SEDONA — On the moon the crater Aristarchus is considered to be the brightest of the major features there. Aristarchus provides a reflection of solar radiation that is twice that of other typical lunar features. This reflection of sunlight makes this crater visible to the naked eye and easy to spot in a small telescope.
However, a large telescope would reveal some surprisingly bright features within it. Aristarchus is an impact crater that can be found on the northwest part of the moon on the side that faces us.
This 25-mile (40 km) wide crater is deeper than the Grand Canyon, about two miles deep, and was named after the Greek astronomer Aristarchus of Samos, who first suggested that the sun rather than the earth was the center of our solar system. The crater lies on the southeast portion of the Aristarchus Plato, an area known for ancient volcanic activity.
One of the more famous volcanic features in this region is called the Sinuous rills, a long winding channel that lava flows through. Fleeting lunar phenomenon has reportedly been observed in that area as well as radon gas emanating from the crater has been detected by NASA’s Apollo 15 when it passed over the crater in 1975.
The fleeting phenomenon reported by professional and amateur astronomers alike has been unusually bright momentary lights (known as transient phenomenon), sometimes electric blue in color, coming from the center of that crater, similar to those seen emanating from crater Plato.
The bright crater Aristarchus is relatively young being formed some 450 million years ago. It is bright, because the solar winds have not had enough time to darken it. Again, illustrating how forces like gravity and the effects of the solar winds are always at work on the moon.
This amazing lunar feature has a central peak created by material released from deep within the lunar surface at the time of the original impact. This peak is the brightest feature there.
In short, I say again that amateur astronomy is subtle, careful observations done with great patience, revealing the mysteries of the universe. This transient lunar phenomenon, I have mentioned, (the flashes of electric blue lights) are rare but they do happen. Capturing one on video or with a still camera can make you famous, in certain circles at least.
But this idea intrigues me, and encourages me to spend time viewing craters, Plato and Aristarchus through a small telescope. This is an opportunity to do some astronomy on full or nearly full moon nights. Crater Aristarchus is one object that readily shows itself on those nights that might otherwise be overlooked due to the brightness of the moon. Many folks I have met, over the years have been eager to explore deep space, with their telescopes, however, most of the “action”, like eclipses, transits, occultations, and lunar phenomenon are things we can observe easily in our backyards.
Former Arcadian Victor C. Rogus (F.R.A.S.) is a fellow of the Royal Astronomical Society, London, living in Sedona, Arizona.