The total brightness of an object as a function of time is called it’s lightcurve;the parameters to be determined from lightcurve observations are the object’s shape, its rotational state, and the scattering properties of its surface.
I didnt write that, some genius did that has far better a way with words than I. An interesting thing, a lightcurve is. Based solely on global structure; the reflected light is the only insight into the life of an asteroid. How that global structure came to be is a tale in its own.
And it’s one thing to generate a lightcurve, heck I hav’nt even managed one yet. But to invert it? That’s purely preposterous. Or is it?
I mean you view an object(asteroid namely); your eye/medium detects the electromagnetic radiation reflected from the source, and it creates an image. This image is not only based on bright and dark regions, but specific values for those bright and dark regions, and where they are located.
So a sinosudal lightcurve of an object tells you about what its rotational period is and maybe where the objects pole resides based on what and where objects appear brighter and dimmer, and through that we can determine when we would see those features appear again on a trend. But the issue here is, how would one go about taking a few magnitude values, and turn it into a triaxial model?
Well apparently it’s very possible, and has been theorized for nearly a century. Only now, with modern computational capabilities, complex algorithms are easily accessed and allows even the most inexperienced of astronomers(like myself) to perform these complex tasks. Programs like MPO LCInvert take the data figures given and produces a basic figure of general volume and shape, along with basic convex and nonconvex features. These features are derived from the Disc-integrated lightrcurves(disc-integration being a way of finding the approximate volume of a non-uniform three dimensional object)
And yes, I know I lied about blogging more. But who really reads this crap anyways.(well…..besides me.)
By William F. Bottke; et al.
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