It looks like maybe a drop of water on the windshield. If you look carefully at the trees, roadway or grass, the way they're blurred doesn't seemed to be shared by the object.

The trees are essentially at an infinite distance from the camera (not literally, of course, but with a small, fixed-focus lens there'd likely be no practical distinction between focussing on the trees and on an extremely distant object like the moon, for instance). The object, otoh, looks to me to be on a different plane, which would make it closer (it's not going to be farther than infinity).

The object's apparent luminescence could be credibly attributed to the lights of the oncoming car, imo.

Just one guy's opinion.