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The first scientific results from ESA’s Planck mission were released at a press briefing in Paris on the 11th January 2011 - the full press briefing can be viewed online on the ESA website. The findings focus on the coldest objects in the Universe, from within our Galaxy to the distant reaches of space.

Following the publication by ESA of the first full-sky Planck image in July last year, we can now see the release of the first scientific results from the mission. The basis of many of these results is the Planck mission’s ‘Early Release Compact Source Catalogue’. Drawn from Planck’s continuing survey of the entire sky at millimetre and submillimetre wavelengths, the catalogue contains thousands of very cold, individual sources which the scientific community is now free to explore.

“This is a great moment for Planck. Until now, everything has been about collecting data and showing off their potential. Now, at last, we can begin the discoveries,” says Jan Tauber, ESA Project Scientist for Planck.

Visible-light telescopes see little more than the tapestry of galaxies around us. But by making measurements at wavelengths between the infrared and radio, Planck is able to work back in time and show us much more. The results released contain important new information about the stage when the galaxies were being assembled.

Planck has found evidence for an otherwise invisible population of galaxies shrouded in dust billions of years in the past, which formed stars at rates some 10–1000 times higher than we see in our own Galaxy today. Measurements of this population had never been made at these wavelengths before. “This is a first step, we are just learning how to work with these data and extract the most information,” says Jean-Loup Puget, CNRS-Université Paris Sud, Orsay, France.

Eventually, Planck will show us the best views yet of the Universe’s first act: the formation of the first large-scale structures in the Universe, where the galaxies were later born. These structures are traced by the cosmic microwave background radiation, released just 380 000 years after the Big Bang, as the Universe was cooling.

Further findings included the discovery of the cause of contaminating emission from foreground sources which has obscured previous Planck images; Data collected across Planck’s unprecedented wide wavelength range confirm the theory that it is coming from dust grains set spinning at several tens of billion times a second by collisions with either fast-moving atoms or packets of ultraviolet light.

This new understanding helps to remove this local microwave ‘fog’ from the Planck data with greater precision, leaving the cosmic microwave background untouched.

Among the many other results presented, Planck has also shown new details of distant clusters of galaxies. These show up in the Planck data as compact silhouettes against the cosmic microwave background. The Planck Collaboration has identified 189 so far, including 20 previously unknown clusters that are being confirmed by ESA’s XMM-Newton X-ray observatory.

By surveying the whole sky, Planck stands the best chance of finding the most massive examples of these clusters. They are rare and their number is a sensitive probe of the kind of Universe we live in, how fast it is expanding, and how much matter it contains.

Planck continues to survey the Universe. Its next data release is scheduled for January 2013 and will reveal the cosmic microwave background in unprecedented detail, the opening act of the cosmic drama, a picture of the beginning of everything.

You can read the full news story on the ESA website.