Washington, Aug 20 : NASA? s Lunar Reconnaissance Orbiter (LRO) spacecraft has revealed cliffs in the lunar crust indicating that the moon shrunk in the geologically recent past and might still be shrinking today.
The results provide important clues to the moon''s recent geologic and tectonic evolution.
The Moon was formed as a result of collisions between asteroids and meteors, causing it to heat up. Now, over the years, as it cools off, it is shrinking in size, say scientists.
"Based on the size of the scarps, we estimate the distance between the moon''s center and its surface shrank by about 300 feet," said Dr. Thomas Watters.
Over recent geologic time, as the lunar interior cooled and contracted the entire moon shrank by about 100 m. As a result its brittle crust ruptured and thrust faults (compression) formed distinctive landforms known as lobate scarps.
These lobate scarps can help the team reconstruct the tectonic and thermal history of the moon over the past billion years.
Because the scarps are so young, the moon could have been cooling and shrinking very recently, according to the team.
"The ultrahigh resolution images from the NACs are changing our view of the moon," said Dr. Mark Robinson.
"We''ve not only detected many previously unknown lunar scarps; we''re also seeing much greater detail on the scarps identified in the Apollo photographs," he added. (ANI)