Reiner Gamma (萊因納伽傌) is a swirling deposit of bright material near Reiner on Oceanus Procellarum. It measures about 70 km east-west, with the central part resembling an oval dome.
In general the lunar surface is lack of magnetic field, but Reiner Gamma is one of the few known anomalies. A model suggests that the early Moon still preserved a weak magnetic field. It happened that some fragments of a low-density comet fell on the Moon and ploughed up the regolith. Their interaction strengthened the local magnetic field while the global magnetic field faded more quickly in time. As magnetic field deflects the charged particles in solar wind which are known to darken the lunar surface, it may account for the brightness of Reiner Gamma against the dark mare background. Another model proposed that shock waves produced from a meteoroid impact on the farside of the Moon may have forced lighter matetials to the location of Reiner Gamma. At present the puzzle of lunar swirls remains unanswered.
發表於 2009-11-21 15:48:23
