In article ,
Moderate Mammal writes:
What is more, if telescopes are observing a signal that is drifting in
frequency, then each time they look for it they should most likely
encounter it at a slightly different frequency. But in the case of
SHGb02+14a, every observation has first been made at 1420 megahertz,
before it starts drifting.

Would one of the radio experts care to comment on this? To me, it
suggests some artifact of the Arecibo receiving system, probably in
conjunction with some RFI source on the ground or a sidelobe of some
bright radio source. I confess, though, I don't see how feed horn
position could translate into a frequency shift, but I'm no expert.

--
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA
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