Ray Craters

(glossary entry)

Description

Originally a list of craters with prominent 'ray' systems, this seems now to include bright craters with or without rays. This is far from a complete list! Please add other craters with rays. Thanks!

List of Ray Craters and bright (high albedo) spots

Many nearside descriptions are from Elger, 1895, but his east and west have been reversed to match the modern convention.
farside craters in italics

A

- Abulfeda E - A bright crater WSW of Abulfeda A. In ALPO list of bright ray craters.
- Aratus - A very conspicuously brilliant crater in the Apennines, with a smaller light-surrounded crater W. of it.
- Agrippa - Exhibits faint rays.
- Alfraganus - A light-surrounded crater with rays.
- Almanon - About midway between this and Argelander is a very brilliant little crater.
- Alpetragius B - A conspicuous light-surrounded crater, one of the most remarkable on the moon.
- Alpetragius D - (11°W 13° 8'S) A bright spot, seen by Mädler as a crater, but which as Schmidt found in 1868, no longer answers to this description.
- Anaxagoras - The centre of an important ray-system. Listed by Elger as a principal ray-system. It is also on the ALPO list of bright ray craters.
- Apollonius - Among the hills S. of this, there is a small bright streak system.
- Aristarchus - Known as the brightest crater on the entire moon's surface. Easily observable in Earthshine. A most curious fact is the antipodal location of one of the darkest craters on the moon: Tsiolkowsky! Elger listed as principal ray-system.
- Aristillus - The centre of a noteworthy system of delicate rays extending E. toward the Caucasus; and on the S. disappearing among the rays of Autolycus. They are tracable on the eastern part of Mare Imbrium near Kirch. Elger listed as a minor ray system.
- Aristoteles A - A light-surrounded crater in the Mare Frigoris, N.W. of Aristoteles.
- Atlas (bright spot east of) (unofficially called Atlas Companion by William Dembowski) (see LROC article Brush Strokes on a Lunar Canvas).
- Autolycus - Encircled by a delicate nimbus, throwing out four or five prominent rays extending toward Archimedes. Seen best under evening illumination. Elger listed as minor ray system.

B

- Baby Ray - A very small ray-craterlet near North Ray and South Ray (see: Additional Information, below).
  - Bailly - N. of the centre of this great enclosure are two very distinct radiating streaks.
  - Banting - unnamed craterlet with 3/4's ejecta blanket southeast of Banting. See orbital Apollo photograph.
  - Beaumont - Between this and Cyrillus stand three considerable craters with nimbi.
  - Bessarion - Two bright craters: the more northerly is prominently light-surrounded while its companion is less conspicuously so.
  - Birt A - A light-surrounded crater.
  - Blackett-Brouwer (small white spot between Blackett and Brouwer, LAC 122 in the Clementine Atlas). Looks like an oblique impact on the LRO's ACT-REACT Quick Map. There's a pile of low albedo rocks and boulders at the northwestern part of the craterlet's interior, and smooth-looking high albedo streamers on the southeastern inner slopes. Magnificent raycraterlet! - DannyCaes Jun 6, 2011
  - Bok (north-northeast of).
  - Briggs B - SW of Lichtenberg. In ALPO list of bright ray craters.
  - Buch B - A very small "compact" bright spot with somewhat dark nimbus (38° south/ 17° east).
  - Byrgius A (H.P. Wilkins's La Paz). Elger listed as principal ray-system.

C

- Cassini's Bright Spot (see also: Hell Q).
  - Cavalerius - A light streak originating in the E. wall, and extending on to the Oceanus Procellarum.
  - Censorinus - A very brilliant crater with faint rays.
  - Chappy - The small ray-craterlet on the northeastern part of Chaplygin's rim. This craterlet is unofficially called Chappy by Mark Robinson (LROC).
  - Chevallier - Very bright oblique impact ray craterlet just northwest of Chevallier. This is the same craterlet which is nicknamed Atlas Companion by Bill Dembowski (see at Atlas above).
  - Cleomedes A - (On the floor.) Surrounded by a nimbus and rays. Large crater A, on the W. has also a nimbus and rays.
  - Coblentz (east-southeast of).
  - Copernicus - The "Monarch" of the moon. The most observed and photographed crater on the moon's Near Side. Elger listed as principal ray-system.
  - Bright ray-craterlet immediately west of Copernicus, see LPOD A New Crater?
  - Crookes
  - Cyrillus A - A prominent light-surrounded crater.

D

- Daguerre (small craterlet with 3/4 ejectablanket on the floor of Daguerre, see orbital Apollo 16 photograph).
  - Damoiseau - A light-surrounded crater E. of Damoiseau, (58° W, 6°S).
  - Darney - North of Lubiniezky. In ALPO list of bright ray craters.
  - Darney C - West of Darney. In ALPO list of bright ray craters.
  - Darwin C - High-Albedo craterlet on the rim of Darwin C.
  - Delisle - South of this formation there is a tolerably bright spot on the site of some hills.
  - Denning V (immediately west of). A raycrater with excluded zone resulting from angled impact. Denning V lies within excluded zone. See AS08-13-2328. Research David Woods and Frank O'Brien (Apollo 8 Flight Journal).
  - Dionysius - famous as a dark ray crater. See LPOD March 17th, 2009 (Mario Weigand's Hi-Res photo of Dionysius).

E

- Eimmart - There is a large white spot N.E. of this.
  - Einstein/Balboa (bright spot between Einstein and Balboa).
  - Encke X - has a rare dark ray northwest of it (see LO-3's Frame 161; the lower right part of the -Med- photograph).
  - Erro/Saenger (between Erro and Saenger). A series of orbital photographs of this bright raycrater was made during Apollo 16, of which AS16-121-19418 is one example. Note the two dark "rays" running northwestward of the bright craterlet itself. These two dark "rays" are also noticeable on LAC 64 (page 128) of the Clementine Atlas of the Moon. Research: Danny Caes.
  - Euclides - Has a conspicuous nimbus with traces of rays, a typical example.
  - Eudoxus A - A light-surrounded crater E. of Eudoxus, with distinct long streaks, one of which extends to the S. wall of Aristoteles.
  - Euler - Feeble halo with streaks.

F

- Fechner T
  - Feoktistov (east of).
  - Finsen/Maksutov (between Finsen and Maksutov).
  - Flamsteed C - A light-surrounded crater on a dark surface.
  - Furnerius A with Stevinus A, which form the bright area south of Petavius. Elger listed it as a minor system. This bright pair is sometimes called The Headlights.

G

- Galilaei - Between this and Reiner is a curious bright formation with short rays.
  - Galvani B (small oblique impact raycrater on the western part of Galvani B's rim and inner slopes).- DannyCaes Oct 29, 2011
  - Gambart A - A bright crater with large nimbus and rays.
  - Gassendi Bright Spot - A bright spot located east of Gassendi G and NW of Gassendi itself. It was mentioned in the Aug 15th 2008 LPOD. Note: on Chart 51 of Antonin Rukl's Atlas Of The Moon it is depicted as a small white lozenge-shaped rectangle.- DannyCaes Aug 15, 2008
  - Geminus - associated with a system of very delicate rays.
  - Gibbs (a very bright spot on the northeastern part of Gibbs's rim).
  - Giordano Bruno - Could be one of the most recently formed craters in the long history of Earth's satellite!
  - Glushko - (formerly known as Olbers A). The ALPO list of bright ray craters lists this ray crater as Olbers D. Elger listed as principal ray-system.
  - Godin - Exhibits faint rays.
  - Goodacre P (small ray-craterlet immediately east-northeast of Goodacre P, interior looks very chaotic on the LRO's close up).
  - Grimaldi - There are three bright spots on the E. wall.
  - Guericke - There is a crater, with nimbus, E. of this, in 12°W, 11°5'S.

H

- Hainzel - There are several bright spots W. of this formation.
  - Harpalus - a faint ray system.
  - Hawke - On the southern part of Grotrian's rim (this raycrater received the official name Hawke in 2018).
  - Hayford (bright spot north-northwest of).
  - Hayford/Krasovskiy (small bright spot between Hayford and Krasovskiy).
  - Hayn source of ray segment going through Geminus C
  - Hell - A large ill-defined spot in 4°W, 33°S. This is most probably the site of the white cloud seen by Cassini. See Hell Q (Cassini's Bright Spot).
  - Hypatia B - A very small bright crater on a dark surface: surrounded by a faint nimbus.

I

- Innes G (immediately east of Innes G).
  - Isaev (west of). See: AS08-13-2327 or AS08-13-2327 High Resolution scan , and Figure 98 of *NASA-SP362 Apollo over the Moon* Research Danny Caes.

