One of my favourite space observatories was the Wide-field Infra-red Survey Explorer (WISE), both for the scale of its mission and the shortness of its planned life.  Built to survey the entire visible universe in infrared, it took ten months to image every single part of the sky in detail using its exquisitely sensitive infra-red cameras.  Two operate properly, the most sensitive cameras had to operate at temperatures close to absolute zero, and were packed in frozen hydrogen.  Once the last of this coolant had evaporated away, WISE was given a new mission (and a new name) to use its remaining instruments to map out the Solar System, finding and cataloguing thousands of prevously undiscovered asteroids in near-Earth orbits.

Now, two years later, the data from WISE’s original mission has been released to the public in the form of an online sky atlas.  Anybody wishing to study a region of the sky in infra-red wavelengths needs only visit the project website and enter the required co-ordinates to get access to the original images returned by WISE.  This sort of free sharing of data is common in Astronomy, since most big projects are so big and expensive that they require the funding of multiple governments.  In other words, taxpayers around the world paid to get this data, so it’s only fair that it be treated as a freely available public resource.