A NASA Hubble Space Telescope image of a previously unknown small group of galaxies estimated to be three billion light-years away. They existed when the universe was only about 80% its present age.
HST's high resolution reveals that many appear to be interacting and merging galaxies. In many cases, at least one member of each pair is blue in color, indicating active star formation, possibly triggered by interaction with a neighbor galaxy.
The observations promise to eventually lead to a much dearer understanding of galaxy evolution.
This image is part of a serendipitous sky survey which has been conducted over the past two years by Prof Richard Griffiths and colleagues at Johns Hopkins University, with a team of astronomers in the U.S. and Britain.
The survey is one of several Key Projects for Hubble. In previous images, the deep survey has uncovered a bizarre variety of shapes and structures in distant galaxies, which only previously appeared as fuzzy blobs from ground based telescopes.
Technical Description
The left-hand frame is a composite "true-color' image taken by Prof Rogier Windhorst and colleagues of Arizona State University, using the 90-inch telescope at Steward Observatory, University of Arizona. The right-hand frame is a "true-color" composite of 9 images taken in visible and near infrared light with the Wide Field Camera, in May 1993. Each exposure was about 30 minutes long. The field of view is 44 arc seconds across, corresponding to a span of 600 thousand light-years at the measured distance to the brightest galaxy in the image. The resolution is 0.1 arc seconds, about 10 times better than can be routinely achieved from the ground.
Credits
Richard Griffiths, The Johns Hopkins University and NASA| About The Object | |
|---|---|
| Object Name | NGC 5548 |
| R.A. Position | 14h 17m 59.65s |
| Dec. Position | 25° 8' 13.4" |
| About The Object | |
|---|---|
| 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 |
|
| 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. |
