Source code for this can be found on GitHub.
This is an on-line version of the astcheck program used for identifying observations with known objects. Use the form below to find asteroids that might match the position/motion of objects you've observed.
Suggested quick start: Don't panic! Copy/paste your observations in the large text window below, or click on "Browse" to pick a file containing the astrometry. Then click the "find matching asteroids" button. That will probably be all you need.
The output will show each object, and its motion in arcseconds/hour. After that, you'll see possible matching objects, and their offsets in arcseconds and their motions in arcseconds/hour. You can set a limit for the search radius, and can tell the program whether to use the Minor Planet Center's MPCORB or the Lowell Observatory ASTORB orbit catalog. The latter offers "current ephemeris uncertainty" data. This is not perhaps as rock-solid as it ought to be, but can tell you if the predicted position from the orbital elements is very, very good, or complete rubbish.
You can also show only possible matches with unnumbered objects, useful to those who are already pretty confident that the object isn't easily identified.
If you're still not getting things to work, contact me at pôç.ötulpťcéjôřp@otúlm (modified to baffle spammers).