Potential Evolution of the Aura Mission
System Analysis
[Updated September 2026]
The Aura satellite and its instruments are in good/excellent health, having aged well. This status is expected to continue through the next few years. Insufficient power generation by the solar array is conservatively predicted to be the life-limiting factor for the Aura satellite and instruments by mid-2028. However, there is the possibility of a daily spacecraft maneuver, called “pointing for power”, to align the solar panels with the sun, so that the Aura satellite may continue beyond 2028.
From launch in 2004 through early 2023, the polar sun synchronous orbit of the spacecraft had been kept stable and repeatable through periodic spacecraft maneuvers (i.e., inclination adjust, IAM, and drag make-up, DMU, maneuvers), which require fuel to maintain Aura’s position in the A-Train constellation of satellites. The final IAMs were done in April 2023 to save remaining fuel. Consequently, the spacecraft is slowly drifting over time. The final DMUs were performed in January 2023, so the spacecraft is slowly losing altitude, but only a few kilometers by the end of the mission.
An indicator of the drift is the mean local time (MLT) crossing of the spacecraft over the equator during the day. The graph shows the temporal evolution of this drift, which was <15 min through late-2024, ~30 min by mid-2025, and an hour by mid-2026. It is projected to be ~105 min by September 2027 and ~150 mins by August 2028. Overall, this amount of drift is minor from the perspective of data quality for all MLS and OMI data products. That is, the MLS and OMI instrument teams are able to account for this minor drift in the data product retrieval algorithms.
As the Aura orbit continues to drift, the MLS and OMI teams account for changes in the solar beta angle in their retrieval algorithms so that data product quality remains minimally affected. In addition, the OMI solar aperture is no longer facing the sun to obtain a daily solar irradiance measurement to calibrate OMI solar science data. To ameliorate this issue, daily attitude (yaw) maneuvers, which began in July 2026, now align the solar aperture. This method will maintain the view of the sun in the same manner as the original mission parameters until August 2027.
Aura at 20 Years
Launched in 2004, the Aura mission has been nothing short of transformative for scientific research and applied sciences. Bryan Duncan, Aura's Project Scientist reflects in celebration of the mission.
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