Deep Time: Crash Course Astronomy #45

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As we approach the end of Crash Course Astronomy, it’s time now to acknowledge that our Universe’s days are numbered. Stars will die out after a few trillion years, protons will decay and matter will dissolve after a thousand trillion trillion trillion years, black holes will evaporate after 10^92 years, and then all will be dark. But there is still hope that a new Universe will be born from it.

Crash Course Astronomy Poster:

Hawking Radiation Mechanism resources:

Table of Contents
The Universe’s Days Are Numbered 0:32
Stars Eventually Die Out 3:02
Protons Eventually Decay 5:04
Bye-Bye Black Holes After 10^92 Years 7:49
With Death Comes Life 12:04

PBS Digital Studios:

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Hubble ACS SWEEPS Field [credit: NASA, ESA, W. Clarkson (Indiana University and UCLA), and K. Sahu (STScI)]
Flare [credit: NASA’s Goddard Space Flight Center/S. Wiessinger]
Hubble Views Stellar Genesis in the Southern Pinwheel [credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)]
White Dwarf [credit: NASA, ESA, H. Bond (STScI) and M. Barstow (University of Leicester)]
Neutron Star Illustrated [credit: NASA, Casey Reed – Penn State University]
Black Holes: Monsters in Space [credit: NASA/JPL-Caltech]
Binary Neutron Star Video [credit: NASA]
Giant Elliptical Galaxy NGC 1316 in Fornax Cluster [credit: ESO]
Proton Aurora [credit: NASA/Goddard Space Flight Center Conceptual Image Lab]
A Race Round a Black Hole [credit: NASA/Dana Berry, SkyWorks Digital]
The Big Bang [credit: NASA]
Hubble Ultra Deep Field 2014 [credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)]
Galaxy [credit: Subaru Telescope (NAOJ), Hubble Space Telescope, Robert Gendler]
One star, many stars (M13) [credit: Rogelio Bernal Andreo]
Earth [credit: NASA’s Earth Observatory]
Explosion video [credit: Shutterstock / Richard Finch]


Der Nesor says:

So the cosmic reboot expands at the speed of light … but which one ? Our old one , the maybe new speed of light, maybe there is no speedlimit in the new universe…. Two physics actually literally colliding , how could you not love science!

Brandon Bickaroo says:


Cristian Garcia says:

This was the most interesting/saddest video ever. Mix feeling now =?

Peder Hansen says:

how can they confidently state the universe is 14 billion years..when we don`t see the edge of this universe. yes..i know about wmap, planck and the background radiation. but they are basing this theory upon layers of other theories that all can be wrong. don`t be surprised if this changes with a big number a few years from now. I would respect these scientists a lot more if they didn`t produce these things as facts. because they clearly aren`t

Veronika Alcoba says:

The thought of Crash Course Astronomy ending soon makes me sick.

muffinluveruuu says:

On to Crash Course Pornography!

Trans4mers84561 says:

Time is a tool you can put on a wall, or wear it on your wrist.
The past is far behind us, the future doesn't exist.

mozilla82 says:

I feel small. Really small.

Robin Hice says:

I've had the thought before that our expansions and colapses might be like heartbeats. As if our entire universe is a cell in the heart of what some would call God.

Joe Masters says:

Just mind blowing.

Nordivision says:

If time is just evolution of entropy, shouldn't time kind of stop when the last particle decays and the complete equilibrium stage begins

rediius says:

I love how in the middle of a very technical explanation he refers to the "doobly do" in the description.

rediius says:

I love how in the middle of a very technical explanation he refers to the "doobly do" in the description.

mavog77 says:

Please don't end this Crashcourse-Series before we have at least reached the end of the Stelliferous Era! That would be great, thanks!

jbhballe520 says:

How can there be more universes if the our universe is infinite and expanding into nothing? Is that not true? Also what about singularities?

Kristoff says:

A universe whose fires and warmth are going out, slowly being replaced by inevitable cold, darkness… Dark Souls, anyone?

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