NASA has launched its latest mission to the Moon. An unmanned probe lifted off from the Wallops rocket facility on the east coast of the United States on schedule at 11.27pm on Friday.
Its $US280 million mission is to investigate the tenuous atmosphere that surrounds the moon.
The BBC reports the Lunar Atmosphere and Dust Environment Explorer will also try to get some insights on the strange behaviour of moondust, which appears on occasions to levitate high above the surface.
"The moon's atmosphere is really, really thin," said programme scientist Sarah Noble.
''The individual molecules are so few and far between that they don't interact with each other; they never collide. It's something we call an exosphere.
''The Earth has an exosphere as well, but you have to get out past where the International Space Station orbits before you get to this condition that we can consider an exosphere. At the Moon, it happens right at the surface."
US astronauts first walked on the Moon in 1969, and the last explorers of the Apollo era visited in 1972.
The journey to the Moon will take about a month and the probe will initially orbit at a height of about 250km for 40 days before moving lower for the science portion of its mission.
After 100 days spent measuring chemical variations in the lunar atmosphere, analysing exosphere gasses and lunar dust grains and looking for water molecules in the lunar atmosphere, LADEE will end its mission by crashing into the Moon.
As well as its three science instruments, LADEE carries a demonstration laser telecommunications payload.
The BBC reports engineers hope the test terminal will achieve download rates in the region of 600 megabits per second.