Kitt Peak Nightly Observing Program
Splendors of the Universe on YOUR Night!
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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.
Theophilus is a prominent impact crater that lies south of Mare Tranquilitatis, and northwest of Mare Nectaris. It partially overlaps its neighbor of similar size, Cyrillus. To the east is the smaller crater Mädler. Theophilus was named after the 4th-century Coptic Pope Theophilus of Alexandria. The rim of Theophilus has a wide, terraced inner surface. It is 4,200 meters deep. The crater formed sometime 3.2 to 1.1 billion years ago. It has a striking central mountain, 1,400 meters high, with four summits, surrounded by a mostly otherwise flat floor. The Apollo 16 mission collected several pieces of basalt that are believed to be ejecta from the formation of Theophilus.
Although we cannot see any of the materials left behind at the Apollo 11 landing site, we can still look at the spot on the Moon where the mission touched down and know, that humans first walked on the Moon in that location. There are a few images of the Apollo landing sites taken by NASA’s Lunar Reconnaissance Orbiter. Apollo 11 landed in Mare Tranquilitatis, also known as the Sea of Tranquility. The landing site is known as Tranquility Base.
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.
Jupiter and the Galilean Moons
Jupiter is the largest and most massive planet in our Solar System. All of the other planets combined would not have as much mass as Jupiter. In even a small telescope, some of Jupiter’s stripes can be seen. Jupiter’s darker stripes are known as bands, and its lighter stripes are known as zones. Swirling storms appear as spots—sometimes visible through telescopes. Jupiter’s famous Great Red Spot is generally visible when its on the side of Jupiter facing toward Earth.
Jupiter’s four largest moons are known as the Galilean Moons, named for Galileo, who was the first astronomer to study them in depth and determine that they were orbiting Jupiter. Their individual names are Io, Europa, Ganymede, and Callisto—in orbital order from closest to Jupiter to furthest out. Ganymede is the largest of these four moons, and is the largest moon in our Solar System. Io, the closest of these four moons to Jupiter, is the most volcanic world in our Solar System. Io is home to hundreds of active volcanos. Its neighbor, and the next furthest from Jupiter of the four, Europa, is a dramatic contrast to Io with its icy surface. Europa is covered by water, which is frozen solid at the surface. The furthest our of the four, Callisto is a fascinating world in our Solar System because it is so utterly geologically dead. Without weather, moonquakes, volcanism, or any other surface-altering processes, Callisto’s surface is billions of years old—a kind of record of the history of the Solar System.
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.
On the eastern bank of the Mare Humorum lie a trio a satisfyingly concentric rilles.
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.
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