Universe 

Dark Flow

Distant galaxy clusters mysteriously stream at a million miles per hour along a path roughly centered on the southern constellations Centaurus and Hydra. A new study led by Alexander Kashlinsky at NASA's Goddard Space Flight Center in Greenbelt, Md., tracks this collective motion — dubbed the "dark flow" — to twice the distance originally reported, out to more than 2.5 billion light-years.

The study used a new technique to determine the motion of X-ray-emitting galaxy clusters. The clusters appear to be moving along a line extending from our solar system toward Centaurus/Hydra, but the direction of this motion is less certain. Evidence indicates that the clusters are headed outward along this path, away from Earth, but the team cannot yet rule out the opposite flow.

The video shows the team's catalog of galaxy clusters separated into four "slices" representing different distance ranges. A colored ellipse shows the flow axis for the clusters within each slice. While the size and exact position of the ellipses vary, the overall trends show remarkable agreement. The video includes images of representative clusters in each distance slice.

The dark flow is controversial because the distribution of matter in the observed universe cannot account for it. Its existence suggests that some structure beyond the visible universe — outside our "horizon" — is pulling on matter in our vicinity.


For More Information

http://www.nasa.gov/centers/goddard/news/releases/2010/10-023.html


Credits

Scott Wiessinger (UMBC): Lead Animator
Scott Wiessinger (UMBC): Producer
Francis Reddy (SPSYS): Writer
Please give credit for this page to NASA/Goddard Space Flight Center. However, each image should be credited as indicated above.

Short URL to share this page:
http://svs.gsfc.nasa.gov/goto?10580

Data Used:
WMAP None

This item is part of these series:
Astrophysics Visualizations
Astrophysics Stills
Astrophysics Features

Goddard TV Tape:
G2010-139 -- Various Small Astrophysics projects

Keywords:
SVS >> Galaxy
SVS >> HDTV
DLESE >> Space science
SVS >> Astrophysics
SVS >> WMAP
SVS >> Universe
SVS >> Dark Flow
SVS >> Galaxy Cluster
NASA Science >> Universe