Transient lunar phenomenon - Definition and Overview

A transient lunar phenomenon (TLP) is a sometimes inexplicable change of color or shape seen on the surface of the moon. Some may be caused by gas escaping from underground cavities after moonquakes.

In 1866, the experienced lifelong lunar observer and mapmaker Johann Friedrich Julius Schmidt made the claim that Linné crater had changed its appearance, from a normal, relatively deep crater to a mere white patch. A controversy arose and the claim remains unproven. No further changes have been observed in the crater; if true this would not be a transient change but a permanent one.

On November 2 1958, the Russian astronomer Nikolai A. Kozyrev observed an apparent outgassing of vapor near the central peak of Alphonsus crater. He took spectrograms that appeared to show the presence of carbon vapor.

Other near-side craters where TLP have been reported are Aristarchus, Grimaldi, Hercules, Plato, Theaetetus and Thales.

References

• The Kozyrev Observations of Alphonsus, PASP 71 (1959) 46 (http://adsabs.harvard.edu//full/seri/PASP./0071//0000046.000.html)

External links

• "Light Side of the Moon" (http://members.lycos.co.uk/petergrego/ft105.htm) — An article from the Fortean Times for December 1997 by the astronomer Peter Grego
• Transient Lunar Phenomena (and other weirdness) (http://www.planetfusion.co.uk/~pignut/tlp.html) — Essay on TLP followed by links
• Chronological Catalog of Reported Lunar Events, July 1968 (http://www.mufor.org/tlp/lunar.html) — NASA report on TLP sightings from 1540 to 1968