Colored regions

Colored regions on the moon's surface (Part 1)

(glossary entry)
 
 
 An exploration of the moon's subtle colors, by Danny Caes
 
 Part 1 is an overview of telescopic (and orbital) observations/photographs of the moon's subtle colors, by dedicated moon-observers and by all 24 Apollo astronauts, of which the Command Module Pilots made very interesting descriptions of curious local colorations!
 Part 2 is a rather curious look at the moon's colors, and rare thoughts/hypotheses (the possible cause of the red-colored Transient Lunar Phenomena, TLP). It is also an enthusiast's exploration of the visual perception of colors.
 Part 3 is an exploration of subtle colors on lunar boulders, rocks, and regolith. All photographs by the Apollo astronauts and previous unmanned landers.
 
 Don Davis' color-calibration chart
 
 

Description

To most occasional lunar observers, the moon's surface looks just light grey, or somewhat yellowish light grey (a.k.a. "Greige": a mixture of Grey and Beige). Experienced observers of the moon however know several locations of subtle colors and hues. These colorations are not immediately detectable, most of them show nothing more than weak "shifts" of grey (somewhat blue-ish, or somewhat yellow-ish/ orange-ish).
  Full Moon observer Danny Caes described the subtle colorations of the moon's surface as follows:
  "Take a bucket of grey paint and add a spoon of Vermilion red pigment powder and another spoon of Citron yellow pigment powder, mix very well, and the result looks like the color of Mare Serenitatis", and... "Take another bucket of the same grey paint, add a spoon of Sky blue (or Steel blue) pigment powder to it, and it looks like the color of Mare Tranquillitatis", and... "compare both buckets, and you shall see that there's noticeable contrast, just like the telescopic view of the borderline between Mare Serenitatis and Mare Tranquillitatis" (note that, when one of the two buckets of altered grey paint is investigated "on its own", it shall look just... "grey").
 
 

Wood's Spot, Lassell Massif, Ina, Langrenus, Beaumont L, Young, Maginus, ...

Some areas on the moon's surface don't require a color-sensitive observer's eye, such as the remarkable "mustard"-colored Wood's Spot near Aristarchus and Herodotus (also called the Aristarchus Plateau). This is probably the most colored region on the entire moon's surface.
  A very interesting little region is the somewhat tan-colored Lassell Massif, which was investigated and described by the Command Module Pilot of Apollo 16 (Ken Mattingly):
  "I'm looking at Lassell C and the little highlands clump that's by it. And - remember, we had a red and a blue color difference, and right now the Southern Pease with a crater in it is sort of a - a tan color, and the Northern Pease is a gray. When I look at the mare, I see a big swatch of - of the tan-colored mare down to the south that goes over towards Guericke. And I see a - a tongue of darker gray material. The area around Lassell C has the tan tone to it. Then it goes out about as far as our little cone and the little bright crater next to it. That's about the outer limit - maybe just a little beyond. Then there's a patch of the - of this tan stuff that's down to the south that about lines up with the big Achaean rille that's over to the southeast. Then there's a patch in the gray-colored mare down inside of that. It's just a little circular piece. In looking at the Lassell C feature - a look at it in detail - it appears to me that this tan stuff on the south end of it has fewer craters than the stuff on the north, although not an awful lot, but there's little pitted craters all over the northern part. They're not on the southern parts and there are a couple of light, streaked bands that appear in the southern clump that you don't see in the north".
  (Apollo 16 Flight Journal, David Woods, Tim Brandt).
  See also the LROC article Color of the Lassell Massif.
 
  During the missions of Apollo 15 and Apollo 17, a peculiar light-blue coloration was observed at the D-shaped depression called Ina, in Lacus Felicitatis. One of the orbital Hasselblad photographs made during Apollo 17 shows an oblique view of Lacus Felicitatis with Ina on it (AS17-151-23259). Ina is just below left of centre. The Print-Resolution JPG; 5 MB shows the weird coloration of Ina.
 
