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ISRO successfully test-fires Mars orbiter’s main engine
Shubhadeep Choudhury
Tribune News Service

Bangalore, September 22
Indian Space Research Organisation (ISRO) scientists today successfully reignited the Mars Orbiter Mission (MOM) spacecraft’s main engine for four seconds.

“Test firing successful! We had a perfect burn for 4 seconds as programmed. The trajectory has been corrected. MOM will now go ahead with the nominal plan for Mars orbit insertion,” ISRO posted on the Facebook page of MOM. The satellite, which has been on a nine-month journey to Mars, has been reignited by ISRO’s Mars Mission team as a trial before its final firing to the Red Planet’s orbit on Wednesday.

The burn of the 440 Newton engine had started at 14-30 hours and lasted for 3.968 seconds. But the signal carrying the result of the test-firing reached the ground control 12 minutes later.

Located now around 215 million (over 2 crore) km away from Earth, communication between MOM and the ground control takes 12 minutes each way. The burn on Wednesday will be for 24.14 minutes. About 250 kg propellant will be consumed during the burn, which will be the last operation of the main engine. Any future requirement such as orbit raising of the spacecraft or its attitude control will be taken care of by the eight 22 Newton thrusters installed in the spacecraft as back-up engines.The main engine was last fired on December 1, 2013, to free the spacecraft from Earth’s gravitational pull (Earth’s sphere of influence or Earth’s SOI) and push it into a trajectory to reach the SOI of Mars.

The spacecraft reached the SOI of Mars today around 6 am. Since leaving the SOI of Earth on December 1, the spacecraft has travelled for 300 days through a heliocentric path without the aid of any engine. On three occasions, course correction of the spacecraft was required and these were done with the help of the thrusters.

Spacecraft to enter Red Planet’s orbit tomorrow

* The Mars Orbiter Mission spacecraft’s main engine was reignited for four seconds

* The test was a trial before the satellite’s final firing to the red planet’s orbit on Wednesday

* The engine, last fired on December 1 last year, was lying idle for the past 300 days

NASA’s Maven lands in

London: NASA's latest Mars satellite, Maven, has finally landed in the orbit above the planet successfully. Principal investigator Bruce Jakosky said though previous spacecraft had helped them “learn a lot about the upper-atmosphere, they hadn't been able to put a complete picture together yet,” the BBC reported. — ANI