October 17th, 2011 at 2:10PM
(via APOD: 2011 October 17 - MACS 1206: A Galaxy Cluster Gravitational Lens) MACS 1206 is the one that Phil showed us earlier on Bad Astronomy, but I love this detail shot so much that I’m posting it again from APOD. The lensing effect that the cluster is having on the background galaxies allows us to determine how much dark matter is in the cluster and how it is distributed. It requires a certain amount of gravity to make the light from a background galaxy warp and lens a certain way, and by comparing the lensing to the the amount of visible mass in the image, scientists can calculate the dark matter distribution. Image Credit: NASA, ESA, M. Postman (STScI), and the CLASH Team

(via APOD: 2011 October 17 - MACS 1206: A Galaxy Cluster Gravitational Lens)

MACS 1206 is the one that Phil showed us earlier on Bad Astronomy, but I love this detail shot so much that I’m posting it again from APOD. The lensing effect that the cluster is having on the background galaxies allows us to determine how much dark matter is in the cluster and how it is distributed. It requires a certain amount of gravity to make the light from a background galaxy warp and lens a certain way, and by comparing the lensing to the the amount of visible mass in the image, scientists can calculate the dark matter distribution.

Image Credit: NASA, ESA, M. Postman (STScI), and the CLASH Team

34 notes Source: apod.nasa.gov #APOD#NASA#CLASH#sky survey#HST#Hubble#Hubble Space Telescope#gravitational lensing#galaxy cluster#cluster#galaxy#dark matter#astronomy#astrophysics#science#physics#optics
October 14th, 2011 at 5:18PM
(via Galaxies swarm and light bends under dark matter’s sway | Bad Astronomy | Discover Magazine) Holy mother…4.5 billion light years away from us is a galaxy cluster (MACS J1206) with a mass 1 quadrillion times the mass of the Sun. And it’s bending light. It’s bending light more than it should based on what we can see. Conclusion? Dark matter. You can tell how much and where it is based on how the galaxies behind the cluster are bent and smeared. It’s called gravitational lensing and it’s really nifty looking. Phil’s got a great write-up, and this is a Hubble shot from the CLASH project, which is getting an unprecedented 524 orbits with Hubble. That’s 300 hours of continuous viewing. The Hubble data will also be used by this team to point the ESO’s VLT telescope in Chile at various targets to get spectrometry readings. Interesting structures Phil would like to point out to you in the shot: Galaxy being lensed by the cluster and, it would appear, also by the other two galaxies that you can see. Very red galaxies which may be very small members of the same cluster (dust in the way) or very old (red-shifted). Image credit: Credit: NASA, ESA, M. Postman (STScI) and the CLASH Survey Team

(via Galaxies swarm and light bends under dark matter’s sway | Bad Astronomy | Discover Magazine)

Holy mother…4.5 billion light years away from us is a galaxy cluster (MACS J1206) with a mass 1 quadrillion times the mass of the Sun. And it’s bending light. It’s bending light more than it should based on what we can see. Conclusion? Dark matter. You can tell how much and where it is based on how the galaxies behind the cluster are bent and smeared. It’s called gravitational lensing and it’s really nifty looking.

Phil’s got a great write-up, and this is a Hubble shot from the CLASH project, which is getting an unprecedented 524 orbits with Hubble. That’s 300 hours of continuous viewing. The Hubble data will also be used by this team to point the ESO’s VLT telescope in Chile at various targets to get spectrometry readings.

Interesting structures Phil would like to point out to you in the shot:

Galaxy being lensed by the cluster and, it would appear, also by the other two galaxies that you can see.

Very red galaxies which may be very small members of the same cluster (dust in the way) or very old (red-shifted).

Image credit: Credit: NASA, ESA, M. Postman (STScI) and the CLASH Survey Team

25 notes Source: blogs.discovermagazine.com #bad astronomy#astronomy#CLASH#Hubble#HST#gravitational lensing#astrophysics#dark matter#VLT#Very Large Telescope#spectrometry#space#galaxies#galactic cluster#MACS J1206#red-shift