Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2017 October 25
See Explanation.  Clicking on the picture will download
 the highest resolution version available.

Marius Hills and a Hole in the Moon
Image Credit: NASA, Lunar Orbiter 2; Inset: Lunar Reconnaissance Orbiter

Explanation: Could humans live beneath the surface of the Moon? This intriguing possibility was bolstered in 2009 when Japan's Moon-orbiting SELENE spacecraft imaged a curious hole beneath the Marius Hills region on the Moon, possibly a skylight to an underground lava tube. Follow-up observations by NASA's Lunar Reconnaissance Orbiter (LRO) indicated that the Marius Hills Hole (MHH) visually extends down nearly 100 metres and is several hundred metres wide. Most recently, ground penetrating radar data from SELENE has been re-analyzed to reveal a series of intriguing second echoes -- indicators that the extensive lava tubes exist under Marius Hills might extend down even kilometres and be large enough to house cities. Such tubes could shelter a future Moon colony from large temperature swings, micro-meteor impacts, and harmful solar radiation. Potentially, underground lava tubes might even be sealed to contain breathable air. These lava tubes likely formed when lunar volcanos were active billions of years ago. Pictured, the surface of Marius Hills region was captured in the 1960s by NASA's Lunar Orbiter 2 mission, while an inset image of the MHH is shown from NASA's continuing LRO. Several volcanic domes are visible, while Marius Crater is visible on the upper right.

Tomorrow's picture: the cosmic sea


< | Archive | Submissions | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
NASA Web Privacy Policy and Important Notices
A service of: ASD at NASA / GSFC
& Michigan Tech. U.