J

- Jackson- Together with Ohm, Jackson is one of the largest ray craters on the moon's Far Side.
  - Joule T

K

- Kearons (southwest of).
  - Kepler - Elger listed as principal ray-system.
  - Koch/Pauli (between Koch and Pauli).
  - Koval'skiy Y (on the southern part of Koval'skiy Y's rim). This is probably an oblique impact crater. Looks like a broad white spot on the photographic version of LAC 100 (page 200) in the Clementine Atlas.
  - Kurchatov (south-southeast of).

L

- La Condamine S - Visible in the upper half of photograph LO IV-145-H3 in a curious field of twisted bay- and arc-shaped remains of small craters in Mare Frigoris, north of La Condamine. - DannyCaes Nov 16, 2008
  - La Pérouse A - A very bright spot! (see Apollo 15's orbital close-ups: AS15-81-10906, AS15-81-10907, and AS15-81-10922).
  - Lacroix B - (northwest of Lacroix).
  - Langrenus - Has a large but very pale ray-system. It is best seen under a low evening sun. Three long streaks radiate towards the W. from the foot of the glacis of the S.W. wall.
  - Langrenus M - Mentioned in LPOD as having a dark ray.
  - Lalande - Has a large nimbus and distinct rays.
  - Lansberg - West of Lansberg, four light-surrounded craters, forming with Lansberg A an interesting group.
  - Lansberg A - A light-surrounded crater on a dark surface, with companions, referred to under the Third Quadrant.
  - Lassell D - A very bright spot, of the same kind as Werner D, Linné, and Posidonius Gamma.
  - Leakey - A very bright high albedo ray-craterlet north-northwest of Leakey, see also LPOD Swept Away.
  - Legendre H - A bright spot SW of Humboldt.
  - Lichtenberg - Faintly light-surrounded.
  - Lichtenberg B
  - Littrow - A very bright light-spot with streaks, on the site of a little crater and well-know cleft W. of this ring-plain.
  - Lohrmann A - A light surrounded crater, with a light area a few miles N. of it. 1°S, 61°W.
  - Louise - North of Diophantus and south of Delisle. In ALPO list of bright ray craters.
  - Lubiniezky A, F, and G - Crater with halo on a dark surface.

M

- Macrobius - Two light-surrounded craters on the W. of this formation, the more northerly being the brighter.
  - Mädler - This ring-plain and the neighbourhood on the N. and N.E., include many bright areas and curious streaks.
  - Mandel'shtam G (just north of it).
  - Manilius - Surrounded by a light halo and streaks.
  - Mare Crisium North Rim - A very bright 1.5 km ray craterlet at 22.69°N, 54.45°E.
  - Mare Moscoviense (bright raycrater just outside the north-northwestern part of Mare Moscoviense's rim).
  - Mare Smythii North Rim - A tiny bright star-shaped ray craterlet at 3°55' N, 88°50' E (see also at Additional Information below).
  - Mechnikov (south-southwest of).
  - Mee (small bright spot on floor of Mee).
  - Meggers (north of).
  - Menelaus - A brilliant object. It is traversed by a long ray from Tycho. Listed by Elger as a minor ray system.
  - Mercator - There is a brilliant crater and light area under W. wall.
  - Mersenius - Two or three light-rays originate from a point on the E. rampart.
  - Mersenius C - A light-surrounded crater with short rays.
  - Meshcherskiy (northeast of).
  - Messier A - The well-known "Comet" rays, extending W. of this.
  - Moore F
  - Mösting C - A light-surrounded crater.

N

- Neander (west of).
  - Necho (once nicknamed "The Bright One" and also called "Roosa" by NASA and the crew of Apollo 14)(A14's CMP Stuart "Stu" Roosa).
  - North Ray - (see: Additional Information, below).

O

- Ohm - Together with Jackson, Ohm is one of the largest ray craters on the moon's Far Side.
  - Olcott (southeast of). An oblique impact raycrater, worthwile to explore its peculiar albedo-differences on the LRO's Hi-Res photographs at the ACT-REACT Quick Map.

