
A selection of NASA Hubble Space Telescope snapshots of huge galaxy clusters that lie far away and far back in time. These are selected from a catalog of 92 new clusters uncovered during a six-year Hubble observing program known as the Medium Deep Survey.
If the distances and masses of the clusters are confirmed by ground based telescopes, the survey may hold clues to how galaxies quickly formed into massive large-scale structures after the big bang, and what that may mean for the eventual fate of the expanding universe.
The images are each a combination of two exposures in yellow and deep red taken with Hubble's Wide Field and Planetary Camera 2. Each cluster's distance is inferred from the reddening of the starlight, which is due to the expansion of space. Astronomers assume these clusters all formed early in the history of the universe.
HST133617-00529 (left) This collection of spiral and elliptical galaxies lies an estimated 4 to 6 billion light-years away. It is in the constellation of Virgo not far from the 3rd magnitude star Zeta Virginis. The brighter galaxies in this cluster have red magnitudes between 20 and 22 near the limit of the Palomar Sky Survey. The bright blue galaxy (upper left) is probably a foreground galaxy, and not a cluster member. The larger of the galaxies in the cluster are probably about the size of our Milky Way Galaxy. The diagonal line at lower right is an artificial satellite trail.
HST002013+28366 (upper right) This cluster of galaxies lies in the constellation of Andromeda a few degrees from the star Alpheratz in the northeast corner of the constellation Pegasus. It is at an estimated distance of 4 billion light-years, which means the light we are seeing from the cluster is as it appeared when the universe was roughly 2/3 of its present age.
HST035528+09435 (lower right) At an estimated distance of about 7 to 10 billion light-years (z=1), this is one of the farthest clusters in the Hubble sample. The cluster lies in the constellation of Taurus.
Credits
K. Ratnatunga, R. Griffiths (Carnegie Mellon University), and NASAAbout The Object | |
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Object Name | HST133617-00529, HST002013+28366, HST035528+09435 |
About The Object | |
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Object Name | A name or catalog number that astronomers use to identify an astronomical object. |
Object Description | The type of astronomical object. |
R.A. Position | Right ascension – analogous to longitude – is one component of an object's position. |
Dec. Position | Declination – analogous to latitude – is one component of an object's position. |
Constellation | One of 88 recognized regions of the celestial sphere in which the object appears. |
Distance | The physical distance from Earth to the astronomical object. Distances within our solar system are usually measured in Astronomical Units (AU). Distances between stars are usually measured in light-years. Interstellar distances can also be measured in parsecs. |
Dimensions | The physical size of the object or the apparent angle it subtends on the sky. |
About The Data | |
Data Description |
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Instrument | The science instrument used to produce the data. |
Exposure Dates | The date(s) that the telescope made its observations and the total exposure time. |
Filters | The camera filters that were used in the science observations. |
About The Image | |
Image Credit | The primary individuals and institutions responsible for the content. |
Publication Date | The date and time the release content became public. |
Color Info | A brief description of the methods used to convert telescope data into the color image being presented. |
Orientation | The rotation of the image on the sky with respect to the north pole of the celestial sphere. |