Re:GRBs

John D. Gleason (gleasojb@bc.edu)
Sat, 3 May 1997 12:29:11 -0400 (EDT)


In a message dated 5/2/97 12:24:27 AM, John Clark wrote:

>The Hubble telescope was quickly turned to the spot and at the
>very limits of its sensitivity found a extremely faint optical dot in a
>Galaxy several billion light years away, 2 days later the dot was gone.
>It's incredible, this sucker was big, for the Gamma rays to be as bright as
>they were this far away, it must have been HUGE. I wouldn't want to be in
>the same Galaxy with a Gamma ray source of that intensity, even if it only
>lasted a minute.

According to a news story in the April 25 Science [276:529-530] there is
now some debate as to the source of the GRBs. The initial analysis of the
Hubble data 26 and 38 days after the burst confirmed the reported fading
point source. However, Caraveo, et al of the IFC in Milan analyzed the
data separately using what they claim to be "superior software" and
concluded that the apparent source was moving across the sky. Based on
their analysis, the object may be only a few hundred lightyears away,
closer than even the galactic source proponents had previously imagined.
They could be seeing "anything from a transient cloud of gas associated
with the burst to a background galaxy, aligned by chance with the
pointlike object." Astronomers hope to resolve this in a few months when
the point source emerges from behind the glow of the sun - if it's still
visible.

In a related story, the recent claim of a cosmic axis by researchers at
Rochester and Kansas has been met with considerable skepticism. They
supposedly used old data, ignoring 99% of recent radio galaxy observations
and their conclusions are based on an outdated theory of radio wave
polarization. The two researchers are still confident that future
studies will support their theory.

John <gleasojb@bc.edu>