Re: Speculation: Could this be an OSETI event?

Robert J. Bradbury (
Wed, 18 Aug 1999 18:39:12 -0700 (PDT)

On Wed, 18 Aug 1999, Larry Klaes wrote:
> Astronomers Baffled by Space Light
> ``It's fairly uncommon to stumble on something you don't
> have a clue about,'' astronomer S. George Djorgovski said
> Tuesday. ``It certainly hasn't happened to me, and I've
> been doing this for many years.''
> ...
> Some astronomers believe the object may be a new class of
> quasar, sources of energy found in the center of galaxies
> and believed to be powered by matter falling into massive
> black holes.
> ...

Djorgovski has a spectrum on his web site -- see links from: or

It shows a very noisy spectrum with two peaks at 580 and 620 nm. But the difference between the background and the peaks is less than an order of magnitude.

I think most OSETI people argue that the advantage of an OSETI signal is that it would outshine its star by many orders of magnitude. Though I will admit that most spectrometers have very long observation times and the OSETI people at least in some cases argue that the pulse widths would be very short. So if the pulses are averaged over the spectrometer exposure time, you could get the observed peaks. To know any more would require someone with device that can take nano- to microsecond exposures of the PSS 1537+1227 to determine if the bright peaks are being pulsed. I believe Horowitz's Optical SETI group at Harvard may be able to do this.

Robert Bradbury