HDR optical-algorithm co-design of space-based asteroid detection systems based on background radiation priors

Area of Science:

• Astronomy and Astrophysics
• Optical Engineering
• Space Science

Background:

• Mid-infrared (3-5 μm) asteroid detection faces challenges from weak targets and strong zodiacal background radiation.
• Dynamic range mismatch is a significant issue in current detection systems.

Purpose of the Study:

• To propose and validate a high-dynamic-range detection approach for improved asteroid detection.
• To address and mitigate the effects of zodiacal background emission on target visibility.

Main Methods:

• Utilizing a digital micromirror device (DMD) for pixel-level exposure-time modulation.
• Employing a DIRBE-model-based prediction of zodiacal radiation and an on-orbit observation residual equation for background correction.
• Decomposing directional radiance fields into binary mask images to drive the DMD.

Main Results:

• Demonstrated effective suppression of strong zodiacal background radiation.
• Achieved pixel-level dynamic range extension, enhancing target visibility.
• Improved aperture-photometry signal-to-noise ratios from undetectable to detectable levels for multiple stars.

Conclusions:

• The proposed DMD-based method offers a feasible system solution for next-generation asteroid detection payloads.
• Provides a practical reference for suppressing background radiation and extending dynamic range in space observation.