Status of 'The NEAR Challenge' (21 March, 1999)

Tom Van Flandern [Reprinted from the Meta Research Bulletin Volume 8, Number 1, 21 March, 1999]

A programming error prevented the spacecraft from entering orbit around asteroid Eros as planned on January 10. The rendezvous and orbit insertion have been postponed until February 14, 2000.

The NEAR team reports no satellites "larger than 100 meters" showed up in their fly-by pictures. Our NEAR challenge predicted "at least three moons larger than 1 meter". The presently observed limit is nowhere near setting a useful constraint with respect to our challenge. However, it is apparent that Eros has an extremely irregular shape. It looks like a bent icicle at some orientations. That raises the question whether any stable orbits exist for such an irregular gravity field. That may be determined over the next few months. If no satellite orbits are stable, then we must look for former moons that have gently impacted on the surface, often rolling great distances and leaving visible roll marks in the process.

The chances of getting intact objects on the surface from non-satellite collisions are nil because the rms speeds involved are typically 5,000 m/s for field asteroids, but only a few m/s for satellites. Field asteroid speeds would result in highly destructive, crater-forming impacts. So finding surface "satellites" when NEAR goes into orbit around Eros next year is still a good diagnostic between the standard model and the eph.

Several interesting wire diagram models of Eros' eccentric shape may be found on the The Johns Hopkins University Applied Physics Laboratory web site at http://near.jhuapl.edu/iod/19990201/index.html. According to the APL site, the shape of Eros "has been compared to a shoe, a battered boat, or a peanut."