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To get orbit details of a large number of objects Two line elements (TLE) datasets are often used. However since the only value that's related to mass in the TLEs is the BSTAR drag term how could I find the mass of each orbital object?

I assume I could look it up from launch details (although if this is the solution shouldn't this value be included in the TLEs?) but this seems cumbersome also what about objects that are created from collisions between satellites. Is there a database somewhere that includes the mass of each object?

ThePlanMan
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According to a yahoo group conversation, they can measure effects of solar radiation pressure on the object's orbit. The force would be roughly proportional to the area, and the resulting acceleration is inversely related to the mass.

See: https://groups.yahoo.com/neo/groups/mpml/conversations/topics/31398

I presume this is how they estimated the density of WT1190F.

Guy Vandegrift
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  • This sounds interesting though the link is not visible without logging in. Could you post the whole article please Yahoo groups are going to dissapear at the end of the year (2020)? – Puffin Oct 28 '20 at 19:43
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I don't know of any way to accurately determine the mass of a piece of debris on orbit without knowing the material beforehand. Their mass is much too low to use gravitational influence as a measure and I don't think the "usual" method for small asteroids applies. This would be assuming an albedo to determine the size by the amount of light it reflects, and then determining the mass by assuming (again) a density.

This fails with debris. Debris tracking is mostly done by Lidar. While the albedo could be determined this way, this would only give you information on the surface, which may be coated for maximum reflectivity or emissivity. For large enough objects they may be able to determine a size by direct measurement. However, the object is likely to be fragile and made of many different materials, rather than solid.

My best guess is that they use an average density of a typical satellite fragment if they have no pre-launch information. I wouldn't assume that is is very accurate.

Rikki-Tikki-Tavi
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