[dard]

I work on the NEO Surveyor space telescope, doing orbit simulations of asteroids/comets and predicting expected observations of objects like these.

If you look: https://www.minorplanetcenter.net/db_search/show_object?utf8...

You will see this was actually spotted back in 2014, but only seen for a few days. When an object is only observed for a few days we generally cannot compute an orbit for it, there is just not enough data to pin it down. However during this current pass of it (the last time it will come by for at least a few centuries), we have enough observations to pin its orbit down. Note that a lot of this is automated nowadays, with automatic observation and "interesting" objects being flagged automatically. There are a lot of small rocks up there (sub 100m).