Precise Orbit Determination of MEX Flyby Phobos Using Simulated Radiometric and Image Data.

Area of Science:

• Spacecraft navigation
• Astrodynamics
• Planetary science

Background:

• Navigation cameras are standard on deep space missions, primarily for auto-navigation.
• Image data from Mars Express (MEX) during Phobos flybys exist but haven't been utilized for precise orbit determination due to processing challenges.

Purpose of the Study:

• To investigate the potential of using spacecraft image data for precise orbit determination.
• To explore methods for incorporating image data into orbit determination models.
• To assess the impact of image data on orbit accuracy for deep space missions.

Main Methods:

• Utilized simulated image data to test the feasibility of using image data for orbit determination.
• Applied image data to the orbit determination of the Mars Express spacecraft during a Phobos flyby.

Main Results:

• Image data provide stronger orbital constraints in tangential and normal directions compared to traditional Doppler data.
• Orbit determination accuracy for Mars Express in the tangential and normal directions was significantly enhanced when image data was incorporated.

Conclusions:

• Spacecraft image data holds significant potential for improving precise orbit determination in deep space missions.
• This research provides a foundational reference for processing real image data from missions like Mars Express to enhance both spacecraft and celestial body ephemeris accuracy.