Planck’s Progress

Only time for a very quick post today, so I thought I’d just pass on some news I got via Chris North about how Planck is doing. As it happens, the satellite has recently reached  the point where it has observed about half the sky. It spins on its axis in rather stately fashion (at about one revolution per minute) and, as it moves in its orbit, that sweeps the telescope across the celestial sphere. Each scan is almost a great circle, but  these gradually creep around over about a six month period to cover the whole sky.

The nice picture below, in ecliptic coordinates, shows how far it has got. You can also see the Galactic plane, arching across the sky and showing up clearly at the frequencies Planck is sensitive to.

The Planck Consortium had an official meeting last week in Bologna at which they drank lots of wine and ate lots of food, but other than that nobody who was there has told me anything.

It’s all very hush hush don’t you know.