India's mission to Mars

Hours before Orbiter's scheduled launch this Tuesday, a run-down on the historic mission which, if successful, will place India in the very select interplanetary exploration club of the US, Russia and Europe.

The Satish Dhawan Space Centre in Sriharikota, 100-km outside Chennai, is buzzing with activity. Over the past few months, the dusty little town, close to the picturesque Pulicat lake, has been taken over by a team of scientists from Indian Space Research Organisation (Isro) on an ambitious mission: to send off a Mars Orbiter on India's maiden flight to the Red Planet. On Thursday, nearly 300 scientists are anxiously watching the launch rehearsal of the Mars Orbiter. As they manoeuvre the countdown sequence at the launch pad, there are some visible moments of tension, which soon get buried under smiles, cheers and congratulatory pats.

The rehearsal, which began at 6.08 am and ended at 14.38 pm, simulated the exact conditions as those on the launch date on November 5. The 76-metre mobile service tower with 32 wheels that surrounds the actual spacecraft is pushed back 150 metres, just as it will be done on the launching day. It lays bare the massive PSLV -XL, which is ready for its virtual lift off.

"It is a historic mission as its an inter-planetary mission using all indigenous payloads. Since it is the 25th PSLV mission, we are all the more excited," says A Lawrence, the man in-charge of the launch pad.

Seven km away stands the Mission Control Centre which is the nerve centre of the launch pad. A large group of scientists sit there glued to their systems, monitoring the total countdown sequence. Some are checking the flight parameters, while others are closely monitoring the electrical checks. The remaining few are giving last-minute checks to the entire trajectory that goes up to the satellite injection. Finally, after several hours of monitoring, the scientists and engineers declare the launch rehearsal a success.

Virtual take-off
But this success is still virtual, where the propellants haven't been filled and the satellite hasn't lifted off. It's just a small beginning to the long and mysterious space voyage of more than 300 days that India will embark on at 14.38 pm on November 5.

"Except for the ignite button, all other procedures were checked today. All the vehicle systems powered up and the health of the systems were found to be normal," says P Kunhikrishnan, Project Director, PSLV, adding, "Everything went off smoothly. Now we are preparing for the countdown which begins on November 3".

This mission, he insists, is different. "In the previous missions, satellite injections would take place after 20 minutes. This time, it will take place after more than 40 minutes. Also, since the temperature will fall drastically, thermal control features have been added." The more than 16,000 employees of Isro, who have made the technological and scientific contributions to the mission are aware that even after the spacecraft is launched, the road ahead is dotted with challenges before it finally enters the Martian orbit on September 24, 2014. But the scientists are upbeat. "Every mission has a failure risk. That does not mean that you do not foray into it," says Vijaya Sardhi, group director, programme management. Agrees Mylswamy Annadurai, the project director of the Chandrayaan-1 and Chandrayaan-2 missions: "We are all optimistic, but at the same time we are all praying that the mission meets its goals and objectives. Considering that there have been several missions to Mars but few have actually succeeded, we have to be careful."

Many moons ahead
It's a giant leap ahead from India's 2008 moon mission. "You cannot compare the two. In Chandrayaan-1, we had to cover a distance of around 4 lakh km, the travel distance now is nearly 200 to 400 million km. Also, Chadrayaan-1 remained within the Earth's sphere of influence all along. The Orbiter will move from the Earth's sphere of influence to the Sun's sphere of influence, and finally to Mar's sphere of influence," explains Annadurai.

The countdown for the Mars Mission begins on November 3 at 6:08 am. The total countdown time is 56 hours and 30 minutes, during which the propellants will be filled. Originally, the launch date was scheduled for October 28, but bad weather conditions forced Isro scientists to postpone it. Compared to the earlier PSLV missions, this one has a long coasting phase of nearly 27 minutes between the third stage (PS3) burn-out and the fourth stage (PS4) ignition.

The total flight duration before the injection of the Orbiter is nearly 47 minutes, much more than the usual flight time of 20 minutes. This is to achieve the correct argument of perigee at the time of the spacecraft's injection from PS4. The small five minutes launch window that opens at 14:38 hours on November 5 will be closely monitored not just by India but also the world. And if the Orbiter makes it to Mars, India will join the select club of the US, Russia and Europe, to have a close encounter with the Red Planet.

Martian trivia
Mars is named after the Romans God of War. It's also called the Red Planet because the iron oxide on its surface makes it appear red.

The atmosphere of Mars consists of 95.32 per cent carbon dioxide.

Mars can be spotted with the naked eye.

Mars is half as wide as Earth and has about a tenth of its mass.

The average temperature on Mars is minus 63 degrees Celsius.

Mars has two moons, Phobos and Deimos: Greek for "fear" and "panic".

Mars exploration
Some fly-bys , orbiters and rovers that did and didn't make it to Mars

Only the US, Russia and European Space Agency have had successful missions to Mars.

Orbital alignments creates launch opportunities to Mars every 26 months.

A date with red planet
1960: The world's first Mars mission was Russia's Korabl-4, which fails.

1971: The Soviet Union's Orbiter/Lander Mars-3 becomes the first spacecraft to land on Mars.

1992: The US sends Mars Observer but the spacecraft is lost.

1996: The US launches the Mars Global Surveyor. It also sends Mars Pathfinder, which lands with its robotic rover, Sojourner. Russia sends a spacecraft but it fails.

1998: Japan's spacecraft Nozomi launched but was unable to reach Mars orbit.

2001: The US launches the Mars Odyssey Orbiter, which is working to date.

2003: European Space Agency (ESA) puts Mars Express into the Martian orbit.

2004: The US lands two rovers, Spirit and Opportunity. ESA launches spacecraft Rosetta, which makes a Mars fly-by in 2007.

2005: Mars Reconnaissance Orbiter launched.

2011: The US successfully launches the Mars Science Laboratory and its rover called Curiosity . Russia launches an ambitious mission called Fobos-Grunt aimed to retrieve a sample back to earth from Mars' moon Phobos, and place the Chinese Yinghuo-1 probe in Mars' orbit. China's Yinghuo-1 satellite and Fobos-Grunt finally disintegrated.

Isro's moon mission
India's first mission to the Moon, Chandrayaan-1, was launched on October 22, 2008 from Sriharikota in Andhra Pradesh. The Chandrayaan-1 project cost was ₹386 crore and it carried 11 scientific instruments built in India, USA, UK, Germany, Sweden and Bulgaria. Chandrayaan-1 inserted into lunar orbit on November 8, 2008 and worked for 312 days against the planned two years. Among its achievements was the discovery of the presence of water molecules in lunar soil. Work on Chandrayaan-2 is scheduled to be ready for launch in 2016.

NASA's Curiosity
Curiosity is a robotic rover exploring the Gale Crater on Mars as part of NASA's Mars Science Laboratory Mission (MSL). It was launched from Cape Canaveral on November 26, 2011 and successfully landed on Aeolis Palus in Gale Crater on Mars on August 6, 2012. The rover is probing Martian climate and geology to assess whether the Gale Crater ever offered an environment favourable for microbial life and water and planetary habitability for future human exploration. Curiosity's design will serve as the basis for a planned Mars 2020 rover mission.