The supplementary burn made this morning to correct for the incompleteness of the 4th burn yesterday appears to have been successful. The objective was to reach an orbit (apogee) of 100,000 km and this seems to have been achieved with some margin to spare. The observed change is to an orbit with an apogee of 118,462 km. The next step on 18th November is to raise the apogee to just under 200,000 km and then insert the craft into the Trans-Mars trajectory on 1st December.
So far, so good and the success of the correction by the supplementary burn is both impressive and encouraging.
- Fourth supplementary orbit raising manoeuvre of Mars Orbiter Spacecraft, starting at 05:03:50 hrs(IST) on Nov 12, 2013, with a burn Time of 303.8 seconds has been successfully completed.The observed change in Apogee is from 78276km to 118642km.
The launch and subsequent orbit manoeuvre burns so far are summarised here:
- The Mars Orbiter Spacecraft, India’s first interplanetary spacecraft, was launched into an elliptical earth orbit with a perigee of 248.4 km and an apogee of 23,550 km, inclined at an angle of 19.27 deg to the equator by India’s Polar Satellite Launch Vehicle in its twenty fifth flight (PSLV-C25). The achieved orbit was very close to the intended one. The launch was conducted from Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota on November 05, 2013. The launch of Mars Orbiter Spacecraft occurred as scheduled from the First Launch Pad at 2:38 pm IST after a fifty six and a half hour count down.
- The first orbit-raising manoeuvre of India’s Mars Orbiter Spacecraft was performed at 01:17 hrs Indian Standard Time (IST) early this morning (November 07, 2013) when the 440 Newton Liquid Engine of the spacecraft was fired for 416 seconds by commanding it from Spacecraft Control Centre (SCC) at ISRO Telemetry, Tracking and Command Network (ISTRAC) at Peenya, Bangalore. With this engine firing, the spacecraft’s apogee (farthest point to Earth) has been raised to 28,825 km, while its perigee (nearest point to Earth) is at 252 km.
- The second orbit raising manoeuvre of Mars Orbiter Spacecraft, starting at 02:18:51 hrs(IST) on Nov 08, 2013, with a burn time of 570.6 seconds has been successfully completed.The observed change in Apogee is from 28814 km to 40186 km.
- The third orbit raising manoeuvre of Mars Orbiter Spacecraft, starting at 02:10:43 hrs(IST) on Nov 09, 2013, with a burn time of 707 seconds has been successfully completed.The observed change in Apogee is from 40186km to 71636km.
- In the fourth orbit-raising operation conducted on Nov 11, 2013, the apogee (farthest point to Earth) of Mars Orbiter Spacecraft was raised from 71,623 km to 78,276 km by imparting an incremental velocity of 35 metres/second (as against 130 metres/second originally planned to raise apogee to about 100,000 [1 lakh] km). The spacecraft is in normal health. A supplementary orbit-raising operation is planned for November 12, 2013, at 0500 hrs IST to raise the apogee to nearly 1 lakh km.
Related posts:
Indian Mars orbiter’s fourth burn in earth orbit only partially succesful
India’s frugal Mars orbiter mission completes 3rd burn in earth orbit
Frugal engineering for India’s Mars mission
Tags: India, ISRO, Mangalyaan, Mars, Mars Orbiter Mission