NASA Podcasts

NASA Mission Update: SWIFT
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They occur approximately once per day; brief, intense, powerful explosions of gamma ray radiation of the likes not seen since the Big Bang. They are called Gamma-ray bursts and, scientists are somewhat mystified as to their cause. Do they signal the birth of a black hole in a massive stellar explosion? Are they the product of two colliding neutron stars, or is there something else that prompts this intriguing phenomenon?

With its launch into low-Earth orbit in November 2004, scientists have a dedicated tool with which to probe the gamma-ray burst mystery.

Ilana Harrus, Program Scientist: "Before SWIFT launched, to give you an example, the satellite that actually saw the long burst, it took them eight hours to go and look at that burst; Swift can do this in less than a minute.."

Named after the bird able to quickly snatch insects as it flies, the Swift observatory is agile, quickly pointing its instruments at gamma-ray bursts and relaying burst locations to the ground within seconds.

Ilana Harrus, Program Scientist: "Swift can see usually, on average, a hundred bursts per year. The number of bursts that actually exists in the universe, that we think are actually happening in the universe is, of course, much higher. We think we actually see like one in one thousand."

This quick response is achieved by a complement of three onboard instruments. The largest instrument, the Burst Alert Telescope or BAT, can view approximately a sixth of the entire sky at one time; the X-ray, and the Ultraviolet/Optical Telescopes enable high-precision X-ray and optical positions and spectra to be determined. Swift burst alerts allow both space-based and ground-based telescopes around the world to observe a burst's afterglow immediately after its detection.

Ilana Harrus, Program Scientist: "Swift doesn’t just look at gamma-ray bursts and that's all they do, they study a very large array of science which has come as an added bonus really to the mission. For example, they detected the first x-ray flash coming from a star that was just about to explode."

An international effort, Swift has observed some 450 bursts since its launch and provided the most comprehensive study of Gamma Ray Burst afterglows to date.

Ilana Harrus, Program Scientist: "Swift is really providing us with a list of discoveries that just keep on growing, and for a satellite, or for a mission that size, which had, initially, had a very focused goal which was gamma-ray bursts, this is the gift that keeps on giving."

For more information on the Swift Mission log on to:

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