On Friday, NASA held a press call to announce that its planned mission to the asteroid Psyche, planned to launch this autumn, was indefinitely. While the spacecraft is ready and delivered to Kennedy Space Center, there have been delays in validating the software that will drive the mission as it operates in remote regions of the solar system.
That delay has pushed mission preparations past the point where the launch window is closed due to alignment changes in the body Psyche will pass on its journey to the asteroid of the same name. NASA is saying that a mission review will evaluate all options from cancellation to delaying the mission until the next window opens. Problematicly, the launch of Psyche includes a ride-along to a separate asteroid mission called Janus, which has its own launch windows, so the review needs to include NASA’s entire Discovery mission program more broadly. Will be
Asteroid Psyche is an unusual body in the Solar System. This is the former core of an object that was large enough to form a core of metallic elements; Since then collisions have stripped away the outer layers of this body, leaving behind an almost entirely metallic thing. Accordingly, visiting Psyche offers an opportunity to improve our understanding of the formation of everything from present-day asteroids to bodies merging to form planets.
And NASA plans to do so through the exact same mission that shared the asteroid’s name. However, the timing of the launch is important. Gravitational effects from the planets will affect how quickly Psyche can take place, and mission organizers wanted to ensure that the probe arrived at Psyche at a point in the asteroid’s orbit where sunlight is conducive to imaging.
As our recent visit to JPL showed, the hardware was ready in time. But there have been problems validating the mission’s software, which combines guidance, navigation and hardware controls. The verification process requires a platform that mimics the hardware on the probe, in some cases through a duplicate of the actual onboard hardware. That test platform was recently completed, and mission planners concluded there was not enough time to fully test the software before the launch window closed.
Psyche is particularly sensitive to its control software as it continues to move through the solar system, powered by a weak-but-efficient ion drive. This requires it to begin operations under its control 70 days after launch, unlike missions that can achieve rocket-powered maneuvers from low Earth orbit, followed by some software features before they become critical. They hang around for months to years.
Without the launch of Manas, the Janus mission is clearly going to be delayed. It is unclear at this point whether that mission’s future launch window coincides with a proper window to launch Manassas.
To figure out what to do next, NASA will set up an external review committee that will evaluate what went wrong and what options are going forward. Multiple future launch windows are available, and delaying the mission at this point is the most likely option. But the people on NASA’s press call were remarkably hesitant to take any options off the table, including canceling the mission altogether.
In any case, given that the appraisal panel hasn’t been staffed yet, it will take us some time to know what happens next.