Last week, the OSIRIS-REx spacecraft continued on its new post-EGA trajectory toward Bennu. A REXIS Solar X-Ray Monitor testing and calibration activity began Oct. 9 and ran through Oct. 12. On Oct. 7, the spacecraft’s communications downlink rate decreased to 40 kbps from 200 kbps. The spacecraft continues to communicate back to Earth through its low gain antenna (LGA).
As of Oct. 16, the OSIRIS-REx spacecraft is approximately 12.9 million km from Earth and has traveled around 1.03 billion miles since launch. It has another 970 million km to travel before it reaches Bennu.
The mission’s instrument teams and science working groups continue to actively process EGA science observations for the OCAMS, OVIRS, OTES and TAGCAMS instruments. Early indications show outstanding performance of the instruments, giving confidence that they will operate as designed at Bennu. Although the EGA maneuver and subsequent observations went smoothly overall, the science operations team is looking at lessons learned from EGA on both planning and ground tools to assess whether there are further improvements that could be made for Bennu operations.
As of Oct. 9, the OSIRIS-REx spacecraft is approximately 8.8 million km from Earth and its one-way light time is around 30 seconds.
Following a successful Earth Gravity Assist on Sept. 22, the spacecraft engaged its OCAMS and TAGCAMS cameras and OTES and OVIRS spectrometers on Sept. 22, Sept. 25 and Sept. 28 to observe the Earth and Moon. The instruments operated nominally and the mission team was able to use the opportunity to exercise its science operations procedures and calibrate the spacecraft’s instruments. Images and spectra of Earth and images of the Earth and Moon were also released. A final day of observations is scheduled for Oct. 2.
The mission’s navigation team determined that the spacecraft’s post-EGA trajectory was on course as planned. As a result, the trajectory correction maneuver (TCM-6) scheduled for Oct. 4 was cancelled.
On Friday, the OSIRIS-REx spacecraft completed its planned Earth Gravity Assist.
Last week, the OSIRIS-REx spacecraft maintained nominal operations as it continued on a trajectory toward Earth for its scheduled Sept. 22 Earth Gravity Assist (EGA). On Sept. 14, the spacecraft’s communications downlink rate increased to 300 kbps from 200 kbps as the spacecraft’s distance to Earth continues to shrink. The spacecraft is currently communicating through its low gain antenna (LGA).
As of Sept. 18, the spacecraft is 2.6 million km from Earth and its one-way light time is around 9 seconds.
This week, OSIRIS-REx’s navigation team determined that the spacecraft’s 23 Aug. trajectory correction maneuver (TCM-3) accurately set the spacecraft on the correct trajectory for its Sept. 22 Earth Gravity Assist (EGA). This means that there will be no need to execute TCM-4 or TCM-5, which were originally scheduled to further target the spacecraft at the optimal EGA aim-point.
Preparations for EGA continue for the team on the ground. In particular, the instrument teams are getting ready for science observations of Earth and the Moon as the spacecraft swings by Earth and continues on a new orbital plane out toward Bennu.
As of Sept. 11, the spacecraft is 6.5 million km from Earth, having traveled 933.9 million km since launch on Sept. 8, 2016.