NASA LADEE Mission ends with planned lunar impact

Ground controllers at NASA's Ames Research Center in Moffett Field, Calif., have confirmed that NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft impacted the surface of the moon, as planned, between 9:30 and 10:22 p.m. PDT Thursday, April 17.

LADEE lacked fuel to maintain a long-term lunar orbit or continue science operations and was intentionally sent into the lunar surface. The spacecraft's orbit naturally decayed following the mission's final low-altitude science phase.

During impact, engineers believe the LADEE spacecraft, the size of a vending machine, broke apart, with most of the spacecraft's material heating up several hundred degrees – or even vaporizing – at the surface. Any material that remained is likely buried in shallow craters.

"At the time of impact, LADEE was traveling at a speed of 3,600 miles per hour – about three times the speed of a high-powered rifle bullet," said Rick Elphic, LADEE project scientist at Ames.

"There's nothing gentle about impact at these speeds – it's just a question of whether LADEE made a localized craterlet on a hillside or scattered debris across a flat area. It will be interesting to see what kind of feature LADEE has created."

In early April, the spacecraft was commanded to carry out maneuvers that would lower its closest approach to the lunar surface.

The new orbit brought LADEE to altitudes below one mile (two kilometers) above the lunar surface.

This is lower than most commercial airliners fly above Earth, enabling scientists to gather unprecedented science measurements.

On April 11, LADEE performed a final maneuver to ensure a trajectory that caused the spacecraft to impact the far side of the moon, which is not in view of Earth or near any previous lunar mission landings.

"It's bittersweet knowing we have received the final transmission from the LADEE spacecraft after spending years building it in-house at Ames, and then being in constant contact as it circled the moon for the last several months," said Butler Hine, LADEE project manager at Ames.

Launched in September 2013 from NASA's Wallops Flight Facility in Virginia, LADEE began orbiting the moon Oct. 6 and gathering science data Nov. 10.

The spacecraft entered its science orbit around the moon's equator on Nov. 20, and in March 2014, LADEE extended its mission operations following a highly successful 100-day primary science phase.

NASA LADEE Mission: Monitoring Lunar Dust

Artist’s concept of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft in orbit above the moon as dust scatters light during the lunar sunset. 

Credit: NASA Ames 

In partnership with NASA's Ames Research Center in Silicon Valley, Calif., Goddard's Wallops Flight Facility will launch the Lunar Atmosphere and Dust Environment Explorer (LADEE) in September, a robotic mission that will study the moon's thin atmosphere and dust particles.

Ames manages the 100-day mission—-which will attempt to confirm whether dust caused a mysterious glow on the lunar horizon astronauts observed during several Apollo missions—and Goddard plays a variety of key roles in LADEE.

After launch, Ames will control the spacecraft and execute mission operations. Goddard is responsible for the LADEE launch and several important LADEE components, including the instruments, demonstrations of the mission's payload and science operations.

"We wanted to do a mission that would benefit both centers," LADEE payload manager Robert Caffrey said. "It's a good model for centers working together to achieve common goals."

LADEE's launch in September from Virginia's Eastern Shore marks the facility's first launch to the moon.

Wallops will provide the launch services and range operations as well the launch vehicle, a U.S. Air Force Minotaur V rocket. LADEE will be the first spacecraft to launch on this rocket.

One of Goddard's biggest roles on LADEE is to manage the mission's four instruments and demonstrations. Three of the payload instruments—the Neutral Mass Spectrometer or NMS, Ultraviolet and Visible Light Spectrometer and the Lunar Dust Experiment or LDEX—will study the lunar atmosphere composition and analyze lunar dust.

Developed at Goddard, the NMS will measure variations in the different gases of the lunar atmosphere while the spacecraft orbits the moon. A similar spectrometer will fly aboard the Mars Atmosphere and Volatile Evolution Mission, scheduled to launch in November

"The Goddard Neutral Mass Spectrometer team is delighted to provide this instrument to the LADEE mission and contribute to this mission's exploration of the tenuous atmosphere of the moon," said Goddard NMS Principal Investigator Paul Mahaffy.

LADEE will also host the Lunar Laser Communications Demonstration or LLCD mission payload. LLCD is an innovative laser technology that could one day replace radio waves currently used in satellite communications and is expected to transmit more data at faster rates.