A B C shaped lunar surface features, observable through telescope, and/or appearing on orbital photographs


Danny Caes

This page is an experiment, to see if there might be 26 alphabet-letter shaped surface formations on the moon (and perhaps also the numbers from 0 to 9, and the 24 letters from the Greek alphabet).
The source of this experiment is a question from Charles A. Wood, who wanted to know if it would be possible to create an alphabetic list with corresponding telescopic (or orbital photographic) lunar features.

  • A
  • B The B shaped swirl north-northwest of Hansteen. See LO IV-156-h3.
  • C
  • D The D shaped depression Ina at Lacus Felicitatis.
  • E
  • F
  • G
  • H The compact cluster of hillocks in the shape of an inflated H, southwest of Hansteen, at: LAT -12.91/ LON -53.95.
  • I
  • J
  • K The K shaped system of Rimae Triesnecker.
  • L The officially unnamed L shaped mountain west of Lamech, which is called Mons Elbruz by Danny Caes, because the terrestrial Elbruz mountain is also located in the Caucasus range! The lunar L shaped mountain is 'at its best' during Full Moon (a typical bright L!).
  • M
  • N The N shaped system of rimae just north of Ramsden.
  • O (all over the moon; almost every crater, large and small).
  • P
  • Q The Q shaped remains of crater Kies (by Bachmann1).
  • R
  • S
  • T The T-shaped kipuka southwest of Arago E / north-northwest of Arago D, at LAT: 7.89 / LON: 21.93
  • U
  • V The Lunar V north of Ukert M, only observable during local sunrise (a clair-obscur phenomenon).
  • W Curious W shaped formation at (approximately) 37° North/ 56°30' West, southeast of the bowl-shaped craterlet Rumker F. See lower part of Lunar Orbiter 4 frame 163-h2. This could be a Trompe l'Oeil effect (an equivalent of the "Face on Mars" phenomenon).
  • X The Lunar X at Blanchinus, La Caille, and Purbach, which is only observable during local sunrise (a very well known clair-obscur phenomenon). A very interesting telescopic X is the crossing of two rilles on the floor of Palmieri. Another X is the crossing of Rima de Gasparis II with an unnamed rille on the floor of an unnamed crater immediately southwest of de Gasparis itself. There's also a rather large X at Rupes Altai and the pronounced Tycho-ray at Polybius A, known as the Delvau-"X" (from Ron Delvaux).
  • Y
  • Z The peculiar Z shape tendency on the western inner slopes of Aristarchus, which could be a Trompe l'Oeil effect related to the angle of illumination (??). See LPOD Catching some ZZZ


The numbers from 0 to 9

  • 1
  • 2 The bright and distinct appearance of a 2 (a number two) at the eastern parts of Deluc and Deluc D. This peculiar effect is visible when the morning terminator runs at 1° 30' West (say: 1° to 2° West, over Oppolzer). The appearance looks very much like a "nonchalantly written number 2" (very thin looking, especially when the effect has just started). Discovered by Danny Caes on may the 12th, 2008 (Orion SkyQuest XT8).
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8 The curious 8 shaped (or Peanut shaped) craterlet west-northwest of Nielsen. This 8 shaped feature is described and depicted in NASA SP-362 Apollo Over the Moon, Chapter 4: The Maria (Part 3), Figure 89. Note: the photo-number which is mentioned below the depicted photograph (in AOTM) should be 10344, and not "0344"! This 8 (or Peanut) is also noticeable near the upper right corner of Lunar Orbiter 4's Frame 163-H1.
  • 9
  • 0

The 24 letters from the Greek alphabet

  • Alpha
  • Beta
  • Gamma
  • Delta
  • Epsilon
  • Zeta
  • Eta
  • Theta
  • Iota
  • Kappa
  • Lambda
  • Mu Montes Riphaeus (by Bachmann1).
  • Nu
  • Xi
  • Omicron
  • Pi The Pi symbol: the curious Pi shaped system of rilles at 18° North/ 2° East, in Sinus Fidei, slightly south of Rima Conon (by Stephan Lammel).
  • Rho
  • Sigma
  • Tau
  • Upsilon
  • Phi The Phi symbol, which is seen in Mare Serenitatis on many of the ancient lunar maps. The Bessel ray is the central "bar" of the Phi.
  • Chi
  • Psi
  • Omega

Question Mark

  • ? The Question Mark shaped formation at (roughly) 28° East/ 5° North, in Mare Tranquillitatis. This is a typical Full Moon feature, and is (or seems to be) composed of tiny high-albedo craterlets and a long thin depression, arranged as a chain in the shape of a Question Mark (or hook). It is detectable on LAC 60 (page 120) in B.Bussey's and P.Spudis's Clementine Atlas of the Moon, at the above mentioned coordinates. See also Apollo 10's Hasselblad AS10-31-4600.