Planck satellite team uncovers secrets of the universe

The international collaboration of scientists from 15 countries is presenting more than 25 scientific papers on January 11 in Paris, France, on the first results from the Planck mission. Launched in 2009, the Planck satellite is probing the entire sky at microwave wavelengths from 0.35 millimetre to one centimetre. By measuring the cosmic microwave background -- the oldest source of light in the Universe -at these wavelengths, Planck has provided an unprecedented view of the sky.

Amongst the results is the Early Release Compact Source Catalogue, a guidebook of 10,000 extraterrestrial objects that, while appearing unremarkable through optical telescopes from Earth, may provide vital information about the structure and evolution of the Universe.

"In addition to studying the microwave background, Planck maps the 'foreground' emission from our own galaxy and all the stuff between here and the background," says UBC astronomy professor Douglas Scott, who led the UBC team that helped develop software to analyze and calibrate the vast amounts of data before they were used to create maps of the sky.

"This new information will help scientists learn about the coldest clumps of gas and dust where stars are forming, the properties of unusual forms of cosmic dust, huge clusters of never-before-seen galaxies, and how dust-filled galaxies evolve over the history of the Universe," says Scott.

Planck is a European Space Agency mission, with contributions from other agencies including the Canadian Space Agency (CSA). The CSA supports two Canadian research groups based at UBC and at the University of Toronto.

The UBC team consists of Prof. Scott and research associates Adam Moss, Jim Zibin and Andrew Walker in the Dept. of Physics and Astronomy.

Highlights from the latest research include:

•  A new list of the coldest clumps of gas and dust within our own galaxy: Planck's multi-colour survey allows these objects to be picked out easily. Dense cores of dust and gas were found with temperatures as low as just seven degrees above absolute zero (or -266 degrees Celsius). Now that their locations are known, follow-up studies with other telescopes will help understand how these clouds are turning into stars.
• Strong evidence for the existence of what astronomers call "anomalous" dust: interstellar grains of material that behave in an unexpected way, the anomalous dust emits a different light spectrum from other thermally emitting grains. The most likely explanation is that the spectrum peaks at such short wavelengths because dust particles are spinning billions of times a second.
• Clusters of hundreds of galaxies discovered through their effect on the cosmic "background": This "SZ effect," named after Russian astrophysicists Rashid Sunyaev and Yakov Zeldovich, results from the scattering of the background by hot electrons in the clusters. This action is akin to putting a coloured filter onto the microwave sky, altering the spectrum in the direction of the cluster. Planck's combination of multiple wavelength bands has allowed the detection of about 200 clusters. The Cosmic Infrared Background is a glow at infrared and microwave wavelengths, coming from the total light emitted by dust across all the galaxies in the Universe. Planck allows astronomers to study the evolution of these galaxies, by comparing variations across the sky among different wavelength bands.