LONAR (BULDANA): There's an air of expectancy over the Spirit rover's
exploits on Mars, but not many know that this place on earth is one
of the main reasons why it is so.
Coinciding with the Mars exploration, a geophysicist associated with
the National Aeronautics and Space Administration (NASA) is studying
the surface of one of only two impact craters created by a meteor
strike on basaltic land, which is located at Lonar in Maharashtra.
Horton Newsom, a research professor, is here to collect samples on
NASA's request in a bid to unlock the mysteries of the Martian
surface. The reason is the uncanny similarities between the Lonar
crater and those on Mars which have also been formed in basalt.
The Spirit rover has already wandered over the surface of one such
Martian crater, a much bigger one though. Newsom, from the Institute
of Meteoritics at New Mexico University in US, was one of those
responsible for selecting the site.
By comparing samples from Lonar with those from Mars, scientists hope
to solve the one big riddle surrounding the red planet: Did it ever
contain water, could it ever support life?
``Lonar comes closest to Martian craters in terms of chemistry,''
Newsom told this website's newspaper. ``Since not much is known about
the other only basaltic crater, which is in Russia, Lonar offers
great prospects for better understanding of Mars.''
Newsom, in fact, is part of a four-member Lonar exploration team
along with co-scientists Soumitra Misra, D.Sengupta and
V.L.Narasimhan from IIT, Kharagpur.
The team's study is aimed at identifying major alterations
(conversion of rock to soil) and to check if this was due to impact-
induced hydrothermal activity (which takes place after groundwater
seeps through fractures caused by the collision of the meteor with
the host rock).
In a paper published in a journal called Meteoritics and Planetary
Science last year, Newsom had claimed that the 50,000-year old, 1.8-
km diameter crater at Lonar offers an excellent analog for similarly-
sized craters on Mars as it has a composition similar to that of
Martian meteorites.
``The presence of calcite as the main late-stage mineral in the Lonar
samples is consistent with the alterations by meteoric water and also
supports use of Lonar as an analog to Mars,'' Newsom said.
``Hydrothermal alterations at Lonar suggest Lonar-sized Martian
craters may also have potential to form hydrothermal systems leading
to such alterations if water is present there in some form,'' he
said. ``With impact craters' known ability to access shallow ground
water, this could have become possible on Mars as well.''
Newsom has also done some geo-chemical modelling of Martian basalt
alterations to strengthen the analogy. ``Our results suggest Lonar
has great potential as a laboratory for Martian study, and needs to
be urgently protected,'' he said.
The warning could not have been better timed. Use of chemical
fertilisers and pesticides by farmers doing agriculture right inside
the crater poses a serious ecological danger to the site.
``Many such warnings have been issued so far,'' says S.T.Bugdane, a
local teacher and an amateur geology enthusiast. Thick plantations on
the slopes of the crater are dwindling, with the result that rains
cause the soil to slide down and get accumulated at the base, he
said. ``Some of the 18 beautiful temples at the crater's base have
disappeared as water levels rise,'' he said.
Authorities are, at long last, waking up. Says District Collector
Dinesh Waghmare: ``The Forest Department has declared it a wildlife
sanctuary, so there's hardly anything we can do besides giving them
funds. We gave them Rs 45 lakh last year for purposes like chain-
fencing and a nature interpretation centre, but they returned it,''
he said.
Deputy Conservator of Forest Shailesh Tembhurnikar says the measures
could not be implemented as some environmentalists had reservations.
But there are plans to declare Lonar a World Heritage site as it
needs to be retrieved from the present mess, Bugdane said. As of now,
that appears to be Lonar's best bet.