NOVA: The Dark Matter Mystery

We can't see dark matter, and some skeptics doubt its existence, but many scientists think it makes up 20-some percent of our universe. Astronomer Doug Clowe explains how the Bullet Cluster, a group of galaxies billions of light years away, may shed some light on this mysterious stuff.

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Video podcast produced by Melissa Salpietra and Susan K. Lewis. Edited and narrated by Melissa Salpietra. Original footage and interviews produced by Julia Cort. NOVA is produced by WGBH in Boston. Funding for NOVA scienceNOW is provided by Pfizer, the National Science Foundation, the Howard Hughes Medical Institute, the Alfred P. Sloan Foundation, the Corporation for Public Broadcasting, and public television viewers.

This material is based upon work supported by the National Science Foundation under Grant No. 0407101. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Category:

Science & Technology

Tags:

• science
• NOVA
• PBS
• dark
• matter
• Doug
• Clowe
• Bullet
• Cluster
• galaxy
• astronomy
• astrophysics
• cosmic

[thetruthis9]

they uploaded this video twice...

[tonypata]

So, Nova has basicaly become a children's show. Remember Zoom and The Electric Company.

[eziekiel9989]

the gravity is drawn to the galaxies because of the black whole in the center of all galaxies...

'3: 45 there is clearly some stuff there that is not normal matter and is making alot of gravity'

black wholes: points of infinity

dark matter is the singularity at the center of being

[StudioSCAPE]

Its LHC (Large Hadron Collider.)

[GetMeThere1]

I don't know....sounds racist to me ;)

[Utka9]

Interesting...what about the LCH?

[starlette92]

(Part 5)

I hope what i've written here helps somewhat in understanding the study of dark matter, or at the very least, why dark matter isn't "just" a theory

[starlette92]

(Part 4)

the studies show the dark matter is likely distributed in some sort of halo, dispersed all around the galaxy, but especially "dense" in the outer regions of the galaxy.

dark matter isn't a miscalculation at all. there is a lot of evidence supporting it, and theoretical models which use dark matter in that halo configuration mentioned above, are MUCH better at replicating real galaxy behaviour than models without.

for further information, check out undergraduate astronomy texts.

[starlette92]

(Part 3)

possible candidates are lone black holes (not accreting matter or in a binary system, where it could easily be detected), neutrinos, lone brown dwarfs (no-fusing, Jupiter-type bodies), among other things.

you may also think that matter that gets swallowed in a black hole might be a candidate, but the black hole grows in size after swallowing the matter, so its mass isn't "lost"

also, studies of the motion in galaxies tells us that the dark matter isn't clumped at the center

[starlette92]

(Part 2)

i.e., stars + gas + dust + black hole(s) + planets + etc... is much less than what is responsible for the motions. it is not implausible that there is some form of matter which does not radiate in observable bands and which is not near other visible bodies such that we could measure its gravitational influence over those bodies. in essence, dark matter is dark since we can't "see" it in any (current) way other than its inferred gravitational influence.