Last week, NASA’s Jet Propulsion Laboratory (JPL) in California received a package, which is more important than the small number of Amazon impulse purchases that appeared at most of our doors. JPL has delivered the Psyche spacecraft from Maxar Technologies, and is currently in the process of final assembly. Next year, this piece of hardware will take a SpaceX rocket into orbit, and then go to the asteroid belt to study its namesake, the metal-rich asteroid 16 Psyche.
JPL is filming the August 2022 launch for Psyche, which will be launched during a nearly four-year journey in the asteroid belt between Mars and Jupiter. Along the way, it will pass within only 500 kilometers from Mars. Then, it reaches 16 Psyche, the heaviest known M-type asteroid, which itself only accounts for 1% of the mass of the asteroid belt due to its main iron-nickel composition. Scientists believe that Psyche is the bare core of the protoplanet. It collided with another celestial body in the distant past and stripped its skin.
It is impossible for NASA to miss the opportunity to study planetary nuclei up close, even planets that have been exposed to space for billions of years. The agency selected Psyche as part of the “Discovery” program in 2017. Tasks under the “Discovery” banner are cheaper than those in the “New Frontier” or “Flagship” programs, which can cost billions of dollars. Psyche is expected to cost approximately $117 million, including a launch on the SpaceX Falcon Heavy rocket.
JPL’s newly constructed structure is the so-called solar propulsion (SEP) chassis. This large box module accounts for more than 80% of the total mass of the spacecraft and includes fully integrated propulsion, navigation, thermal and electrical systems. Now, JPL engineers complete the spacecraft’s work by integrating communications, scientific instruments and other systems. Psyche will reach its destination with the help of the SPT-140 engine, which is a Hall-effect thruster that uses solar energy to accelerate xenon ions to generate thrust. Its thrust is not great-the SPT-140’s thrust is measured in micronewtons-but it can accelerate continuously for a long time.
Psyche will use three instruments to study asteroids: using a multispectral imager to take photos of the surface, a gamma-ray spectrometer to analyze the asteroid’s elemental composition, and a magnetometer to measure its magnetic field. The image above is just an artist’s rendering, so we don’t know what the spacecraft will find when it reaches the asteroid of the same name. In any case, this mission may change our understanding of planet formation.