:
Gravity is such a weak force that the electromagnetic force in a tiny magnet can lift up a paperclip, far overwhelming the gravity from the Earths entire 6,600 _billion_ _billion_ _tons_ of mass.

Actually... the magnet can do that only because its dinky.

By wax66

wax66 (http://cooking.videosift.com/member/wax66) — Fri, 25 Jul 2008 09:39:20 -0700

>> ^budzos:
Not a great explanation.

I concur. It's not just that you're getting 'closer to the object', he should specify that it's because every particle in that object, each containing its own gravity, is now closer to you. Saying that you just have to be closer makes it sound like if you were touching or at the center of the Sun, you'd get as much gravity as being right outside of a black hole of the same mass, which isn't the case. Someone of a technical mind may understand this without explanation, but unfortunately the average Joe/Jane probably wouldn't. To them, closer generally ends at touching, but sometimes include being inside the object. Either way it isn't good enough to just use the words 'closer to the object'.