Archive for the ‘Planck’ Category

The waiting is almost over…

January 6, 2011

All of us on Planck have got used to bring tight lipped about the results we’re getting. Next week, some of the security will relax as Planck will release it’s first data products and first scientific results.

The bad news is that there will be no cosmology in this release – all the science relates to ‘foreground’ objects.

The good news is that the objects that are in the ‘foreground’ as far as the CMB is concerned is everything else in the universe, so there’s a lot to talk about.

Planck will also be releasing it’s first source catalogs so there will not only be new results on a wide variety of topics, but there will also be data for non-Planck astronomers to work on.

So next week is a big week for Planck!

Planck moving forward

July 6, 2010

It’s rather ironic that the massively successful press release of the Planck all-sky maps came out yesterday when many Planck scientists were in Paris at the ‘Core Team’ meeting. I would have been there myself, and would have missed the chance of appearing on the BBC, if I hadn’t had to be at Imperial for an examiners’ meeting.

Now I’m at the core team meeting, seeing the latest work on Planck. There’s a lot of work being done and a lot of good things coming. Yesterday’s images are just a start, but we have a huge amount of work to do before things are finished.

New Results: First All Sky Images from Planck!

July 5, 2010

ESA today released the first all sky images from Planck. The first all sky survey was completed a few months ago, but it’s taken some time to get things processed to the stage where we can release images. So here it is – Planck’s first view of the whole sky!

The image is dominated by the dust in our own galaxy, seen in blue, but in the top left and bottom right you can see a more mottled structure which is the cosmic microwave background. The next all sky survey, currently being observed, and a lot of processing are needed to remove the foreground galactic emission and the emission of intervening galaxies and galaxy clusters before we can get a clear picture of the microwave background. That’s the point at which we will be able to see the exciting new results on cosmology that will come from Planck.

There’s a lot more to come as well, as this image shows, with information on our own galaxy and others. This overlay shows some more information about what we’re seeing and highlights well known objects and parts of the sky, as well as images already released from Planck.

More coverage available from ESA and the BBC.

Planck images of our Galaxy

March 17, 2010

A new press release from the European Space Agency presents some of the first new science from the planck satellite. We don’t have results from the microwave background yet – we need another 6 months to complete the second all sky survey and then a lot of time for data crunching for that – but what the new results show are exquisite images of cold dust in our own galaxy in what is the largest area submm survey so far made.

What can be seen here is the galactic plane itself – the line running horizontally across the image near the bottom – and the huge clouds of cool dust that rise far above the plane. Hints of these were first seen by the IRAS satellite, but the Planck observations are at much longer wavelengths and are thus able to find cooler dust and determine dust temperatures.

These results also highlight the synergy between Planck, which gives us the largest scale structures in the galactic dust, Herschel, which can show us smaller scale structures (see eg. here), and ground-based telescopes such as the JCMT which can work at still higher resolutions.

This is all just a taster of what Planck will produce, but there’s lots more work to be done, and observations to be made, before we get there.

Planck Completes First Survey of the Sky

February 28, 2010

On February 14th, Planck completed its first survey of the whole sky. But there was no rest – it immediately started on its second all-sky survey.

The nominal Planck mission is for two all sky surveys, with the second survey completed in 6 months from now. However, the satellite is using cryogens sufficiently sparingly that it’s capable of two further all sky surveys, for a total of 4. This will give it greater sensitivity, greater control of systematic effects, and a chance to extend its search for variable and moving, ie. solar system, objects. ESA has approved this extension, so the project will certainly go to 4 surveys. Quite what STFC, the UK astronomy funding body which is going through a series of financial crises, will do about this isn’t clear…

New Year, New Science

January 7, 2010

Planck is the top item in Nature‘s look at key events that may come from reserahc in 2010:

‘Planck peaks at the Universe’s Origin… Planck… could alter theories about the origin and structure of the early universe’.

I’m not sure we’ll be releasing too many results in 2010, but it’s good to see the scientific potential of Planck recognized in Nature‘s list!

