Kepler to run out of fuel in the coming months

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After nine years of success, the Kepler space telescope is running out of fuel, which will force an end to the mission sometime in the next several months.

The Kepler team is planning to collect as much science data as possible in its remaining time and beam it back to Earth before the loss of the fuel-powered thrusters means that we can’t aim the spacecraft for data transfer. We even have plans to take some final calibration data with the last bit of fuel, if the opportunity presents itself.

Without a gas gauge, we have been monitoring the spacecraft for warning signs of low fuel— such as a drop in the fuel tank’s pressure and changes in the performance of the thrusters. But in the end, we only have an estimate – not precise knowledge. Taking these measurements helps us decide how long we can comfortably keep collecting scientific data.

They are doing a dance here. If they run out of fuel while collecting data, that data will be lost. If they stop collecting data too soon, however, to transmit it to Earth, they will not maximize the data obtained.

Meanwhile, the next exoplanet hunter, TESS, is scheduled for launch on April 16 on a Falcon 9 rocket.



  • Steve Earle

    Too bad they couldn’t get a refueling bot to it in time.

  • wodun

    Wonder if the orbital dynamics would work for an MEV mission. But then again, maybe they don’t want to extend the lifespan because that just times up money and manpower that could be devoted to whatever they want to do next.

  • Edward

    Kepler was looking at a limited area of the sky. Its mission was a bit different than the TESS mission, which will look at more sky but will emphasize the nearer stars over the more distant stars.

    The following Space News article is from January:

    TESS, like Kepler, will look for exoplanets by detecting very small changes in brightness of stars as orbiting plans cross, or transit, their disks. But while Kepler initially examined a single, small area of the sky in an effort to determine the fraction of stars with planets, TESS will instead perform an all-sky survey, focused on the brightest stars nearest to Earth.

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