The discovery of ice deposits in more than 40 craters in the moon’s North Pole by NASA’s Miniature -Synthetic Aperture Radar (Mini-SAR) forms “a positive direction for future explorations with respect to lunar resources and pursuit of pure science,” according to M. Annadurai, Project Director, Chandrayaan-1 and 2.
The Mini-SAR is one of the 11 scientific instruments that flew on board India’s Chandrayaan-1.
NASA’s Moon Mineralogy Mapper (M3), which was another instrument on board Chandrayaan-1, had earlier indicated that water was getting formed even in the sun-lit regions, he said.
Mr. Annadurai said: “We are seeing a large number of craters [with ice deposits]. That gives an indication of a good quantum of polar ice on the moon. Earlier, we had seen the physical phenomenon of water getting formed in one region. We are now seeing water getting retained in another region as ice deposits. This is called volatile transportation. These discoveries indicate that we had a good combination of instruments on board Chandrayaan-1. They could not have been made by other optical instruments which need sunlight to see what is there.”
J.N. Goswami, Principal Scientist, Chandrayaan-1, described the latest discovery as “an interesting and new result.”
He said: “It is quite interesting from our perspective. We thought it would be there, and it is there. I am confident that whatever signals we are getting are correct.”
Dr. Goswami, who is also Director, Physical Research Laboratory, Ahmedabad, made these remarks from the U.S., where he is on a visit now. What was significant was that water ice had been found both inside the craters and outside.
Earlier, water molecules were found on the moon’s soil by M3. “We are now finding it in solid form. So this is very important. Water is an important resource if people want to go to the moon,” Dr. Goswami said.
An Indian Space Research Organisation (ISRO) release said the Mini-SAR mapped the permanently shadowed polar craters not visible from the earth. The deposits had radar characteristics, similar to ice. The emerging picture from multiple measurements, and the resulting data from the Mini-SAR, M3 and the NASA’s Lunar Crater Observation and Sensing Satellite (LCROSS), indicated that “water creation, migration, deposition and retention are occurring on the moon,” it said, quoting Paul Spudis, principal investigator of the Mini-SAR experiment at the Lunar and Planetary Institute, U.S.
The Mini-SAR’s findings have just been published in the journal, Geophysical Research Letters. The findings were authored by scientists from 13 agencies from the U.S. and India, including Prof. Goswami and M. Chakrabarty of the Space Applications Centre, Ahmedabad. “The new findings add to the growing scientific understanding of multiple forms of water on the moon,” the release said.
Scientists of the Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram, had also obtained “very clear signature of H2O (18 atomic mass unit, or amu) intensifying” in the thin atmosphere of the moon. The Moon Impact Probe (MIP) of Chandrayaan-1, carrying a sensitive mass spectrometer called ChACE (Chandra’s Altitudinal Composition Explorer), made this discovery as the MIP raced towards the moon’s surface for more than 20 minutes on November 14, 2008. While the VSSC built the MIP, the SPL developed the ChACE. Chandrayaan-1 was launched on October 22, 2008.