Planck sees the Crab

September 29, 2009

[cross-posted from Planck UK site]

Last week, the Planck satellite observed the Crab Nebula, also known as M1 from Messier’s catalogue, and Tau A to radio astronomers. The Crab Nebula is one of the brightest objects in the sky at radio and sub-mm wavelengths, and is used by many astronomers to calibrate their instruments. It is the remnants of a star which underwent a violent and catastrophic explosion at the end of its life, an event known as a supernova. The Crab Nebula is associated with one of the few supernovae which was observed, as it was seen by Chinese and Arab astronomers in 1054.

Hubble image of the Crab Nabula
Hubble Space Telescope image of the Crab Nebula, showing the colourful nebula and filaments. Image credit: NASA/ESA

After the supernova, the outer layers of the star were scattered widely into a huge cloud of gas, which we now see as a nebula, and is frequently observed by amateur and professional astronomers. The core of the star ended up as a pulsar, a rapidly rotating, magnetised neutron star. However, it is the surrounding nebula that Planck is interested in. The nebula is around 13 lightyears across, which is around 10,000 times larger than our solar system (depending on where you define the edge). It is also relatively close in astonomical terms, at about 6 lightyears distance, and so is also relatively large in terms of astronomical objects see from Earth. It is around 7 arcminutes across, which is 7/60th of a degree, or about 1/4 the diameter of the full moon as seen from Earth. The smallest of Planck’s beams on the sky is 5 arcminutes and the largest 30 arcminutes, so to the majority of Planck’s detectors the Crab Nebula will have appeared as a “point source” – a single blip in the data. However, it is so bright that it would still be very obvious.

SCUBA measurements of the Crab nebula
SCUBA image of the Crab Nebula at 350GHz. The colour shows the brightness (blue/black=dark, red/white=bright), and the length og the black lines shows the relative amount of polarisation. Image credit: J.S. Greaves, W.S. Holland & T. Jenness (Joint Astronomy Centre)

Because the central pulsar is magnetised, the Crab Nebula is permeated by a magnetic field. This causes any electrons in the nebula, of which there are many, to spiral around the magnetic field lines and emit radiation known as synchrotron radiation. This radiation, which is brightest at radio wavelengths, but still very strong at Planck frequencies, is polarised, which makes the Crab an ideal object for calibrating the polarisation-sensitive detectors on Planck. Many experiments have observed its polarised radiation, including the SCUBA instrument on the JCMT on Hawaii, which observed it at 350GHz (a wavelength of 850 microns). One of the properties of synchrotron radiation is that it varies in a fairly predictable way with frequency, so it is possible to tell from an observation at one frequency what it will look like at another.

The data will take time to analyse, but will be ingested into the Planck database and used to help calibrate its instruments. The Crab Nebula is not the only calibration source, but is the best single source in the sky for calibrating the polarisation angles.  Other non-polarised sources include the planets in our own solar system, particularly Jupiter, which are very bright at Planck’s frequencies as well as to the naked eye.

In the News

September 18, 2009

Various news outlets have picked up on the Planck press release. These include:

The Telegraph who even quote me!

The Times

AFP via Google



And I’m sure there will be more. Anybody who spots something please add to the list via a comment!

First Results from Planck Released!

September 17, 2009

ESA has just announced the first results form the Planck satellite. The ESA release can be found here and some more images and information (if you can read French) can be found here, and similar extra details are also on the UK Planck site here. My colleague Andrew Jaffe also has his take on things here.

These first images of strips of the sky look great, and are visibly better than those from WMAP, the previous NASA CMB satellite. We have a lot more work to do to cover the entire sky. Only then can we start to look at the details of the microwave background and the Big Bang physics that this allows us to probe. But this is a great start to things!

The Planck First Light Survey

Press Release Imminent!

September 17, 2009

There should be a Planck press release later today, showing images from the first look survey.

Watch this space for more news and links to the images once ESA has released them. All I can say for the moment is that things are looking good!