I went to one of our so-called 'CTP' meetings last week in Cambridge. I don't get to many. 'CTP' is an odd acronym -- the 'C' is the symbol we use for sky power spectra, ant eht 'T' and the 'P' stand for 'temperature' and 'polarization'.

Since the meetings are supposed to be work sessions, we all bring our computers and try to act antisocial:



A couple of colleagues kept asking what sort of bizarre meeting this was, since whenever they went by the room, nobody seemed to be talking.

I only got to sneak away once, to see the Wipple Museum of the History of science. But they've got a telescope made by Herschel, after whom our sister satellite is named:

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and I did get a picture of the "Mathematical Bridge":
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I always wonder why the French and the English pretend to hate each other so much:
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We just found out today that one of the leaders of the Planck project, Andrew Lange, died yesterday.



He was one of the most respected people not only on the Planck project, but also in the CMB field, cosmology and physics in general. He led the development of some of the most important technical advances in the field, and used these advances to make some the most important cosmological measurements ever. His teams have made measurements of such mind-boggling things as the geometry of the Universe and the energy content of the Universe. He led the design and creation of the heart of the Planck/HFI instrument. His suicide is a staggering shock and a tragic loss for all of us who knew him.

The Planck data is telemetered down for a period of about three hours each day. During this time there are always at least two people on duty in the somewhat misleadingly named "HFI Operation Center".

The center is located in Orsay Ville, a southern suburb of Paris



It's about an hour's ride on the suburban metro here -- not far, but those of us who live in the center grumble sometimes about having to go "all the way to Orsay" anyway. Never mind that it's still far easier for us than for the people living in other cities and countries, who are nevertheless supposed to put in some operations duty as well (though those in Paris do more).

The Center is housed in the Space Astrophysics Institute on the South campus of the University of Paris:



The center itself is really just one room with a bunch of computer terminals, where we can display much of the information coming down during the download period. Here is a picture of the room with Karin and Maryse:



It was exciting coming here the first couple of times, but now it's really just a chore. We come in about a half hour before the data starts flowing. As soon as the download starts, we check that data is flowing and that some of the basic temperatures and pressures are within nominal range. We process some of the data downloaded from the day before and check some of these to make sure there haven't been any strange events.

Most of the data we get was actually taken during the preceding day, stored onboard, and only downloaded to us at this time. But we do get some "near real time" data that we also check, to get an idea of how the instrument is doing at that moment. The whole session is about three-and-a-half hours, but I have to admit that a large fraction of that is spent surfing the web, once we're sure the instrument is behaving nominally. We do, however, stay during the entire period -- you'd feel really stupid if something went wrong while you were there and you didn't notice or do anything about it!

Part of the ESA Planck team is based at the European Space Astronomy Center outside of Madrid. Last Monday they hosted a meeting to work on the preparations for distributing the Planck data, when the time comes.

It's a bit out of the way, and sort of a pain to get to, but is a pretty unique setting.



The ruins of the 15th century castle give the area its name: Villafranca del Castillo.

The picture above shows a bunch of the Planck team milling around on the street outside a restaurant in Bologna, where we ultimately had out "social dinner" yesterday.

This is the first time the entire team has met since data has started coming down, so people were excited. There are some things that will require a lot of work, but the basic feeling seemed to be something along the lines of "Wow, I never believed it would work this well."

One hiccup so far has been that some people seem to have been "pushing" our "communication policy" to its limits. We are not supposed to show the data outside of the consortium until it has been thoroughly processed and validated. The project scientist showed this viewgraph to try to make the policy clear:


So, since we can't talk about the Planck data yet, all I can do is show you the little trinkets we got at the meeting. It seems the Netherlands (where there is a big European Space Agency installation) has actually issued stamps with Planck and Herschel on them:


Planck is the most sensitive CMB satellite ever launched, but more important than that, since there are scientists from all over Europe working on it, it's also a fabulous way to exchange commemorative euro coins, if you do this sort of thing (-:
(these are from Anne from Finland).

I had time for only one mildly touristy visit, to the Asinelli Tower in the center of Bologna: