Kitt Peak Nightly Observing Program
Splendors of the Universe on YOUR Night!
Many pictures are links to larger versions.
Click here for the “Best images of the OTOP” Gallery and more information.
Copernicus is a large, conspicuous crater located in the Oceanus Procellarum (Ocean of Storms). It has extensive rays of ejecta spanning hundreds of kilometers from the rim of the crater. This crater is likely to be only hundreds of millions of years old—young for a lunar crater.
Because of its very smooth, dark floor, Plato is a very distinct crater, seen just north of Mare Imbrium. Plato is 101 km across, and the peaks of the rim rise 2,000 meters above the floor.
Proclus is a very bright crater just west of Mare Crisium. Its bright rays radiate in mostly 3 directions. To its west is Palus Somni—the Marsh of Sleep.
Tycho is a prominent crater on the Moon—but it doesn’t stand out because of its size. At 85 km in diameter it is one of thousands of craters on the Moon its size and larger. Tycho stands out because of its rays. Crater rays are formed by ejecta—dust and debris ejected from the surface during and impact event, that spreads upwards and outwards, and eventually settles back down on the surface to leave behind radial spikes around newly formed craters. Prominent and extensive rays suggest that a crater is fresher, or more recently formed. Tycho may be as young as 108 million years old. That may sound old, but craters on the Moon can remain for billions of years.
Mare Crisium is distinctly seperated from all of the other maria on the near side of the Moon, making it easy to distinguish. This round feature on the Moon is nearing the eastern limb, and so, is severly foreshortened—meaning, we are not looking at it straigh on, but at an angle.
The Mare Imbrium Impact Basin formed when a large object crashed into the Moon 3.9 billion years ago. subsurface lava rose to flood the giant crater, eventually solidifying into a younger, smoother terrain. Prominent features of Mare Imbrium include the crater Plato to the north, with a dark crater floor; Sinus Iridum (meaning Bay of Rainbows) to the northwest, with the Montes Jura mountain range forming a distinct C-shaped knob on the edge of the mare; and the 3 mountain ranges—Montes Alpes, Caucasus, and Apenninus—that mark the eastern edge of the mare.
Also known as a twilight zone, a terminator is where the shadow of night and the light of day come to meet on a planetary body. At the edge of where the Sun’s light reaches, the terminator is constantly moving as the Moon rotates. When observing the Moon, many features are best observed when they are near the terminator, where shadows are long and plentiful. The shadows provide higher contrast between surface features.
The mountain range Montes Alpes is one of the prominent mountain ranges along the eastern border of Mare Imbrium. The range is named for the Alps on Earth, and the peak Mons Blanc is named for the tallest peak in the Alps of Earth—though Mons Blanc is actually the 3rd tallest peak of the Lunar Alpes. The range culminates to the south in the Promontorium Agassiz. To the north, the range terminates just shy of dark-floored crater Plato.
The Montes Apenninus, named for the Apennine Mountains in Italy, is a mountain range along the southeastern rim of the Mare Imbrium Impact basin (Sea of Showers). The Montes Apenninus contain some of the tallest mountains on the Near Side of the Moon.
Your Telescope Operator and Guide. Thank you for joining me this evening! See you soon!!
The web page for the program in which you just participated is at
Nightly Observing Program. Most of the above images were taken as
the Overnight Telescope Observing Program. For more information on this unique experience please visit Overnight Telescope Observing Program.
Copyright © 2019 Kitt Peak Visitor Center