Tag Archives: moon

An image taken in Guatemala in late 2019. Lights from small towns are visible in the foreground behind the huge Pacaya volcano. But why does Saturn appear so big? To wit:

It doesn’t — what is pictured are foreground clouds on Earth crossing in front of the Moon. The Moon shows a slight crescent phase with most of its surface visible by reflected Earthlight known as ashen glow. The Sun directly illuminates the brightly lit lunar crescent from the bottom, which means that the Sun must be below the horizon and so the image was taken before sunrise.This double take-inducing picture was captured on 2019 December 24, two days before the Moon slid in front of the Sun to create a solar eclipse. 

(Image: Francisco Sojuel)


An otherworldly lunar display captured two weeks ago (in three combined exposures) above Manitoba, Canada – moonlight refracted, reflected and diffused by millions of falling ice crystals. To wit:

The colourful rings are a corona caused by quantum diffraction by small drops of water or ice near the direction of the Moon. Outside of that, a 22-degree halo was created by moonlight refracting through six-sided cylindrical ice crystals. To the sides are moon dogs, caused by light refracting through thin, flat, six-sided ice platelets as they flittered toward the ground. Visible at the top and bottom of the 22-degree halo are upper and lower tangent arcs, created by moonlight refracting through nearly horizontal hexagonal ice cylinders. A few minutes later, from a field just off the road to work, the halo and arcs had disappeared, the sky had returned to normal — with the exception of a single faint moon.

Related: Halo You

(Image: Brent Mckean)


Behold: the south pole of the Moon. It’s up there amid the rugged lunar highlands near the top of this image captured recently from southern California. To wit:

At the Moon’s third quarter phase the lunar terminator, the sunset shadow line, is approaching from the left. The scene’s foreshortened perspective heightens the impression of a dense field of craters and makes the craters themselves appear more oval shaped close to the lunar limb. Below and left of centre is sharp-walled crater Tycho, 85 kilometres in diameter. Young Tycho’s central peak is still in sunlight, but casts a long shadow across the crater floor. The large prominent crater to the south (above) Tycho is Clavius. Nearly 231 kilometres in diameter its walls and floor are pocked with smaller, more recent, overlaying impact craters. Mountains visible along the lunar limb at the top can rise about 6 kilometres or so above the surrounding terrain.

(Image: Tom Glenn)


An image captured by the crew of Apollo 14 in 1971 from their command module Kittyhawk. To wit:

With Earth’s sunlit crescent just peaking over the lunar horizon, the cratered terrain in the foreground is along the lunar farside. Of course, while orbiting the Moon, the crew could watch Earth rise and set, but the Earth hung stationary in the sky over Fra Mauro Base, their landing site on the lunar surface. Rock samples brought back by the Apollo 14 mission included a 20 pound rock nicknamed Big Bertha, later determined to contain a likely fragment of a meteorite from planet Earth.

(Image: Apollo 14, NASA, JSC, ASU (Image Reprocessing: Andy Saunders))


Just over a year ago, on January 21, 2019, there was a total lunar eclipse. This horizontal composite tracks the Moon as it crossed into Earth’s dark umbral shadow in 35 consecutive frames. To wit:

Taken 3 minutes apart, they almost melt together in a continuous screen that captures the dark colours within the shadow itself and the northern curve of the shadow’s edge. Sunlight scattered by the atmosphere into the shadow causes the lunar surface to appear reddened during totality (left), but close to the umbra’s edge, the limb of the eclipsed Moon shows a remarkable blue hue. The blue eclipsed moonlight originates as rays of sunlight pass through layers high in Earth’s upper stratosphere, colored by ozone that scatters red light and transmits blue. The Moon’s next crossing into Earth’s umbral shadow, will be on May 26, 2021.

(Image: Laszlo Francsics)


Behold: Europa –  fourth largest of Jupiter’s 79 moons and fictional forbidden location of future intelligent life in Arthur C. Clarke’s ’2010: Odyssey Two’ (1982) and Peter Hyam’s 1984 film adaptation ‘2010: The Year We Make Contact’.

Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon’s icy surface likely hides a deep, global ocean. Galileo’s Europa image data has been remastered here, using improved new calibrations to produce a color image approximating what the human eye might see. Europa’s long curving fractures hint at the subsurface liquid water. The tidal flexing the large moon experiences in its elliptical orbit around Jupiter supplies the energy to keep the ocean liquid. But more tantalizing is the possibility that even in the absence of sunlight that process could also supply the energy to support life, making Europa one of the best places to look for life beyond Earth. What kind of life could thrive in a deep, dark, subsurface ocean? Consider planet Earth’s own extreme shrimp.

Larger image here.

(Image: NASA, JPL-Caltech, SETI Institute, Cynthia Phillips, Marty Valenti)


Behold: the sunlit crescent of da Vinci glow caused by earthshine (light reflected from a bright planet Earth) on the moon. To wit:

..a description of earthshine in terms of sunlight reflected by Earth’s oceans illuminating the Moon’s dark surface was written over 500 years ago by Leonardo da Vinci. One lunar month ago [this] da Vinci glow was captured in stacked exposures from the Badain Jilin Desert of Inner Mongolia, China. This year marks the 500th anniversary of Leonardo da Vinci’s death.

(ImageLikai Lin)