Mumbai: India will install Imaging
Riometer at its permanent research station in Antarctica in a
few months time to study the absorption of radio noise in
the lowest part of ionosphere, a top scientist from the Indian
Institute of Geomagnetism said here.
"The three-member team, led by IIG scientist P Elango,
will assemble and install an array of 16 receivers of Imaging
Riometer," IIG director Dr Archana Bhattacharyya said.
Elango and K U Nair of IIG have already reached the
station 'Maitri' while C Selvaraj will join them on November
30, she said.
"It would take at least two to three months to
complete the installation of the Riometer because of difficult
terrain and strong wind conditions prevailing at 'Maitri',"
she said.
The IR will collect data on the absorption of 38 MHz
radio noise in the lowest part of the ionosphere, at altitudes
between 50 and 110 km, over Antartica, Bhattacharya said.
Additional ionisation is produced in the atmosphere at
high latitudes due to precipitation of energetic charged
particles.
The particles are generated during solar flares or
geomagnetic storms caused by geo-effective Coronal Mass
Ejection (CME) from Sun or high speed solar wind from Coronal
Holes on the Sun, she explained.
In Antarctica, India is the sixth country, after
Australia, Britain, China, Denmark, and Japan to install this
permanent IR to collect data on radio signal absorption in the
lower ionosphere over a region not covered by the other IRs,
Bhattacharya said.
"However, the region around 'Maitri' has very low
magnetic field compared to the Arctic region, and the magnetic
field is also decreasing more rapidly. Therefore, greater
precipitation of particles is expected and hence the IR study
is taken up by IIG," she said.
Meanwhile, in the Arctic region, six such instruments
are operational that have been installed by few western
countries, she added.
IIG scientists will study how the particle
precipitation changes the ionospheric environment in terms of
its electrical conductivity, in response to transient events
on the sun.
Earlier India had carried out a Magnetic Survey and
also Global Positioning System (GPS) observations at Larsemann
Hills in East Antarctica and mapped the magnetic anomalies in
that region, which was published in the scientific journal
'Current Science' last year.
Bureau Report
First Published: Thursday, November 19, 2009, 16:00