NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) — pronounced "laddie," not "lady" — is set to launch to the moon in early September 2013.
The 844-pound (383 kilograms) spacecraft is designed to orbit the moon, investigating lunar dust, the lunar atmosphere and conditions near the moon's surface, NASA officials have said.
"While we know Earth's atmosphere has oxygen, we do not know what comprises the moon's atmosphere," NASA officials wrote in a fact sheet. "To help us understand what it contains, LADEE will dip into the lunar atmosphere, and instruments onboard the spacecraft will send detailed measurements to scientists to analyze on Earth." [Photos: NASA's LADEE Moon Dust Mission in Pictures]
The moon's atmosphere is much thinner than Earth's. Scientists suspect that the lunar atmosphere is about 1/100,000th the density of Earth's; they therefore consider it a vacuum.
Because the atmosphere is so thin, temperatures reach 273 degrees Fahrenheit (134 degrees Celsius) on the sunny side of the moon, but the temperature can get as cold as -243 degrees Fahrenheit (-153 degrees Celsius) on the far side of the moon.
The moon's atmosphere can be compared to the fringes of Earth's atmosphere, the area of space where the International Space Station orbits, NASA officials wrote. Scientists also suspect that the moon's atmosphere could be analogous to the atmospheres of other relatively small planetary bodies throughout the solar system.Following in lunar footsteps
LADEE is the latest in a long line of probes NASA has sent to the moon.
The space agency's Pioneer 4 completed the first successful American flyby of the moon in 1959. The Soviet spacecraft Luna 1 successfully flew by the moon a few months earlier. [How NASA's LADEE Spacecraft Works (Infographic)]
After sending various spacecraft to the natural satellite throughout the 1960s and 1970's, and successfully landing a manned vessel on the lunar surface in 1969, NASA didn't send another spacecraft to the moon until the Clementine orbiter in 1994.
In 2011, the Lunar Reconnaissance Orbiter sent back the most high-resolution moon map ever constructed.
That same year, the twin GRAIL (Gravity Recovery And Interior Laboratory-A) spacecraft launched. The two probes, responsible for investigating the structure of the lunar interior, were purposefully crashed into the moon in December 2012.LADEE's Science
The LADEE spacecraft comes equipped with three science instruments and a technology demonstration:Ultraviolet and Visible Light Spectrometer – This instrument will analyze the light signatures of materials around the moon to understand the composition of the satellite's atmosphere.Lunar Dust Experiment – This instrument will collect and analyze moon dust in the atmosphere. The instrument could also help NASA scientists solve a mystery, NASA officials wrote in a facts sheet: "Was lunar dust, electrically charged by solar ultraviolet light, responsible for the pre-sunrise horizon glow that the Apollo astronauts saw?"Neutral Mass Spectrometer – The spectrometer will look for variations in the lunar atmosphere while the moon is in different orbits and various space environments, according to NASA officials.Lunar Laser Communications Demonstration – For this technology demonstration, LADEE will use lasers (and not radio waves, like other spacecraft that have flown beyond close Earth orbit have used) to communicate with controllers on Earth. This could allow the spacecraft to communicate at broadband speeds with the ground.A history-making launch
The LADEE launch will be the first deep-space mission to launch from NASA's Goddard Space Flight Center's Wallops Flight Facility in Virginia. This mission also marks the first time a payload has been launched aboard a U.S. Air Force Minotaur V rocket integrated by Orbital Sciences Corp., NASA officials have said.
Once launched, the probe will take about 30 days to get to the moon; LADEE will then go through a checkout period for another 30 days. After that, the probe is scheduled to conduct 100 days of science operations.