P

- Parry - A very brilliant light-spot in the S. wall.
  - Parry A - Surrounded by a bright nimbus. The IAU name is Tolansky.
  - Pavlov-Jules Verne raycrater - an unnamed bright ray crater between Pavlov G and Jules Verne Y. Its rays are similar to Proclus on a smaller scale.
  - Peirescius A - a bright craterlet at 45.2°S/71.3°E between Peirescius and the dark floor of Oken, observed by - AndrewMartinSFO.
  - Petavius B (H.P. Wilkins's "Orus").
  - Petit - A very bright spot!
  - Pierazzo - This is the most beautiful ray-craterlet on the moon! (near crater Lentz, slightly "behind" the Full Moon's western limbus). This craterlet shows an exceptionally well developed nimbus of rays! (see also Additional Information below).
  - Plato M - this bright craterlet's ejectablanket shows a remarkably light-bluish coloration when it is observed during Full Moon.- DannyCaes Jun 28, 2008
  - Plinius A - Is surrounded by a well-marked halo.
  - Posidonius Gamma - Among the hills W. of this formation a light spot resembling Linné, according to Schmidt. He first saw it in 1857, when it had a delicate black spot in the centre. Dr. Vogel observed and drew it in 1871 with the great refractor at Bothkamp. These observations were confirmed by Schmidt in 1875 with the 14-feet refractor at Berlin.
  - Proclus - A well-known ray-centre, some of the rays prominent on part of the Mare Crisium. Elger listed a minor ray system.

Q

R

- Reimarus H - A bright craterlet S.E. of the southern section of Vallis Rheita and N. of Brisbane H.
  - Römer - A light-surrounded mountain on the W.
  - Romer R - small bright raycrater slightly west of Romer R.
  - Ryder - very bright crater east of Pauli and Roche (between Pauli and Koch).

S

- Schickard - Four conspicuous light spots, probably craters, on the S.W.
  - Schubert/Back (a small bright raycraterlet west of the Schubert-Back pair).
  - Soddy (a curious ray-craterlet with bright and dark spots on its interior and bright/dark streaks in its ejectablanket, immediately north of Soddy and Hero H).
  - South Ray - (see: Additional Information, below).
  - Stefan L
  - Stevinus A with Furnerius A, which form the bright area south of Petavius. This pair of high-albedo raycraters is sometimes called The Headlights.
  - Sinus Honoris's northwestern end (a bright spot between Julius Caesar and Menelaus, see: Additional Information, below).
  - Sulpicius Gallus - A light spot near.

T

- Tacitus - unnamed crater between Tacitus H and Tacitus A.
  - Tacquet - Has a prominent nimbus and indications of very delicate streaks.
  - Taruntius - Has a very faint nimbus, with rays, on a dark surface.
  - Thales possible source of ray segement going southward to Mason-Plana.
  - Theaetetus - A very brilliant group of little hills W. of this formation.
  - Theophilus - The central mountain is faintly light-surrounded.
  - Timaeus - A ray-centre.
  - Timocharis - Is surrounded by a pale irregular nimbus and faint rays, most prominently developed on the E. side of the formation. Listed by Elger as a minor ray system.
  - Tycho - One of the most well-known ray craters on the moon's surface. Visible to the unaided eye during Full Moon! Elger listed as principal ray-system.

U

V

- Ventris M
  - Virtanen

W

- Werner D - A very bright spot, of the same kind as Lassell D, Linné, and Posidonius Gamma.

X

Y

Z

- Zernike W (white spot in Zernike W).
  - Zhukovskiy (west of).
  - Zucchius - A remarkable ray-system, but one which is only well seen when libration is favourable. Listed by Elger as a principal ray-system.

Additional Information

North Ray and South Ray
During the last year of the Apollo program, the fifth manned lunar landing (Apollo 16's LM Orion, April 1972) took place near a couple of small bright ray-craterlets called North Ray and South Ray (north of Descartes and Dollond). Of these two, South Ray is the brighter one. The southeastern part of the North Ray's rim is the location of the so-called Big Black Boulder (House Rock), which was the largest piece of rock explored by astronauts on the moon's surface. These two small ray-craterlets are observable through common telescopes, during Full Moon. Research: Danny Caes
- A very small ray-craterlet near South Ray has been called "Baby Ray". Perhaps it is also possible to make Hi-Res webcam images of that tiny raycrater (?).

