NASA’s OSIRIS-APEX spacecraft has just completed a major milestone in its journey to asteroid Apophis. This spacecraft, once called OSIRIS-REx, now investigates Apophis after delivering samples from asteroid Bennu. On January 2, 2024, OSIRIS-APEX emerged unscathed from a close encounter with the Sun.
OSIRIS-APEX ventured 25 million miles closer to the Sun than initially designed to handle. But mission engineers resourcefully reconfigured it. They positioned a solar array to protect sensitive components from strong solar heat. “It’s phenomenal how well our spacecraft configuration protected OSIRIS-APEX,” said Ron Mink, mission systems engineer.
This success is encouraging for the mission team. Between December 2023 and mid-March 2024, OSIRIS-APEX had limited telemetry data due to its proximity to the Sun. By April, the team confirmed its successful navigation through this extreme environment. The spacecraft now operates normally on an elliptical solar orbit.
Surprisingly, some components show improved performance. For example, a camera designed to map Apophis has 70% fewer “hot pixels.” Another, a spectrometer, dislodged a rock sample stuck from the Bennu collection. Amy Simon, OSIRIS-APEX project scientist, said, “The rock in the calibration port appears to have been dislodged.” This implies that enough spacecraft maneuvers and engine burns cleared the obstruction.
OSIRIS-APEX will have five more close solar passes before reaching Apophis in 2029. Its next perihelion, or closest solar approach, is scheduled for September 1, 2024. This pass will bring it within 46.5 million miles of the Sun, roughly half the Earth-Sun distance.
While the first successful perihelion is a positive sign, engineers remain cautious. The cumulative effects of multiple extreme solar encounters are still unknown. Additionally, three Earth gravity assist maneuvers are planned to adjust the spacecraft’s trajectory.
The OSIRIS-APEX team still feels optimistic about it. The spacecraft continues on its unprecedented mission to detail how Earth’s gravity will reshape the “God of Chaos,” Apophis, in 2029. This mission promises to give substantially new knowledge about asteroid dynamics and the defense of the planet.
OSIRIS-APEX’s odyssey presents NASA’s creativity in engineering. It proves a sensitive yet robust design of a spacecraft and its adaptability to new situations. So far, the mission is a testament to the commitment of the team behind this ambitious endeavor.