By Dr David Whitehouse
BBC News Online science editor
The European Space Agency (Esa) has cancelled its space mission that was to look for planets circling other stars.
Esa has never cancelled a mission before
Over 400 astronomers had written to Esa asking it to keep the 2008 mission.
But budget problems caused by delays in the troubled Ariane 5 rocket have killed the project, as well as the lander segment of a mission to Mercury.
Esa's Dr David Southwood said that cancelling such a mission really hurt.
At a meeting, the European Space Agency's Science Programme Committee (Spc) decided that due to money problems it was forced to cancel the Eddington planet-search mission and reduce the BepiColombo mission to Mercury.
It is the first time that Esa has cancelled a space mission.
Eddington was a state-of-the-art programme designed to observe nearby stars and look for planets circling them
The loss of the BepiColombo lander is also scientifically hard to take. Esa, in conjunction with the Japanese space agency, JAXA, will still put two orbiters around rarely-visited Mercury, but having no lander is seen as a big loss to the project.
It was decided that to land on a planet so near the Sun was too difficult in present circumstances.
'Long and painful discussion'
The origins of the budgetary problems are several sudden demands on Esa finances that occurred after the Ariane 5 rocket's grounding in January. This delayed, by a year, the launch of the expensive Rosetta comet lander mission.
A loan of 100m euro was temporarily granted, but it must be paid back out of present resources by the end of 2006.
After what Esa called a "long and painful discussion" it decided that only one new mission could be started at this time, namely the Laser Interferometer Space Antenna (Lisa) Pathfinder.
The mission is the technical precursor to the world's first space-borne gravitational wave astronomical observatory, Lisa. The Lisa mission itself (to be made in cooperation with the United States) is scheduled for launch in 2012.
David Southwood, head of Esa's science programme, is sympathetic to the concerns of Eddington scientists, but said there was little that could be done given the budget problems which, he added, were a result of tighter financial control on space projects these days.
He said the loss of this one mission would not stop Esa pursuing its grand quests.