A Recent Big Bang
On March 30th an explosion that could be seen half-way across the Universe was witnessed here on Earth by a handful of telescopes around the world. Gamma
Ray Bursts are tremendous cataclysms of energy output from various astronomical processes. Many are the gigantic deaths of stars in far away galaxies. Others
might be generated by black holes swallowing enormous amounts of mass or perhaps the collisions of two neutron stars. Whatever the cause these explosions are
very bright. The first energies released come in the form of gamma ray photons. Shortly afterwords, when the materials of the exposions have cooled there is a
a short-lived optical afterglow. The game that astronomers play to detect these explosions is to get word (through e-mail) from a satellite in space that
is specifically designed to see these gamma ray bursts. The satellite (SWIFT-BAT) gives a rough coordinate position on the sky and the adroit observer
can swing his or her telescope to this piece of sky and find the afterglow.
This is exactly what I did on this March evening. My first image was taken just 20 minutes after the announcement of the GRB detection from the
SWIFT satellite. I continued to make measurements (300 second exposures) for the next 3 hours. The resulting light
curve of these observations is above. Please see the PRESS RELEASE
that announced these observations. Note that the light curve shown above indicates that as the afterglow faded,
it did not do so in a strictly smooth manner which hints that the explosion ran into other material during its
outward rush!
Clicking on the image above yields a Log-Log plot which shows a reasonably linear behavior as is expected with
these kinds of afterglows. You may also see a video of these observations by clicking
HERE
Exposure Duration: Luminance 3 hours
Unfiltered.
Celestron 11-inch SCT, SSBIG T1001 CCD camera
Credit: Adam Block/Seeing in the Dark Internet Telescope/Tim Ferris
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