  The crew of Apollo 17 noticed remarkable orange-ish and dirty brick-red colored spots near and on the "small lakes" west of Montes Haemus, and also near Sulpicius Gallus (see Apollo 17 Preliminary Science Report), and indeed, a telescopic view of this region (during Full Moon) reveals a somewhat dirty reddish-tannish hue up there. See also: Sulpicius Gallus Formation: a splash of color (ASU's Apollo Image Archive, Image of the Week).
 
 

Two partially reddish-brown colored ray craterlets north-northeast of Bowen (west-southwest of Sulpicius Gallus)

In december 1972 both of these partially reddish-brown colored ray craterlets were captured on two of Apollo 17's orbital Hasselblad photographs of the Bowen-Sulpicius Gallus region at Montes Haemus. The two Hasselblad frames are AS17-152-23284 and 23285 (High-Resolution scans from Kipp Teague's Apollo photogalleries on Flickr) (online since october 2015).
  The pinpoint coordinates of these two ray craterlets are; The larger (eastern) one: LAT 18.9393/ LON 9.8642, the smaller (western) one: LAT 18.8511/ LON 9.6124. (see the LROC's online ACT-REACT QUICK MAP).
  Research: Danny Caes
 
  The crew of Apollo 14 noticed orange- or reddish ("rusty") colored spots on the inner slopes and floor of Langrenus, and also at craterlet Beaumont L (see Apollo 14 Preliminary Science Report).
 
  In Harold Hill's book A Portfolio of Lunar Drawings, page 234, there's a description of crater Young's greenish hue: "A number of observers have claimed in the past that the inner slopes of the formation Young have a greenish, almost translucent cast or sheen when seen at the evening terminator".
 
  In V.A.Firsoff's book The Old Moon and the New, page 193, there's a description of crater Maginus' greenish colored southern slopes: "Some observers have reported Vivid Greens, mostly in the maria seen at small phase, but also, for instance, on the southern slopes of Maginus and near the Rheita Valley".
 
  Walter Goodacre observed, near local sunset at Atlas, a light brown shade extending from the crest of Atlas' wall halfway across the floor (see T.W.Webb's Celestial Objects for Common Telescopes, Volume 1: The Solar System, page 160).
 
  Elger observed a peculiar coloration when the evening terminator was near Geminus:
 "On several occasions, when observing this formation and the vicinity, I have been struck by its peculiar colour under a low evening sun. At this time the whole region appears to be of a warm light brown or sepia tone".
 
  The surroundings of craterlet Torricelli B show some sort of steel-blue/grey coloration when it is observed during Full Moon.
 
 

Color effect near Lichtenberg

The Lichtenberg crater - a relatively small isolated ring 12 miles in diameter - is a celebrated object because it was here between the years 1830 and 1840 that Madler observed a strong reddish tint closely east of the crater. No one appears to have seen this subsequently until its recovery in 1940 by Barcroft in the USA when it was described as 'a pronounced reddish-brown'. Haas, at a later date, observed the same effect and in 1951 Baum in the UK reported a rose-pink coloration which persisted for a time and then faded.
  Between 0115 and 0320 on April 1 1988 (no significance in the date!) the author saw, for the first time in his experience, rosy-tinged areas fringing the northern edge of the lava sheet. The moon had hitherto always looked quite neutral in colour to his eyes but the effect on April 1 was unmistakeable and certainly not due to atmospheric dispersion or other false effects, because a most careful check was made with bright objects, such as Lavoisier A. The telescope employed was a 10" reflector using various eyepieces as a safeguard, but the colour persisted until weather conditions deteriorated. The area has been described as 'red sensitive' but, if so, it is curious that the coloration is rarely in evidence, even when specially looked for under the most suitable conditions. There the matter must rest....at least for now.
 - Harold Hill, A Portfolio of Lunar Drawings, page 94.
 
