NASA will delay the launch of its Psyche asteroid mission, an operation that is designed to explore a metal-rich asteroid and test optical communication technologies. Due to the late delivery of the spacecraft’s flight software and testing equipment, the agency said it lacks the time required to complete testing ahead of its remaining launch period this year, which ends Oct. 11.
As the mission team at NASA’s Jet Propulsion Laboratory (JPL) began testing the system, a compatibility issue was discovered with the software’s testbed simulators. In May, NASA shifted the mission’s targeted launch date from Aug. 1 to no earlier than Sept. 20 to accommodate the work needed to correct the issue. Though the issue with the testbed has been identified and corrected, there is not enough time to complete a full checkout of the software for a launch this year.
Illustration of Psyche spacecraft with five-panel array. Courtesy of NASA/JPL-Caltech/Arizona State University/Space Systems Loral/Peter Rubin.
“Flying to a distant metal-rich asteroid, using Mars for a gravity assist on the way there, takes incredible precision,” JPL Director Laurie Leshin said. “We must get it right. Hundreds of people have put remarkable effort into Psyche during this pandemic, and the work will continue as the complex flight software is thoroughly tested and assessed. The decision to delay the launch wasn’t easy, but it is the right one.”
The mission seeks to study the Psyche asteroid, which appears to be the exposed nickel-iron core of an early planet. Current technologies cannot see or measure Earth’s core directly, making Psyche a potential window into the history of collisions and accretion that created terrestrial planets.
The spacecraft features a solar-electric propulsion chassis built by Maxar Technologies. Rather than using traditional rocket fuel, it will gradually build up speed using ion propulsion. Electricity from the space probe’s solar panels will power a Hall thruster. Xenon gas is converted into xenon ions, which are expelled from the spacecraft to provide thrust — slow at first but building steadily as Psyche accelerates.
The Psyche spacecraft also features a scientific payload that includes a multispectral imager, a gamma ray and neutron spectrometer, and a magnetometer. The multispectral imager is composed of a pair of cameras equipped with filters and telescopic lenses to capture images of the Psyche asteroid’s surface at different wavelengths of light. The data from these measurements will provide information about the mineralogical composition of the Psyche asteroid while also providing a topographical map of the surface that will allow scientists to examine clues as to the asteroid’s history.
The magnetometer and the gamma ray and neutron spectrometer will also serve to provide clues about the asteroid’s composition and history, with the magnetometer potentially being able to prove the asteroid’s origin as a planetary core. The spectrometer provides elemental information by examining gamma rays and neutrons emitted from the asteroid as a result of energetic protons from cosmic rays colliding with its surface.
Additionally, the mission will test laser communication technology that encodes data in photons at near-infrared wavelengths to communicate between a probe in deep space and Earth. The method provides significantly more data in a given period of time than radio waves are capable of. Radio will serve as the primary mode of data transmission and will act as a failsafe should the laser communications encounter problems.
The mission’s 2022 launch period, Aug. 1 through Oct. 11, would have allowed the spacecraft to arrive at the Psyche asteroid in 2026. There are possible launch periods in both 2023 and 2024, though the relative orbital positions of Psyche and Earth mean that the spacecraft would not arrive at the asteroid until 2029 and 2030, respectively. The exact dates of these potential launch periods are yet to be determined.