Flux-to-Albedo Model
ASTR 3510, Fall 2025 ยท 3-person team project
What it is
How bright an object looks depends on its size, its distance and how reflective its surface is. Reflectivity (geometric albedo) is a clue to what a surface is made of. We built a pipeline that turns telescope images into an albedo estimate.
Method
- Calibration: dark, bias and flat-field corrections on the raw images.
- Aperture photometry: measure the flux of each target.
- Flux ratio to the Sun: compare the measured flux to the sunlight hitting the object.
- Geometric albedo: convert that ratio into an albedo.
Icy moons and the mystery object
We used icy moons with known albedos to calibrate and check the pipeline. The goal was to characterize a mystery object from its measured flux.
Results
- Our model classified the mystery object, asteroid 16 Psyche, as rocky. Its real albedo is about 0.15 and it is more metallic than rocky, which showed the limits of a model with only three categories and a small training set.
- We also found no strong correlation between measured flux and geometric albedo.