Kepler -- Down But Not Out? Officials Issue Call for Project Submissions

Kepler, the planet-hunting all-star space telescope, may be down but, researchers hope, not necessarily out.

After two of its reaction wheels, important for precise pointing, malfunctioned, NASA researchers are calling for possible project ideas to keep the space telescope going forward.

"If one of the two reaction wheels cannot be returned to operation, it is unlikely that the spacecraft will resume the nominal Kepler exoplanet and astrophysics mission," those behind the mission wrote in a publically-released submission request form.

Not ready to let the $600 million-dollar project go to waste, however, project officials said they are looking for "alternate science investigations that may be performed using Kepler and are consistent with its probably two-wheel performance."

Examples of possible submissions include "improve calibration of intra-pixel responsivity variations, data analysis techniques suitable for extraction of photometry from trailed images or modifications of data collection methods, such as significant changes in the current usage of masks to select pixels for coaddition and downlink."

No funding is available under this call, the agency added.

Trouble first hit Kepler in July 2012 when one of its reaction wheels failed. It was followed in May by a second wheel and, while both exhibited the ability to spin bi-directionally in recent tests, friction levels as a result of the turning remain high, a recent update reported.

"With the demonstration that both wheels will still move, and the measurement of their friction levels, the functional testing of the reaction wheels is now complete," officials said. "The next step will be a system-level performance test to see if the wheels can adequately control spacecraft pointing."

In the case that friction levels remain steady over time, the issue may be corrected in the spacecraft's attitude control system, the researchers explained. However, should this level vary, the wheels will be essentially useless.

Tests focused on Kepler's pointing performance will begin Aug. 8 and continue into the following week in the case that things go well, project managers said, with a determination of whether the device can return to its search for exoplanets due in coming weeks.

Correction: The article previously stated that the first wheel went out in May, rather than July 2012 as it now reads.