The most beautiful lunar ray-crater
Since 2015 officially known as Pierazzo, located at 3° North/ 100° West, near crater Lents. Unfortunately its location is a bit too westward "behind" the moon's western limb ("behind" Hedin). A little bit more eastward and its ray system could have been one of the most interesting targets for telescopic lunar observers! The extraordinary ray system around this crater was captured during the Clementine mission in 1994 and the Chang'e-1 mission in 2007. See also LAC 72 in Ben Bussey's and Paul Spudis's Clementine Atlas of the Moon, and the LPOD of December 12th, 2007 (the Chang'e-1 photograph of this raycrater). Research: Danny Caes

A tiny bright spot on the moon's near side
One of the most "compact" or "starlike" areas with unusually high albedo-value is located at 13° North/ 16° East, between Menelaus and Julius Caesar (the northwestern end of Sinus Honoris). The curious bright "starlike" appearance of this ray-craterlet is a noteworthy curiosum during telescopic observations of the Full Moon. One of the few orbital Hasselblad photographs of it is AS15-92-12548, made during the mission of Apollo 15 in the summer of 1971. Another orbital Hasselblad is AS15-93-12678, which is the only close-up of it on color film! Research: Danny Caes

Mare Smythii's bright starlike spot
Located at 4° North/ 89° East (between craters Peek and Nunn at the northern rim of Mare Smythii) is another curious bright spot with the typical shape of a "star". This star-shaped bright spot (a tiny raycrater) was photographed during the missions of Apollo 10, 11, 15, and 17 (orbital Hasselblad and Itek photography). It would be interesting to try to observe this bright spot, and to make Hi-Res photographs of it during favourable libration at the moon's eastern limb. Research: Danny Caes

Orbital Apollo photographs of the bright star-shaped ray craterlet at the northern rim of Mare Smythii (see also LAC 63 (page 126) in the Clementine Atlas of the Moon)
AS10-33-4886
AS10-34-5081 (color photograph, the bright craterlet's location is near the frame's left margin)
AS11-42-6295 (vertical close up)
AS11-42-6296 (vertical close up, a bit brighter than 6295)
AS11-43-6452 (vertical close up)
AS15-P-9108 (scroll toward the bright craterlet's location a little bit beyond the centre of this horizontal bar-shaped photograph)
AS17-P-2573
AS17-P-2578
AS17-P-2580
Research: Danny Caes

Mare Vaporum's tiny starlike spot
Located at 14°30' North/ 0°15' West (at the western "shoreline" of Mare Vaporum) is a very tiny bright "spot" which is noticeable near the upper margin of LAC 59 (page 118) of B.Bussey's and P.Spudis's Clementine Atlas. This spot is observable through common and powerful telescopes, during Full Moon. Research: Danny Caes

Three of Apollo 15's orbital close-up Hasselblad photographs of the area near Dorsum Gast (the western part of Mare Serenitatis) show a remarkable bright craterlet with unexpected dark "tongue" of ejected material at the southwestern rim of it, located at the southern end of that dorsum (Dorsum Gast). The exact coordinates of that curious craterlet are: 23° North/ 8°40' East.
The three Hasselblad close-ups of that curious craterlet:
AS15-81-10876
AS15-81-10881
AS15-81-10883
Research: Danny Caes

The Chandrayaan-1 spacecraft captured an interesting example of what appears to be a fresh rayed crater on the floor of a larger crater. It is included in their photo gallery, but the location of the feature is not disclosed.

Description: Wikipedia

Wikipedia

LPOD Articles

Radiant Rays, Ray Systems, Another one from the LPOD gallery (Dionysius), Rayology (the high-albedo raycraterlets near Stevinus)

Bibliography

Ray Systems, Chuck Wood's Moon Web site.
Apollo Over The Moon; a view from orbit (NASA SP-362), Chapter 5: Craters.
Grier, Jennifer A. et al. 2001. Optical maturity of ejecta from large rayed lunar craters. Journal of Geophysical Research, Volume 106, Issue E12, p. 32847-32862.
Hackman, Robert J. and Army Map Service. 1960/1961. Engineering Special Studies of the Surface of the Moon: Lunar Rays. Map I-351 (depicts ray systems visible from Earth).
Hawke, B. Ray et al. 2004. The origin of lunar crater rays. Icarus, Volume 170, p. 1-16.
Pieters, C. M. et al. 1985. The Nature of Crater Rays' The Copernicus Example (PDF). Journal of Geophysical Research, Vol. 90, No. B14, pp. 12,393-12,413

See also the ALPO list of bright ray craters.

Ray craters

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