 

Color effect at Aristarchus and Vallis Schroteri's Cobra Head

"Early in the evening of October 29, 1963, Mr. Edward Barr and I had started our regular lunar observations... When I started to observe at 1830 MST I concerntrated on the Cobra Head of Schroeter's Valley... at 1850 MST I noticed a reddish-orange color over the dome-like structure on the southwest side of the Cobra Head. Almost simultaneously I observed a small spot of the same color on a hilltop across the valley. Within two minutes these colors had become quite brilliant and had considerable sparkle. I immediately called Mr. Barr to share this observation with me. His first impression of the color was a dark orange. No other color spots were noted until 1855 MST when I observed an elongated streaked pink color along the southwest rim of Aristarchus...at approximately 1900 MST I noticed the spots of color at the Cobra Head and on the hill across the valley had changed to a light ruby red...I had the impression that I was looking into a large polished gem ruby but could not see through it. Mr. Barr's impression of the color at this time was that a little more dense than I had described it... By 1905 MST it was apprent that the color was fading".
 - Taking Science to the Moon- Lunar Experiments and the Apollo Program, by Donald A. Beattie, chapter 2, p. 25
  Transcript quote by James Greenacre, employed at the time by th US Air Force Lunar Mapping Program at the Lowell Observatory.
  Thanks Andrew Martin SFO !- DannyCaes Aug 13, 2008
 
 

Humanity's first orbital lunar observations - the crew of Apollo 8, december 1968

069:51:04 Gerald Carr (CapCom): "Apollo 8, Houston. What does the ole Moon look like from 60 miles? Over". (Pause)
069:51:16 James Lovell: "Okay, Houston. The Moon is essentially grey, no color; looks like plaster of Paris or sort of a grayish beach sand. We can see quite a bit of detail. The Sea of Fertility doesn't stand out as well here as it does back on Earth. There's not as much contrast between that and the surrounding craters. (Pause) The craters are all rounded off. There's quite a few of them, some of them are newer. Many of them look like - especially the round ones - look like hit by meteorites or projectiles of some sort. (Pause) Langrenus is quite a huge crater; it's got a central cone to it. (Long pause) The walls of the crater are terraced, about six or seven different terraces on the way down" (Long pause).

(Jim's impressions of what he sees have been replayed many times on documentary films of the Apollo program, especially his first sentence. Though his words are honest, they predate NASA's emphasis on science and geology that led to later commanders, Jim included, becoming accomplished field geologists themselves and enthusiasts of what the Moon's landscape has to offer. Perhaps as a consequence, his portrayal of the lunar surface as grey and colourless set a tone for the public's subsequent perception of the Moon as uninteresting).
- Apollo 8 Flight Journal, David Woods and Frank O'Brien.

The remarkable green-blue colored orbital photographs of Apollo 8

This strange effect is noticeable in almost all of the Apollo-related spaceflight books: the curious greenish-bluish coloration of Apollo 8's orbital lunar photographs.
  One such book is Herbert J. Pichler's Die Mondlandung, der menschheit grosstes abenteuer (1970), pages 276-277 (AS8-14-2447 and AS8-14-2399) (perhaps there was not enough Magenta ink when these two frames were printed...) (there's too much Cyan and Yellow in them, the result: Green!).
  Although heavily processed, the LPI's online scans (of Apollo 8's Magazine 14 / B) also show very well this curious greenish-bluish cast!
  See also:
 Apollo Photography and the Color of the Moon (Michael Light and Eric M. Jones).
  And:
 - V.A.Firsoff's The Old Moon and the New (Sidgwick & Jackson, London 1969).
 
 

The moon's warm brown chocolate hue

The orbiting Apollo astronauts noticed a peculiar phenomenon when they observed the lunar surface at a small angle related to the sun's light. At such small angle, the lunar surface appeared warm brown colored. Photographs of brown colored lunar surface were printed in the article To The Mountains of the Moon (Apollo 15 explores the mountains of the moon) by Kenneth F. Weaver, in the National Geographic of February 1972.
  Don Davis created an interesting colored version of one of Lunar Orbiter 1's B-and-W photographs of the bluish crescent Earth and brown colored "chocolate-looking" lunar landscape.
  I wonder if this phenomenon (the moon's warm brown hue) is also noticeable when the crescent moon is observed through telescopes? (moon-to-sun's small angle related to the sun's light).- DannyCaes Aug 3, 2008
 
