[The Epoch Times, September 07, 2023](Compiled and reported by Epoch Times reporter Lin Da) The moon is the most familiar celestial body for amateur astronomers, and some details of it can be observed with common astronomical telescopes. Still, there are many lunar features unfamiliar to readers. According to the BBC report, 10 of them will be listed below for readers.
Langlun crater. (James Stuby/NASA)
When the Moon is between new moon and first quarter, look to its right with binoculars and you’ll see a bright spot on the eastern edge of the Mare Fecunditatis (Mare Fecunditatis), Langrenus. Craters are craters. The “Mare of Abundance” is the mare (the low-lying plain on the lunar surface) in the southeastern part of the lunar front.
Named after a Belgian cartographer, it is 133 kilometers wide and 4.5 kilometers deep. Viewed with medium to high magnification telescopes, it is a fascinating object, an oval shaped crater with a central mountain peak and six platform structures on its inner walls.
But its oval shape is an illusion. Because of its proximity to the edge of the Moon, we see it from an angle and it appears to be squashed. If you flew over the crater like the Apollo astronauts, you’d see it’s round.
2. Messier and Messier A craters
Messier (left) and Messier A (right) craters photographed by Apollo 11. (NASA)
Slowly move the telescope from Langlun crater to the northwest of the moon. Right below the Taruntius crater (Taruntius), there are two small craters side by side.
They are the Messier and Messier A craters (Messier, Messier A), named after the famous cataloger of deep sky objects Charles Messier (Charles Messier).
The larger of the two, Messier, is also an unassuming crater at 14 kilometers wide, while Messier A is one of the most interesting craters on the Moon, as two bright rays emanate from its western flank like a star Like the tail of a tiny comet. These rays are most visible when the Moon is at or near full and illuminated overhead by the Sun.
Like the intriguing rays from bigger “celebrity” craters like Copernicus and Plato, they’re made of dust and rock fragments that splashed on the Moon as the craters formed.
3. Spitsbergen Mountains
The Spitsbergen Mountains as seen by the Lunar Reconnaissance Orbiter. (NASA/Lunar Reconnaissance Orbiter)
There are some impressive mountains on the Moon, jagged and soaring, that can be seen with a telescope or even ordinary binoculars. But the moon is also dotted with more isolated peaks.
If you look towards the east coast of Mare Imbrium, you will see Montes Spitzbergen, a separate mountain range, above Archimedes crater. It is 79 kilometers wide and looks like an arrow pointing west.
The peaks are thought to be remnants of lava-covered formations billions of years ago when Mare Imbrium, a vast lava plain, formed.
Viewing with a high-magnification telescope is best when the lunar cycle is just past its first quarter, when it is closest to the celestial divide (the dividing line between day and night on the lunar surface) and casts a shadow over the lava plains on which it stands Sharp shadows.
4. Pico Mountain
Mount Pico (upper left) and nearby Unnamed Mountain (lower right) as captured by Lunar Orbiter 4. (James Stuby/NASA)
Mount Pico (Mons Pico) is also an isolated lunar mountain, named after the Spanish “peak”, located in the northern part of the Lava Plain of the Rain Sea and the southern part of the Plato Crater. It is 24 kilometers wide and 2.4 kilometers high at the top of the mountain, shooting straight into the dark lunar sky.
The scene seen through the medium and high power telescope is amazing. The oblique light of the sun casts a long shadow behind it, like Mount Everest.
In fact, while Mons Pico was once jagged like most lunar mountains, it has been worn down by micrometeorite impacts over tens of millions of years and is now more of a domed mountain than jagged.
5. Eradotheus Crater
Eratothetheus crater, photographed by Apollo 12. (NASA)
Eratosthenes may be one of the most dramatic craters on the Moon, but like many celestial objects, it’s often overlooked, overshadowed by its larger, more spectacular neighbors.
To the west is the massive, light-splattering Copernicus crater, while the Apennine Mountains (Apennine Mountains) wind its way to the northeast, and the 60-kilometer-wide Eratosthenes crater is easily visible with binoculars. Its breathtaking appearance can be seen even more under the astronomical telescope.
At high magnification, you can imagine yourself looking down on it from the Artemis capsule orbiting the moon, and you can make out many of its features: its hut-shaped central peak, its uneven terrain scattered with smaller craters, mountain cliffs with platforms.
6. Straight wall
The “straight wall” as photographed by the Lunar Reconnaissance Orbiter. (NASA)
Rupes Recta has been called the “straight wall” by generations of moon watchers, also known as the “moon creek”, and is only clearly discernible when the light and dark line sweeps across it.
The straight wall is located east of Birt and looks like a short straight line. When the sun is on its west side, the straight wall is a bright scratch on the dark lunar surface; when the sun is low on the east side, the straight wall is like a black line drawn with charcoal on the moon’s gray face.
The 120-kilometer-long, 0.3-kilometer-high feature was once thought to be a towering cliff, but today we know it to be a fault in the Moon’s crust, a slope of just 10 degrees.
7. Schiller Crater
Schiller Crater as seen by Lunar Orbiter 4. (James Stuby/NASA)
Scan the lunar surface with a telescope and you’ll see that most impact craters are round. But sometimes you see something different, and Schiller is one of them.
It is located southwest of the lunar front, not far from the famous Tycho crater (Tycho), very close to its southern edge.
Schiller Crater is 179 kilometers long and is a long, thin scar left by multiple objects hitting the Moon simultaneously at low angles.
Telescopes showed that it was wider at one end than the other, like a bowling pin, with a ridge in the center of the narrower part.
8. Rainbow Bay
Rainbow Bay as seen by the Lunar Reconnaissance Orbiter. (NASA/LRO)
High on the northwest coast of the vast “Sea of Rains”, there is a semicircular bay called Rainbow Bay (Sinus Iridum), which is the remains of a crater and was later flooded by lava, leaving only the jagged northern edge from which protruding from the cooled basalt. Rainbow Bay is a favorite of many moon watchers.
Although it can also be seen with binoculars, the view through astronomical telescopes is staggering. The floor of the bay, which at other times would have looked as flat as paper, now reveals countless folds.
9. Eddington Crater
Eddington crater as seen by Lunar Orbiter 4. (James Stuby/NASA)
Near the western edge of the Moon, to the left of bright Aristarchus, lies Eddington, or rather, what remains of it.
The 134-kilometer-wide crater was once a complete feature, bordered by a ring of jagged rocks that punctured the moon’s starry sky.
But when a tsunami of lava poured into the crater from the south, parts of the crater were covered.
The crater remnant is interesting to see with a telescope because of some subtle, challenging features on its floor, including a very small “ghost” crater and a shallow trench.
It is named after British astronomer and author Sir Arthur Eddington.
10. Oriental Sea
Eastern Sea taken by Lunar Orbiter 4. (NASA)
We are lucky to have the moon in the sky to admire though. Yet again, we’ve been tricked into not seeing an amazing sight because it’s hidden from our frontal view of the Moon, the Mare Orientale around the western edge of the Moon.
The Oriental Sea is a dark plain, surrounded by three concentric ring-shaped mountain ranges. The diameter of these mountains is more than 900 kilometers. Seen from above, it looks like a bullseye.
Unfortunately, due to the lunar libration (the moon’s wobble relative to the earth), we can only see a part of the eastern sea. Even when the libration briefly shifted it into view, all we could see of Mare Orientale was a dark, elongated blotch on the edge of the lunar surface, with some faintly glowing ridges surrounding it.
If Mare Orienteur had formed on the Earth-facing side of the Moon, it would have become a prominent feature on the lunar surface, appearing like a blood-red eye looking down on us from the sky during a total lunar eclipse. ◇#
Editor in charge: Sun Yun
