View Full Version : Getting from a blob to the orbital parameters of a KBO

2012-May-26, 11:24 AM
Will the CosmoQuest team at some point write an article outlining how you process the markings that we make? I mean, how do you get from a marked blob to determining whether it is nothing, a KBO, a variable star or an asteroid? I would certainly find that very interesting. I've looked at various pages here but haven't found anything yet. If there is an existing description and I just missed it, I'd be grateful for a link.

2012-May-26, 12:41 PM
That would be great! I think they need the kbo to be marked in several (probably 3 at least?) images, taking from each of them their position in the sky in a given time. What I surely don't know is how they compute the distance of the kbo from the sun, do they infer it from the velocity computed in the previous step deducing the full orbit from there or does it have something to do with it's brightness?

2012-May-27, 02:56 AM
I'm not sure how they're doing it, but the typical way to do it is to get at least 3 observations (3 is required, several more is desirable) and do a curve-fit (ie, guess and check). Very basically speaking, you just try different orbital elements until the observations line up with the orbital model. With each new observation the margin of error is significantly reduced. I imagine a computer algorithm searches through our marks at different time periods and tries to 'connect the dots' for 3 or more observations, subject to certain sanity checks. If a reasonable orbital path is found, it is sent for human verification. If a mark can't be connected to anything else, it's assumed to be erroneous.