 

LPOD Articles

Color Moon Map by Filipe Alves
Magical Bi-Color Moon (remarkable false-color image of the moon's near side, Filipe Alves).
Outrageous Lunar Colors (Waxing Gibbous near Full Moon, Filipe Alves).
Bi-Colored Moon (Last Quarter Moon, Filipe Alves).
Beyond Red (Waning Gibbous Moon, Nordic Optical Telescope).
A Celestron Orange Moon (Waning Gibbous, Bareket Observatory, Israel).
Blue Moon (Waxing Gibbous Moon, Tom Bash).
Colorful Aristarchus Plateau (Tom Williamson).
Aristarchian Colors (Mikhail Abgarian, Yuri Goryachko, Konstantin Morozov).
What? More Tycho? (Mikhail Abgarian, Yuri Goryachko, Konstantin Morozov).
Compelling Copernican Color (Mikhail Abgarian, Yuri Goryachko, Konstantin Morozov).
Copernicus in Color (Lunar Orbiter IV and Clementine orbiter).
Colorful Privolva (the moon's far side, called Privolva by Johannes Kepler, Clementine orbiter).
Digging Below the Surface (Triesnecker and environs, Clementine orbiter/ Map-A-Planet).
An Increasingly Complex Tale (Rumker, Clementine orbiter/ Map-A-Planet).
Galileo's Colorful Moon (see also APOD's -The Colorful Moon-, below).
Iranian Moons (Full Moon by Shahriar Davoodian, and First Quarter Moon by Mohammad Shirani).
New Color in Old Pictures (orbital Apollo-Hasselblad AS15-87-11703: Carmichael + Hill, enhanced by Stefan Lammel).
Four Moons (Waning Gibbous/ Waxing Gibbous/ Partial Lunar Eclipse/ Waxing Crescent + "Ashen Light", Alan C. Tough).
Brown Flows (Mare Imbrium and Sinus Iridum, Fabrice Morin).
Partial Phase of Pinkness (the cratered region southeast of the Ptolemaeus group, Dominique Dierick).
SW Taper (the southwestern part of the Waning Crescent Moon, with curious "Lapis Lazuli"-colored crater rims, Dominique Dierick).
Streaks across a Mauve Moon (the Full Moon "tilted upward", to have a good look at the southern cratered hemisphere, Zac Pujic).
A Colorful Helmet (Zac Pujic's enhanced colors of The Helmet, east of Gassendi and Andreus Hills).
A Green Flow on a Green Sea (Zac Pujic's enhanced colors of the Carlini - McDonald region in Mare Imbrium).
Chocolate Maria (Markov and the Telemann Formation, Zac Pujic).
Was Anaxagoras an Oblique Impact? (Zac Pujic and Mario Weigand).
Black & White & Color All Over (Milton Aupperle's two views of the Waxing Gibbous Moon).
A Colorful Bay! (Sinus Iridum and Mare Imbrium, John McConnell).
Colorful Friday (Mare Serenitatis, John McConnell).
Color on the Cheap (Mare Tranquillitatis, John McConnell and Clementine/ Map-A-Planet).
Red Arrowhead (Mons Hansteen, Rick Evans).
Ochre Patches (the Tycho-Clavius-Longomontanus region by Michael Hunnekuhl).
Spotted Moon (the Mare Nubium region by Michael Hunnekuhl).
Tough Moon (Waning Gibbous Moon, by Alan C. Tough).
Which Way is Up? (three Full Moons: one "normal", one "upside down", and one "mirror image", Mario Weigand).
Colorless Colors (Ewen A. Whitaker's remarkable photograph of "rare" Full Moon).
Chasing Cryptomaria (the southwestern part of Dmitry Makolkin's superb King-Size mosaic of the colorful Waning Gibbous Moon).

