It's a big week for astronomers, who have an exciting new dataset to play with courtesy of the Planck Space Observatory, which is currently surveying the skies while orbiting the L2 Lagrangian Point some 1.5 million kilometres from Earth.
Planck's most important goal is to measure the cosmic microwave background, the echo of the Big Bang, in unprecedented detail. In fact, it's unlikely that any future spacecraft will do better. That's because the quality of the final data depends on how well astronomers can subtract nearer objects from the background rather than on the inherent resolution of Planck's instruments themselves. Whatever picture emerges is likely to be as good as it gets.
But the Planck mission has other goals too. Astronomers want to use it to build up a map of galaxy clusters on huge scales, to spot instances of gravitational lensing of the CMB and to look at the Milky Way, the planets and the Sun.
Planck has been collecting data continuously since 13 August 2009 and has almost completed three surveys of the entire sky.
This week, the Planck Collaboration of over 200 scientists from around the world release a first set of data early. They're doing this so astronomers can train other instruments on any objects of interest.
In particular, they want to give the Herschel infrared space observatory a chance to peak at any goodies Planck uncovers. Herschel was launched with Planck and is also orbiting L2 cooled by liquid helium which is gradually boiling away. Consequently, Herschel has a limited lifespan of only 3 years, which it is already more than half-way through.
The Planck Collaboration has released its data in 23 papers placed on the arXiv this week. It's clear the data is beginning to throw new light on mysteries such as the strange emissions from dust in the Magellanic Clouds and the properties of the interstellar medium in our galaxy.
But it's also clear that we're going to hear a lot more about Planck in the coming years. I've placed links to all the new papers below, in case you want to get a head start.
arxiv.org/abs/1101.2032: Planck Early Results: Properties of the interstellar medium in the Galactic plane.