The mission objective of NASA’s Ebb and Flow lunar gravity measuring orbiters was to map variations in density and topography of the Moon’s surface, the Mass concentrations, or masscons, that affected objects in lunar orbit. In mid-December of last year, the two craft were de-orbited to crash into a lunar mountainside, but Ebb and Flow successfully returned a rich dataset that identified the locations of the Moon’s masscons, most of them originating from huge asteroidal impacts in the early lunar history.

This gravity map, centered around Mare Moscoviense on the far side of the Moon, shows deviations from the mean density that a featureless, evenly dense body would have, as measured in a unit of acceleration called milliGals. For the visualization, mapped over a digital elevation model of lunar terrain from the Lunar Reconnaissance Orbiter, dark purple is at the low end of the range, and red is at the high end, with yellow as the mean (image credit: NASA/Goddard Space Flight Center Scientific Visualization Studio).

NASA’s Messenger space probe looked back at the Earth and Moon against the constellation of Libra from 114 million miles sunward. The probe captured this image in May of 2010 while searching for faint, theoretical vulcanoids, asteroids that might be orbiting the sun inside Mercury’s orbit (image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington).

Harvest Moon tonight, and the 2006 song Satellite by Guster has been in my head all day (moon image credit: NASA/Goddard Space Flight Center Scientific Visualization Studio).

He went in peace, for all humankind (image credit: NASA).

43 years ago today, my father sat me in front of a television set (I was almost two years old) to watch as NASA’s Apollo 11 lander touched down on the surface of the Moon’s Sea of Tranquility with astronauts Buzz Aldrin and Neil Armstrong aboard. On the lander left on the lunar surface was this plaque, signed by President Nixon: “Here Men From The Planet Earth First Set Foot Upon the Moon, July 1969 A.D. We Came in Peace For All Mankind.”

Watch coverage of the moon landing on 43 year delay on this site today, beginning at 4:10PM EDT (image credit: NASA). 

At the edge of the Vallis Alpes on the Moon lies Trouvelot Crater (center right in this image), named for French astronomer, amateur entomologist, and artist Étienne Léopold Trouvelot. Though he spent his latter years producing thousands of astronomical illustrations, M. Trouvelot is more (in)famous for his role in accidentally introducing the European gypsy moth to North America. In the late 1860s he imported gypsy moth eggs to his home in Medford, Massachusetts, intending to cross-breed silk-producing moths with the disease resistant pests. Some of the insects escaped from his backyard and began to spread and multiply. By now, the pests cause an estimated $868 million per year in damage to trees of North America.

M. Trouvelot’s misfortune in his entomological endeavours led him to pursue a new career in astronomical observation and illustration, beginning in the 1870s (image credit: NASA/Lunar Orbiter 4/Lunar Planetary Institute).

The Moon’s Mare Humorum, or Sea of Moisture, as observed by French astronomer, amateur entomologist, and artist Étienne Léopold Trouvelot in 1875. Though he spent his latter years producing thousands of astronomical illustrations, M. Trouvelot is more (in)famous for his role in accidentally introducing the European gypsy moth to North America. In the late 1860s he imported gypsy moth eggs to his home in Medford, Massachusetts, intending to cross-breed silk-producing moths with the disease resistant pests. Some of the insects escaped from his backyard and began to spread and multiply. By now, the pests cause an estimated $868 million per year in damage to trees of North America.

M. Trouvelot’s misfortune in his entomological endeavours led him to pursue a new career in astronomical illustration, after he observed several aurorae in 1870. He joined the staff at the Harvard College Observatory in 1872, and was invited to use the 26 inch refractor at the U.S. Naval Observatory for a year in 1875. A portfolio of his pastel astronomical observations was published in 1881 (image credit: The Trouvelot astronomical drawings: Atlas/NYPL Digital Gallery).

Northern Native American tribes like the Algonquin knew tonight’s full moon as the Worm Moon, the last moon of winter coinciding with the spring thaw, when earthworm casts began to appear, along with the robins.

The psychological phenomenon known as pareidolia led to cultures of the Northern Hemisphere imagining a “Man in the Moon” beaming down at us, his facial features made up of maria, ancient seas of dark lava.

A new research paper from Caltech proposes that the reason that those maria are mostly located on the side facing the Earth may be due to the same tidal forces that slowed the moon’s rotational day to be about the same as its orbital period, flexing lava across one face of the moon in a tidal bulge (image credit: NASA/Goddard Space Flight Center Scientific Visualization Studio).

This week’s waxing Moon, its night side lit by reflected light from our planet even as its day side reflects the brilliant light of our Sun. Compare to this image of Saturn’s moon Enceladus, with its night side lit by sunlight reflected by the gas giant (image credit: Mick Hyde - reposted with permission).

On Tuesday this week, our Moon passed between the Sun and NASA’s Solar Dynamics Observatory orbiting our planet, giving earthbound team scientists a rare opportunity to calibrate the telescope’s optics. In this view in extreme ultraviolet, the sharp edge of the lunar disc partly covered an active region of sunspot activity (image credit: NASA/SDO).

The Earth and its moon as seen in 1992 by NASA’s Galileo spacecraft, on its way past us to the planet Jupiter. The craft was named for Italian Renaissance scientist Galileo Galilei, who was born on this date in 1564. Galileo famously ran afoul of Pope Urban VIII for championing the idea of heliocentrism, that the Earth and other bodies of tour solar system orbit the sun, for which he was tried by the Inquisition and found guilty of heresy.

The Galileo spacecraft explored the Jovian system of moons discovered by its namesake for years, before burning up in Jupiter’s atmosphere in September of 2003 (image credit: NASA/JPL/color composite Gordan Ugarkovic).

Moonset over Afghanistan, as seen from the International Space Station (photo by NASA Astronaut Ron Garan, aboard the ISS).

First view of an Earthrise over the Moon, taken 45 years ago today by Lunar Orbiter 1 on August 23, 1966. The image was newly restored by the Lunar Orbiter Image Recovery Project at NASA Ames Research Center (image credit: NASA/LOIRP).

Last look back at the International Space Station from Space Shuttle Atlantis as it prepares to return to earth for the last time. On the 42nd anniversary of the first Apollo landing, the moon behind the ISS seems farther away than ever (image credit: NASA).

Moonset as seen from the ISS, today (photo by NASA Astronaut Ron Garan, Expedition 27/28)