Archivo de imágenes de Hubble
Cúmulo de galaxias Abell 520 (compuesto HST-CFHT-CXO)
This composite image shows the distribution of dark matter, galaxies, and hot gas in the core of the merging galaxy cluster Abell 520, formed from a violent collision of massive galaxy clusters.The natural-color image of the galaxies was taken with NASA's Hubble Space Telescope a...
- Fecha
- Jan 1, 2012
- Misión
- Hubble Space Telescope
- ID de archivo
- hubblesite-images-2012-10-2987-image
This composite image shows the distribution of dark matter, galaxies, and hot gas in the core of the merging galaxy cluster Abell 520, formed from a violent collision of massive galaxy clusters.
The natural-color image of the galaxies was taken with NASA's Hubble Space Telescope and with the Canada-France-Hawaii Telescope in Hawaii. Superimposed on the image are maps showing the concentration of starlight, hot gas, and dark matter. Starlight from galaxies, derived from observations by the Canada-France-Hawaii Telescope, is colored orange. The green-tinted regions show hot gas, as detected by NASA's Chandra X-ray Observatory. The gas is evidence that a collision took place. The blue-colored areas pinpoint the location of most of the mass in the cluster, which is dominated by dark matter. Dark matter is an invisible substance that makes up most of the universe's mass. The dark-matter map was derived from the Hubble Wide Field Planetary Camera 2 observations by detecting how light from distant objects is distorted by the cluster of galaxies, an effect called gravitational lensing.
The blend of blue and green in the center of the image reveals that a clump of dark matter resides near most of the hot gas, where very few galaxies are found. This finding confirms previous observations of a dark-matter core in the cluster. The result could present a challenge to basic theories of dark matter, which predict that galaxies should be anchored to dark matter, even during the shock of a collision.
Abell 520 resides 2.4 billion light-years away.
Credits
NASA, ESA, CFHT, CXO, M.J. Jee (University of California, Davis), and A. Mahdavi (San Francisco State University)Detalles de la imagen
| About The Object | |
|---|---|
| Object Name | Abell 520 |
| Object Description | Merging Galaxy Cluster |
| R.A. Position | 04h 54m 18.98s |
| Dec. Position | 02° 56' 48.8" |
| Constellation | Orion |
| Distance | 2.4 billion light-years (740 million parsecs) |
| About The Data | |
| Data Description | The image was created from Hubble data from proposal : J. Dalcanton (University of Washington, Seattle), A. Mahdavi (San Francisco State University), H. Hoekstra (Leiden Observatory), and A. Babul (University of Victoria, BC). The science paper is led by M.J. Jee (University of California, Davis). |
| Instrument | HST>WFPC2, CFHT, and Chandra |
| Exposure Dates | August 19-22, 2008, Exposure Time: 11 hours |
| Filters | CFHT (B), CFHT (V), HST/WFPC2 F814W (I), and CXO X-ray |
| About The Image | |
| Color Info | This image is a composite of separate exposures acquired by the HST/WFPC2 instrument, the Canada-France-Hawaii Telescope (CFHT), and the Chandra X-ray Observatory. Several filters were used to sample various wavelength and energy ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors are: White (visible): CFHT (B) + CFHT (V) + HST/WFPC2 F814W (I) Red (luminosity): CFHT Blue: HST/WFPC2 F814W (I) Green: CXO X-ray |
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La imagen y el material de referencia se acreditan al archivo oficial de la misión enlazado a continuación.
Ver en NASA.gov