The last time NASA made normal contact with it was on April 4th
NASA scientists are working to save the planet-hunting Kepler spacecraft after it slipped into a state of emergency.
The ageing spacecraft - which has detected almost 5,000 planets - is around 75 million miles away from Earth.
Scientists discovered that it had entered emergency mode at some point last week.
The last time they made normal contact with it was April 4th, when there were no signs of any problems.
The emergency mode means that it is now at its "lowest operational level" and is burning through a huge amount of fuel.
The future of the spacecraft - currently our best chance of finding habitable planets outside our solar system - now hangs in the balance.
The NASA team overseeing Kepler says it entered emergency mode just before it began pointing it towards the centre of the Milky Way.
Its original mission was completed back in 2012, during which it spotted close to 5,000 suspected exoplanets - planets which orbit a star other than the Sun.
Following its success, NASA set it on a new mission called K2, which is an expanded search for other interesting astronomical objects.
This includes hunting for young stars and supernovae.
Over the past few months it has found the most Earth-like exoplanet to date and recorded the first shockwave coming off a supernova: