Episode 18: Black holes

Find out what makes everybody's favorite deep-space oddity tick.

Questions, comments, or ideas for future episodes? Contact Liz and Bill at
cosmicadventures@astronomy.com

And be sure to check out more episodes of Cosmic Adventures!

Expand your knowledge at Astronomy.com
Intro to the Sky
Astronomy News
Videos

User Comments

Be the first to leave your comment below!

Only registered members of Astronomy.com are allowed to comment on this article. Registration is FREE and only takes a couple minutes.

Register Today!

NICOLAS TATARINOFF from AUSTRALIA (NSW) said:

If the accretion disk around a solar system forming sun is between 1 and 2 AU, what is the depth of the disk around a black hole?
What is the depth of a black hole?
If a black hole is spherical, wouldn't the accretion disk also be spherical?
When we are told of a jet of plasma being shot out of a black hole, how is this possible when we are told that nothing, not even light can escape?
Are the plasma jets produced by the extreme heat generated by the inner workings of the accretion disk?
So many questions, so little time.
Nicolas Tatarinoff, Sydney Australia

Submitted: 3/23/2013 10:25:42 PM (CST)

GRACE SOMMERS from NEW JERSEY said:

Awesome video! I love black holes.
Can you make a video about quasars?

Submitted: 12/7/2012 6:45:30 PM (CST)

TODD CHAMBERS from CALIFORNIA said:

What is the celestial purpose of a black hole? Is there any speculation on why they are at the centers of galaxies? Are there any emissions from black holes? Good video! Keep them coming!!

Submitted: 8/31/2012 2:31:27 PM (CST)

ANTHONY BARREIRO from CALIFORNIA said:

Nice backdrop. But I don't think Kara is quite massive enough to qualify as a black hole!

For us backyard observers, it's good to know that you can almost see a relatively close stellar mass black hole. More exactly, with even a small telescope you can see the ninth-magnitude massive O-class companion star of the stellar mass black hole Cygnus X-1, near the star Eta Cygni. The hardest part is deciding exactly which ninth magnitude star to look at. Astronomers figured out that this star, HDE 226868, must be in a binary system with a black hole because the system is emitting very powerful x-rays.

Submitted: 8/22/2012 1:57:43 PM (CST)