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can retrace the astronauts' steps with greater clarity to see where they took lunar samples

In the Apollo 17 image, the foot trails, including the last path made on the moon by humans

One of the details that shows up is a bright L-shape in the Apollo 12 image. It marks the locations of cables running from ALSEP's central station to two of its instruments. Although the cables are much too small for direct viewing, they show up because they reflect light very well.

higher resolution of these images is possible because of adjustments made to LRO's orbit, which is slightly oval-shaped or elliptical

paths left by astronauts Alan Shepard and Edgar Mitchell on both Apollo 14 moon walks are visible in this image. (At the end of the second moon walk, Shepard famously hit two golf balls.)

he iconic image traveled nearly 240,000 miles in digital form from the Next Generation Satellite Laser Ranging (NGSLR) station at NASA's Goddard Space Flight Center in Greenbelt, Md., to the Lunar Orbiter Laser Altimeter (LOLA) instrument on the spacecraft.

By transmitting the image piggyback on laser pulses that are routinely sent to track LOLA's position, the team achieved simultaneous laser communication and tracking.

This is the first time anyone has achieved one-way laser communication at planetary distances

"In the near future, this type of simple laser communication might serve as a backup for the radio communication that satellites use

In the more distant future, it may allow communication at higher data rates than present radio links can provide

Typically, satellites that go beyond Earth orbit use radio waves for tracking and communication

LRO is the only satellite in orbit around a body other than Earth to be tracked by laser as well.

Precise timing was the key to transmitting the image

divided the Mona Lisa image into an array of 152 pixels by 200 pixels

Every pixel was converted into a shade of gray, represented by a number between zero and 4,095.

Each pixel was transmitted by a laser pulse, with the pulse being fired in one of 4,096 possible time slots during a brief time window allotted for laser tracking

he complete image was transmitted at a data rate of about 300 bits per second.

The laser pulses were received by LRO's LOLA instrument, which reconstructed the image based on the arrival times of the laser pulses from Earth

This was accomplished without interfering with LOLA's primary task of mapping the moon's elevation and terrain and NGSLR's primary task of tracking LRO.

The success of the laser transmission was verified by returning the image to Earth using the spacecraft's radio telemetry system.

Turbulence in Earth's atmosphere introduced transmission errors even when the sky was clear.

To overcome these effects,

employed Reed-Solomon coding, which is the same type of error-correction code commonly used in CDs and DVDs.

The next step after LLCD is the Laser Communications Relay Demonstration (LCRD), NASA's first long-duration optical communications mission.

The two Grail spacecraft — known as Ebb and Flow — slammed into a mountain near the lunar north pole at 3,771 mph (6,070 km/h), striking the surface about 20 seconds apart.

The Grail craters first showed up in LROC photos from January, but images taken on Feb. 28 show them in much greater detail

used these later photos to produce a topographic map of the impact zone

This map revealed that the two craters are separated by about 7,250 feet (2,210 m) in straight-line distance and 985 feet (300 m) in altitude

the crashes ejected material that appears darker than the surrounding lunar dirt.

these may be dark due to spacecraft material being mixed with the ejecta

may be residual fuel left in the probes' lines, or bits of their carbon-fiber bodies

LRO didn't get any images of the actual crashes, which occurred in the dark.

ultraviolet imaging spectrograph did see emissions from mercury and atomic hydrogen in the ejected plumes when they rose high enough to reach sunlight

The analysis of the Grail impact plumes is ongoing

The probes' measurements have allowed scientists to create the best-ever gravity map of any celestial body

And that map is getting better all the time, as researchers continue to analyze the data

The twin probes, which were each about the size of a washing machine, zipped around the moon at an average altitude of just 7 miles (11 km) in their final days

as well as the darker trails of the astronauts’ bootprints, including Armstrong’s jaunt eastward to the rim of Little West crater

the total area Neil and Buzz explored it would easily fit within the infield of a baseball diamond!

Armstrong’s visit to the crater’s edge was an unplanned excursion. He used the vantage point to capture a panoramic image of the historic site:

Previously the LROC captured the Apollo 15 landing site, which included the tracks of the lunar rover — as well as the rover itself

Arizona State University featured the latest similarly high-resolution view of the Apollo 12 site

This location has the honor of being two landing sites in one: Apollo 12 and the Surveyor 3 spacecraft, which had landed on April 20, 1967 – two and a half years earlier!

the US flag planted by Apollo 12 astronauts Pete Conrad and Alan Bean isn’t itself visible, the shadow cast by it is.

Apollo 12 was the only mission to successfully visit the site of a previous spacecraft’s landing, and it also saw the placement of the first Apollo Lunar Surface Experiments Package (ALSEP), which included a seismometer and various instruments to measure the lunar environment

spacecraft mapped Shackleton crater

using a laser to illuminate the crater's interior and measure its albedo or natural reflectance

laser light measures to a depth comparable to its wavelength, or about a micron

represents a millionth of a meter, or less than one ten-thousandth of an inch

used the instrument to map the relief of the crater's terrain based on the time it took for laser light to bounce back from the moon's surface. The longer it took, the lower the terrain's elevation.

addition to the possible evidence of ice, the group's map of Shackleton revealed a remarkably preserved crater that has remained relatively unscathed since its formation more than three billion years ago

Like several craters at the moon's south pole, the small tilt of the lunar spin axis means Shackleton crater's interior is permanently dark and therefore extremely cold

The crater's interior is extremely rugged

"It would not be easy to crawl around in there

Curiosity used both of her high resolution color mast mounted cameras to collect a series of Earth/Moon images

Processing has removed the numerous cosmic ray strikes

these are not the first images of the Earth from Mars orbit or Mars surface

NASA’s Mars Exploration Rover Spirit imaged Earth from the surface in March 2004, soon after landing

Mars Global Surveyor in 2003 and Mars Reconnaissance Orbiter in 2007

NASA’s Cassini orbiter at Saturn captured the Earth and Moon

in 2013

The three crewmembers are slated to spend a total of 15 days in orbit, which would make their Shenzhou 10 mission the longest manned spaceflight in China's history.

According to a statement from the China National Space Administration, the nation carried out a 40-day ground test to mimic the lunar environment, in an attempt to make sure that Chang’e 3 can endure the extreme temperatures on the moon

Chang'e 3 lunar probe consists of two main parts: a service module and a lunar landing vehicle

Dragon in Space, a website that monitors China's space program

the mission will be launched this December

The probe would land softly on the moon’s surface and deploy a six-wheeled rover to explore the areas surrounding the landing spot

Ready to watch the Chinese moon landing and rover action from above is NASA's Lunar Reconnaissance Orbiter (LRO

Looking further into the future, China's step-by-step robotic moon effort also includes a return to Earth of lunar surface materials

head of the National Astronomical Observatories of the Chinese Academy of Sciences and chief scientist of the lunar exploration program, said some lunar materials would be scooped up from the moon’s surface, while other material would be acquired from a depth of about 6.6 feet (2 meters).