Posted: Wed, Mar 6, 2013, 8:31 AM ET (1331 GMT)
A European astronomical spacecraft launched nearly four years ago is expected to end its mission within weeks when it exhausts its supply of coolant, officials said Tuesday. The Herschel infrared observatory, launched in May 2009 to the Earth-Sun L2 point, cools its instruments with an onboard supply of liquid helium. ESA said Tuesday the spacecraft's supply of liquid helium is nearly exhausted; the agency did not provide a specific date but said it is likely to come in the "coming weeks". The spacecraft has already completed its highest-priority observations, making discoveries form the distant, early universe to planetary systems forming around nearby young stars. Once the spacecraft's helium is exhausted, scientfic observations will end, and the spacecraft will move from the L2 point to a "long-term stable" orbit around the Sun in May.

Related Links:

•  BBC article
•  ESA press release