spacetoday.net: Powerful gamma-ray burst was aimed at Earth

Posted: Fri, Sep 12, 2008, 7:31 AM ET (1131 GMT)
GRB 080319B illustration (NASA/Swift/Mary Pat Hrybyk-Keith and John Jones)

A powerful gamma-ray burst detected earlier this year that created an afterglow briefly visible to the naked eye was aimed almost directly towards the Earth, scientists said this week. The burst, GRB 080319B, took place on March 19th and was detected by NASA's Swift spacecraft and several other satellites, and produced an optical afterglow that reached magnitude 5.3, despite being 7.5 billion light-years away. Scientists analyzing space- and ground-based observations found that the bursts's brightness came from a central narrow jet consisting of material traveling at 99.99995 percent the speed of light, aimed almost directly towards the Earth. Astronomers said they normally only see a wider, somewhat less energetic jet from such bursts, and don't know if all GRBs have a such a narrow, intense central jet.