LROC Articles

Color of the Moon
Color of the Lassell Massif

APOD Articles

Colorful Moon Mosaic (Waxing Gibbous Moon, Noel Carboni).
The Color of the Moon (Waxing Gibbous Moon, Johannes Schedler).
The Mineral Moon (North Pole View, Galileo interplanetary spacecraft).
The Colorful Moon (Full Moon, Galileo interplanetary spacecraft).
Strange Orange Soil on the Moon (Apollo 17's discovery of the orange regolith at Station 4's rocky outcrop near Shorty crater).

Others (photographs of the moon's colors)

Astronominsk - colorful Full Moon
David Woods - Waxing Gibbous Moon
David Woods - Waning Gibbous Moon
Russell Croman - The Colors of the Moon (Waxing Gibbous Moon).
Russell Croman - The Aristarchus Plateau (Wood's Spot).
Dominique Dierick - Waxing Gibbous Moon
Dominique Dierick - Waning Crescent Moon
Dominique Dierick - Aristarchus Plateau and environs
Dominique Dierick - Waxing Gibbous with terminator at Copernicus
Dominique Dierick - Waning Crescent and shadowed Sinus Iridum This is a remarkable photograph! It shows the opposite phenomenon of Sir Patrick Moore's Jewelled Handle Effect at Montes Jura and Sinus Iridum. Dominique's image could be a photographic version of Harold Hill's subtle drawing at page 88 of the book A Portfolio of Lunar Drawings (1991). Note the curious "Lapis Lazuli"-colored craters near the moon's south pole! See also: LPOD "SW Taper" (D.Dierick).
Peter Dove - Moon: High Saturation (Waning Gibbous Moon).

Bibliography and sites

- Alves, Filipe; How to capture the Color of the Moon
  - Aupperle, Milton; Astro-Images and Colorful Moons
  - Lecleire, Jean-Marc; Posters et Photographies Astronomiques. Wonderful posters of the moon's colors!
  - Lecleire, Jean-Marc; Blog Astronomique - Mai 2007. Interesting mooncolor experiments!
  - Morin, Fabrice; Astrosurf; colorful lunar photographs.
  - Weigand, Mario; Die Farben des Mondes, Mondfotos - Portraits (First Quarter's, Waxing Gibbous', and Full Moon's colors). Excellent photography!
  - L. Rudaux and G. De Vaucouleurs: Nouvelles Recherches Sur La Lune, with colored map of the moon. L'illustration, 19 mai 1928, page 524.
  - L. Rudaux and G. De Vaucouleurs: L'astronomie, les astres, l'univers. Larousse, Paris, 1948 (contains a small version of the same colored moonmap which appeared in the 1928's L'illustration).
  - V.A.Firsoff: The Old Moon and the New, Sidgwick & Jackson, London (1969). Note that there's lots to read about the moon's colors in this book's last chapters!
  - A.J.M.Wanders: Op Ontdekking in het Maanland (Het Spectrum, 1949). Classic descriptions of the colors on the moon.
  - K.F.Weaver: To the Mountains of the Moon (Apollo 15 explores the mountains of the moon), National Geographic, February 1972, pages 230-265 (contains a photograph of a soap-green colored piece of lunar rock; page 263, and a description of the lunar surface's "chocolate-hue", observed in orbit around the moon; page 257).
  - Register, Bridget Mintz; The Fate of the Moonrocks, ASTRONOMY December 1985, pages 14 to 22. Page 19 shows a feldspar/olivene moonrock, with gold-colored streaks on it (the olivene).
  - van den Bergh, Sidney, 1962. The color of the moon, Astronomical Journal, Vol. 67, p. 147.
  - efg's Color sites (everything on colors and the perception of them).
  - Davis, Don; Color in the Solar System The Moon (B-and-W and COLOR photography).
  - Apollo Preliminary Science Reports (NASA).
  - Kelley, Kevin W. / Association of Space Explorers (ASE) / Schweickart, Russell / Cousteau, Jacques-Yves; The Home Planet (Outer Space Photography). This book contains orbital photographs of earth (and earth's moon too), and questions about the moon's colors by the astronauts of Apollo 17.
 

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