This is a false-color Hubble Space Telescope image of the visible fireball which accompanied the gamma ray burst called GRB 970228. This is the first optical image ever taken which associates a gamma-ray burst source with a potential host galaxy. This observation provides strong supporting evidence that gamma-ray bursts are cosmological- they originate in distant galaxies across the universe.
The burst was detected on February 28, 1997. The Hubble picture is a combination of two images taken on March 26 and April 7, with the Wide Field Planetary Camera 2 (in planetary camera mode).
The arrow points to the fireball, which is a white blob immediately to the upper left of image center. Immediately to the lower right of center is an extended object (roughly resembling an "E") interpreted to be the host galaxy where the gamma-ray burst is embedded. A follow-up image taken on April 7 showed the fireball had faded, but not the extended source, supporting the interpretation it is a host galaxy at great distance.
It may be a significant finding that the fireball is offset from the center of the galaxy. This rules out a supermassive black hole that could be at the galaxy's core, as the source of the gamma-ray burst. A more likely explanation is that the burst came from the titanic collision of two neutron stars, or a neutron star with a stellar-mass black hole, in the disk of the galaxy.
Credits
K. Sahu, M. Livio, L. Petro, D. Macchetto, STScI and NASA| About The Object | |
|---|---|
| Object Name | GRB 970228 |
| R.A. Position | 05h 1m 57.0s |
| Dec. Position | 11° 46' 23.99" |
| 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. |
