AHMEDABAD:
Five years ago India launched its first successful Moon mission,
Chandrayaan I. Now, with Mangalyaan, India will become the fourth nation
in the world to take the first step to Mars, if it successfully
positions a spacecraft in the red planet's orbit.
As the
countdown to India's maiden Mangalyaan, Mars Orbiter Mission (MOM)
begins, Dr A S Kiran Kumar, director of Space Applications Center (SAC)
of
Indian Space Research Organization
(Isro) provided a glimpse into the mission, the challenges his team
faced and how India's "affordable" mission, has several dimensions
-conducting scientific experiments, demonstrating technological
capabilities and creating the necessary credentials to be part of future
international space missions.
Importance of the project
The earliest attempts for exploration of the red planet began in 1960s
at the height of 'space race' between US and the USSR when a number of
missions were planned. The first mission was USSR's Marsnik 1 in October
1960 which failed to reach even the Earth's orbit. The US's Mariner 4
in November 1965 provided the first glimpse of the Martian surface
during its fly-by mission. Since then, there have been a number of
missions to probe the red planet, primarily by US'
Nasa,
including two rovers - Pathfinder and Curiosity - that have provided a
full map of the planet and information of its atmosphere, soil
composition and other aspects.
What does Mangalyaan intend to achieve?
"This is primarily a technological mission, considering its stringent
precision requirements. The challenge before Isro is to put the
spacecraft into a precise 50 km imaginary cube when it enters Mars
gravitational field, around 250 million km away, while scientists
control its 11-month journey and orientation. It requires a proper
design, planning, management and operations," says Kumar.
Technological challenges "On August 15, last year Prime Minister
Manmohan Singh
announced India's intention to send an orbiter to Mars. In 14 months,
Isro was ready with an orbiter craft. The only experience Isro has with a
mission to another celestial body is Chandrayaan I to the Moon," says
Kumar. Other space powers - US, Russia and
European Space Agency
(ESA) - have, independently or in collaboration, conducted a number of
experiments providing them chances to improvise. India is going with
it's trusted PSLV-XL launcher which was used for Chandrayaan, albeit
with modifications.
The task "We sent
Chandrayaan-1 to the Moon which was at a distance of 384,000 km, a
challenge before us five years ago. It has been multiplied 1,000 times
with the Mangalyaan mission, as we are now going 360,000,000 km away
from Earth. Till Chandrayaan, we were concerned with Earth's gravity.
For the first time, our probe will leave the Earth's influence, enter
the Heliosphere - the region dominated by the Sun's gravity - before it
enters Mar's gravitational field. The maximum Earth to Mars roundtrip
light time (RLT) will be 42 minutes during the mission, meaning the
signal (command) we send from Earth will reach the craft 21 minutes
later and will take the same time for us to receive it back. Thus, we
need to give a bit of autonomy to the craft to address emergencies,"
says Kumar. In order to take advantage of the window when the craft can
reach Mars using minimum fuel, India has chosen October 28 this year.
Such an opportunity comes at intervals of about 780 days.
Challenges ahead
It will be a 300-day journey for the craft in three phases -
Geo-centric phase, Helio-centric phase and finally the nail-biting
Martian phase-which will be around 573,000 km from Earth's surface.
"If we don't propel the craft enough, it will fall into a circular
orbit and eventually crash on the Martian surface. If we propel it too
much, it will go away from the planet and be lost in space. We have
designed an elliptical orbit for the craft where the nearest distance
will be 364 km and the farthest 80,000 km. Such an orbit will provide a
unique opportunity to observe Mars from a distance where the planet will
rotate on its axis and we will be able to capture most of its surface
barring some polar areas," Kumar says.
He adds that they have
subjected the payload and instruments to intense testing. "A craft
encounters a number of issues while in space. While communication is
always a concern, another issue is energy from the solar panels. As the
craft encounters blackouts -periods in the shadow of the planet and
can't receive energy - there are also periods of white-outs when the
craft is bombarded with solar plasma and can't function for a while. We
have taken such instances in consideration," he says.
At Mars
The craft is scheduled to reach the Mars orbit on September 21, 2014.
There are five payloads on board including a Lyman Alpha Photometer,
Methane Sensor for Mars, Mars Exospheric Neutral Composition Analyser,
Mars Colour Camera and Thermal Infrared Imaging Spectrometer.
The road ahead
Isro is buzzing with activity - not just for MOM but also for a slew of
projects, scheduled for the next five years. Kumar says that a
successful Mars mission will not only boost India's confidence but also
open doors for next-generation technology which will help future space
endeavours. After Mangalyaan, ISRO is planning Chandrayaan II which will
have a rover to collect and analyze samples from the lunar surface.
India is also planning to launch its first dedicated astronomy satellite
-
ASTROSAT
- after which the ambitious Aditya project will come into action. The
project intends to study Coronal Mass Ejection (CME) from L1, one of the
Lagrangian points between Sun and Earth which will facilitate the
craft's remaining at the same position with least effort, for the
observation.
About manned space missions, Kumar says it would
be the next logical step. "We are slowly building capacity for it and I
hope it culminates at an opportune time. Our immediate goal is to put
man in orbit (Lower Earth Orbit). The next one will be to prolong the
mission and later to conduct space flights," he said.
Space and human development
SAC officials believe that the constantly-pushed boundaries of
technological prowess can improve overall human resource development
(HRD) for the country through research and development and operational
capabilities. Kumar says that the successful missions not only encourage
scientists to surge ahead but also inspire millions of young minds.
"From my experience, I can say that nothing is difficult if we take a
motivated group and provide a specific goal," Kumar says.
