Will India be able to lower its spacecraft into the Martian orbit in its debut attempt? The answer will be available around 8.15 a.m. on September 24.
“We have left no stone unturned to ensure that this happens,” said S. Arunan, Project Director, Mars Orbiter Mission (MOM), Indian Space Research Organisation (ISRO).
On Wednesday, the orbiter’s propulsion system, called 440 Newton engine or the Liquid Apogee Motor (LAM), will erupt into life at 7.17 a.m. after remaining dormant for 300 days during the spacecraft’s journey to the Red Planet.
Simultaneously, eight 22 Newton thrusters on the spacecraft will pounce into life. The LAM and the eight thrusters will fire together for 24 minutes to perform the MOM’s most crucial manoeuvre called Mars Orbit Insertion (MOI) to lower India’s spacecraft into the Martian orbit, with a peri-apsis of 423 km and an apo-apsis of 80,000 km. The manoeuvre will end at 7.41 a.m. Around 8.15 a.m., the world will know whether India is home and dry.
“Both the hardware and software simulation has been well-established for the MOI. We do not expect any new concern to crop up for the MOM success,” said Mr. Arunan.
ISRO wanted to ensure that the LAM would ignite into life after it had remained dormant for 300 days. Towards that, ISRO tested the LAM on the ground, simulating the thermo-dynamic conditions of the Mars spacecraft, he said.
A test-firing of the LAM and eight small thrusters was done simultaneously. “We have conducted this test in the operating conditions [of the spacecraft] as envisaged during the MOI manoeuvre. The test was successful. The engine performance was as per prediction… So there was no concern on the simultaneous firing of the LAM engine and 22 Newton engines,” Mr. Arunan asserted.
Besides, ISRO test-fired a LAM, kept on the ground for 450 days in the same conditions that India’s Mars orbiter was undergoing in space now. “We kept it in a vacuum chamber for 450 days and when we fired it again, its performance was absolutely as predicted,” Mr. Arunan said. All the tests were done at the ISRO Propulsion Complex, Mahendragiri, Tamil Nadu.
V. Kesava Raju, Mission Director, MOM, said the spacecraft’s velocity would be reduced on September 24 to enable it to get the Martian orbit.
“When India’s spacecraft comes under the influence of Mars’ gravity on that day, it reaches the closest point to Mars. At that time, our spacecraft will attain a velocity of 5.7 km per second…But we require only 4.6 km a second. So the spacecraft’s velocity is reduced by 1.1 km so that the spacecraft can be contained in the orbit around Mars,” Mr. Kesava Raju said.The test-firing of the propulsion engine on India's spacecraft to Mars for four seconds on Monday went off smoothly, boosting the hopes of the Indian Space Research Organisation (ISRO) engineers about the engine's performance on Wednesday when it will fire for 24 minutes to insert the Mars orbiter into the Red Planet's orbit.
The firing of ISRO's propulsion engine, called 440 Newton engine or Liquid Apogee Motor, on board ISRO's Mars orbiter began at 2.30 p.m. on Monday and there was no hitch at all in its performance. The firing helped to correct the trajectory of the orbiter - the altitude of the spacecraft was brought down by 200 km.
The engine ignited after it had slumbered in space for 300 days during the spacecraft's voyage to the moon. The LAM engine was fired last on December 1, 2013 to catapult India's Mars orbiter from its earth-orbit into sun-centric orbit and its sojourn to Mars began.
No comments:
Post a Comment