The Missing Mass Mystery

For years, astronomers have been unable to find up to half of the baryonic matter in the universe. We may just have solved this problem.

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Dark Matter!

Dark Energy Playlist

We’ve known for some time that around 95% of the energy content of the universe is in dark matter and dark energy. This dark sector doesn’t interact with light in any way and so is invisible to us. The remaining 5% - the light sector – represents all of the regular matter in the universe. Yet what if I told you that all of the stars and galaxies and galaxy clusters only comprise 10% of the light sector. The rest has proved as elusive as the dark sector. We think it must exist as extremely diffuse gas in between the galaxies, yet our intense searches miss up to half of it. At least until now.

Resources
Graaff et al. 2017, "Missing Baryons in the Cosmic Web Revealed by the Sunyaev-Zel'dovich Effect"

Tanimura et al. 2017, "A Search for Warm/Hot Gas Filaments Between Pairs of SDSS Luminous Red Galaxies"

Written and Hosted by Matt O'Dowd
Produced by Rusty Ward
Graphics by Kurt Ross
Assistant Editing and Sound Design by Mike Petrow

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[papinkelman]

Possible evidence for string theory in 10000years. I can't wait.

No seriously I can't wait that long.

[Ed-quadF]

Don't know why, but I felt relieved when Matt said the epoch of star creation is just beginning.

[Master_Therion]

"Missing Mass Mystery." That's 3 letters M... "3M" is the company that makes Duct Tape. The universe is held together by Duct Tape confirmed.

[Pfhorrest]

I find it amazing and humbling to think about the distribution of energy from the top down instead of the bottom up.

So about 70% of the energy of the universe is of a form that hardly interacts with anything at all, uniformly distributed in a very diffuse way throughout the whole thing: dark energy.

About 25% is still in a form that hardly interacts with anything at all, but interacts with itself enough to clump together into a web of invisible filaments: dark matter.

About 2.25% is stuff that does actually interact in interesting ways but is just spread out diffusely through all of space not doing much interesting: the cold baryonic matter we'd already accounted for.

Another 2.25% of it is at least caught up in those invisible filaments and slowly flowing together: the lukewarm baryonic matter we just found.

About 0.4% is concentrated at the tiny points where those invisible filaments intersect, densely enough for some of it to start fusing and illuminating the rest of it incandescently. This tiny glowing fraction of a percent is ALL THE STARS IN THE SKY.

And only about 0.1% of all the energy in the universe is interacting stuff that has interacted enough to produce something other than a gas, but rather some specks of dust mostly floating around some of those stars, and just one of those innumerable specks of dust that altogether make up only that one tenth of one percent of energy in the universe is THE ENTIRE WORLD WE KNOW.

[mzterzi]

This series is a non-prescription pill for insomnia, thanks matt

[p]

It's oddly satisfying how Matthew always ends every video with "...space-time". Keep making more. GO PBS SPACE-TIME. <3

[maxsalmon]

Why is it so satisfying when he hits the final 'spacetime?' Dangit, brain, stop responding to patterns so instinctively!

[ossian]

You missed your opportunity. "It surrounds us and penetrates us; it binds the galaxy together."

[MaxStax]

Man has learned so much, it's mind boggling, yet so much we don't know.If this guy has kids, how lucky are they to get read a bedtime story in his voice.

[NewMessage]

Have you checked under my son's bed? Everything else in under there. Hear that, Timmy!?!? Clean your room! You're breaking the Universe!

[sebastianelytron]

*Q:* Where did the rest of the missing universe go?
*A:* It doesn't matter.

[maxchumka]

Wish I had youtube with this kind of channel when I was in school/college. Books are good but this presentation is beyond helpful.

[HB-jfyq]

*grabs popcorn, notebook, pen and turns on brain*

[flymypg]

A time-traveling monk from Middle Age England arrives in the current day. Being an ascetic, he's not impressed by our wealth and technology. He is, instead, delighted by the number of Christian churches to be found everywhere, generally multiple in a single town, some even situated next to each other! However, upon entering many of the churches, he is stunned and saddened by how few say a full Mass. This deeply perplexes the monk, whereupon he sets himself on a pilgrimage to solve...

The Missing Mass Mystery!

[roriemac]

Happy 1 Million subscribers. I don't know when you got so many but congrats.

[erik-ictp]

Dear PBS Space Time,

Is it possible to do a video about the possibility of a new big bang by quantum fluctuations?

Yours faithfully,

Erik de Wilde

[TehNoob]

Somebody call Jim Carrey, the mask is gone!

[Alazen.]

"The Missing Mask Mystery"
Notification squad knows what I'm talking about.

[kauske]

Q: What's another name for a metaphysical dinosaur?







A non-baryonic baryonyx

[ghostrider_gt]

I'm so early that even the title is wrong