Until Sunday June 26 no Gamma-Ray Burst (GRB)
in the field of view of the Optical Monitoring
Camera (OMC) onboard INTEGRAL had been been observed.
This is not too surprising given the much smaller
field of view of the OMC compared to the gamma-ray
instruments.
However, an automated system is in place since launch,
which will make a triggered observation with the OMC
based on the coordinates which are provided by the on-ground
software IBAS (the INTEGRAL Burst Alert System).
Last Sunday a GRB triggered IBAS and an OMC observation
was started just 1m48s after the GRB brightened.
And here Murphy comes in to action....
Unfortunately this GRB occurred only a couple of
arc minutes away from one of the brightest stars
in the sky: Alpha Crucis; a magnitude 0.8 star.
The region where the GRB took place is severely
affected by saturation by this very bright star.
The chance of such an event occurring so close to such a
bright star (Alpha Crucis is the 13th brightest star in
the sky) is very small. And it tells us that also astronomers
have to face Murphy's law.
Hopefully the next GRB in the field of view of the OMC
will not be affected by an extremely bright star.
The figure shows the position of the GRB (red cross and green circle
representing the error circle) and the saturared image of Alpha Crucis.
