Since rocketing into space five and a half years ago, NASA's Spitzer Space Telescope has snapped tens of millions of images (see slideshow of Spitzer's greatest hits). But the data flood will slow to a trickle in 2009 as the infrared telescope moves into old age.
In April, give or take a month, the telescope's liquid helium coolant will run out, making its instruments too warm to take useful images. Normally, the telescope must be cooled to just above absolute zero (around 2?K) to stop its own heat from impinging on its results. When the last of its 360 litres of helium is gone, the telescope will heat up to about 25?K and all but two channels on one of its instruments will become unusable.
Full story from Nature News.