Hyderabad : City-based scientists have discovered new seismically active zones on the moon in a major development that may impact future missions taken up by ISRO. With space agency’s futuristic Chandrayaan-2 aiming for a landing near the lunar south pole -which is in close proximity to newly-discovered faults -the findings will provide an opportunity to further study the phenomenon of moonquakes.
A team, led by P Senthil Kumar, senior scientist at the CSIR-National Geophysical Research Institute (NGRI) in Hyderabad, was behind the crucial discovery published in the American Geophysical Union’s Journal of Geophysical Research Planets on February 19. The study titled “Recent shallow moonquake and impact-triggered boulders falls on the moon: new insights from the Schrodinger basin“, unravelled young faults, where shallow moonquakes possibly occurred in recent times. The scientists’ research was aided by highresolution terrain mapping camera images obtained by Chandrayaan-1 orbiter. The images provided the first glimpse of the presence of seismically active fault zones, called lobate scarps, on the interior of the 320-km diameter Schrödinger basin.According to Kumar, Schrodinger basin is considered a high-priority landing site by the international planetary science community , including NASA. The basin was created by a huge asteroid impact about 3,800 million years ago.
Kumar says analysis of orbiter images provided new evidence of upward movement of faulted blocks and surface ruptures. “Since this impact basin excavated the floor of the South Pole Aitken basin and has many interesting geological features, the new finding of seismically active zones in the basin interior, opens up a new opportunity to study recent and possibly on-going seismic activities,“ Kumar said. He added, “One of the longest faults is just 10 million years old and a few segments of this fault could be very recent,“ the scientist said.
Among evidence sought to determine is data from seismometers installed there (by Apollo astronauts) and the occurrence of `boulder falls’ on slopes on the moon. Moonquakes were recorded during 1969-1977 period by seismometers which registered a few shallow ones annually .They were shown to resemble intra-plate quakes on earth. Hundreds of boulders tumbled, rolled, and jumped on the slopes due to low-to-moderate levels of ground shaking possibly caused by the shallow moonquakes. While boulder falls could also be triggered by meteoroid impacts, rolling of boulders seen near faults are most likely due to quakes, according to the study.
-from Times of India