To determine object, in most cases need and enough, to determine it's orbit. In case of Near Earth Object, most interest parameters, when it was near Earth and period to next approach.
Looks like, astronomer calculated from single point, this object was approached in 2018, which is launch year, because Roadster don't have long running engines (none of space sails or ion engines), so it's orbit don't changed much after 2018.
- Ion engines or space sails could work many years, so it will not be easy to discover start point from just one known point of current orbit.
Looks like, astronomer calculated from single point, this object was approached in 2018, which is launch year, because Roadster don't have long running engines (none of space sails or ion engines), so it's orbit don't changed much after 2018.
- Ion engines or space sails could work many years, so it will not be easy to discover start point from just one known point of current orbit.