Astronomy Picture of the Day 11-23-02

NASA ^ | 11-23-02 | Robert Nemiroff and Jerry Bonnell

[petuniasevan]

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.

2002 November 23

Credit: NASA, Lunar Orbiter 4

Explanation: Like a target ring bull's-eye, the Mare Orientale is one of the most striking large scale lunar features. Located on the Moon's extreme western edge, this impact basin is unfortunately difficult to see from an earthbound perspective. It is over 3 billion years old, about 600 miles across and was formed by the impact of an asteroid sized object. The collision caused ripples in the lunar crust resulting in the three concentric circular features visible in this 1967 photograph made by NASA's Lunar Orbiter 4. Molten lava from the Moon's interior flooded the impact site through the fractured crust creating a mare. Dark, smooth regions on the moon are called mare (Latin for sea), because early astronomers thought these areas might be oceans.

[petuniasevan]

[MozartLover]

bump

[RightWhale]

If we could see Mare Orientale from the ground here on earth, there would be a lot more interest in the space program. There wouldn't be a child anywhere who was unaware of what that meant. It has happened to the earth, and it will happen again if we don't get off our country estates and do something about it.