The OSIRIS-APEX spacecraft remains undamaged after its recent closest approach to the Sun, thanks to a change in its solar panel configuration.
The OSIRIS-REx spacecraft successfully completed its mission to return samples from asteroid Bennu to Earth and is now heading towards asteroid Apophis as part of its extended mission. With this new mission, OSIRIS-APEX will fly within 40 million kilometers of the Sun, which is much closer than originally designed. Scientists believe that several such close approaches are crucial for the spacecraft to stay on course to reach Apophis in 2029, as reported by Space on May 30.
NASA’s OSIRIS-REx spacecraft. (Image: Sci Tech Daily).
OSIRIS-APEX is following an elliptical orbit around the Sun, passing its closest point to the Sun every nine months. Its first close approach occurred on January 2. To prepare for the intense radiation, the mission team compacted one of the two solar panels earlier in December last year to shield the most sensitive instruments on the spacecraft, while the remaining panel faced the Sun to provide power.
This innovative solution effectively protected the spacecraft during the extremely hazardous close approach to the Sun, just as computer simulations had predicted. “It’s impressive how well the new configuration protected the OSIRIS-APEX spacecraft,” said Ron Mink, the OSIRIS-APEX mission systems engineer at NASA’s Goddard Space Flight Center in Maryland.
Telemetry data sent from the spacecraft in mid-March confirmed that it was in good condition. By early April, the spacecraft had moved far enough from the Sun to resume normal operations, according to NASA’s announcement. Scientists and engineers were also surprised to find that the camera onboard was functioning even better after exposure to the high temperatures during this close flyby. MapCam, the camera that previously mapped the colors of Bennu and will do so for Apophis, showed a 70% reduction in blemishes since April of last year, the last time the camera was tested.
Blemishes occur due to prolonged exposure to solar radiation and are a common issue for cameras in space. While these issues are typically addressed with heat from heaters, the OSIRIS-APEX camera recovered naturally thanks to the surge in heat from its close approach to the Sun earlier this year. Team members expressed relief that OSIRIS-APEX remained safe after its most recent close flyby. They are uncertain how the next five close approaches might affect the spacecraft and its instruments. The next close approach is scheduled for September 1, when the spacecraft will fly within 74.8 million kilometers of the Sun, still inside the orbit of Venus and far exceeding its original operational limits.
