On the occasion of two year completion of the landmark Mars Orbiter Mission (MOM) launch, ISRO organised a technical meet on “Challenging and Rewarding Year of MOM Around the Red Planet” on November 05, 2015 at ISRO Telemetry, Tracking and Command Network (ISTRAC). Shri. A S Kiran Kumar, Chairman, ISRO inaugurated and congratulated the entire team of MOM for its success. He also recalled the announcement of opportunity made by ISRO for utilising the MOM data to encourage and expand the scientific community to access and analyse the data.

During the meet, the challenging operations of MOM around Mars, specifically during solar conjunction which resulted in the communication blackout, were addressed and the future mission plans was also discussed. A brief presentation on Science results and plans for joint studies with international missions was also made during the meet. Scientists and Engineers from various ISRO centers and research institutes in Bangalore attended the meet.

A Glance through the achieved milestones

MOM was launched onboard PSLV-C25 on November 05, 2013 from Satish Dhawan Space Centre, Sriharikota. After Earth-bound Orbit raising manoeuvres, the Trans Mars Injection manoeuvre was successfully conducted on December 01, 2013 to set the course of the spacecraft towards Planet Mars through a Sun-centric trajectory. En-route to Mars, three Trajectory Correction Manoeuvres were carried out on December 11, 2013, June 11, 2014 and September 22, 2014 to achieve the precise path towards Mars Orbit. The spacecraft traversed 667 million kilometres of interplanetary space to reach mar's territory.

Challenges of placing MOM into Mars Orbit were (i) the re-orientation of the spacecraft to align the thrust vector before firing the engines to reduce the velocity (ii) to meet the required power for performing Mars Orbit Insertion from the spacecraft battery as the solar panels were not receiving any sunlight since MOM was in the shadow of Mars (iii) firing the 440 Newton thrust Liquid Engine along with eight smaller liquid engines thereby imparting braking velocity of 1098.7 m/s (iv) termination of the burn when the required braking velocity is achieved and MOM is in Mars orbit (v) execution of all operations autonomously during the communication blackout (i.e., the radio link between MOM and ground station gets blocked by Mars) and (vi) reorientation of spacecraft to point its antenna towards Earth to resume communication.

The most crucial Mars Orbit Insertion (MOI) manoeuvre was successfully carried out on September 24, 2014. The Spacecraft successfully entered into an elliptical orbit of 422 kms by 76,994 kms around planet Mars. With this, ISRO became the fourth space agency to successfully send a spacecraft to Mars orbit. This mission has claimed many firsts to its credit such as (i) unique launch vehicle trajectory and mission concept (ii) first maiden mars mission of a country to succeed (iii) most economical interplanetary mission in the world (iv) paved way for low cost access to deep space and with frugal engineering concepts and (v) shortest project schedule-realised in a record time of 18 months.

The national and international scientific community congratulated on ISRO for attaining the significant achievement in space technology. In view of successful Mars Orbiter Mission, ISRO was awarded with (i) Space Pioneer award of 2015 instituted by National Space Society of USA. (ii) Selected as one of the 25 best inventions of 2014 as listed by American News magazine ‘Time’ and (iii) Indira Gandhi Prize for Peace, Disarmament and Development for the year 2014

ISRO has been continuously monitoring the spacecraft using its Deep Space Network complemented by that of Jet Propulsion Laboratory (JPL) of NASA. MOM has outlived its designed life duration of six months and also completed one year on its Mars Orbit on September 24, 2015.

Observations from MOM during the last one year

MOM went through a communication blackout as a result of solar conjunction from June 2, 2015 to July 2, 2015. Telemetry data was received during most of the conjunction period except for 9 days from 10-18 June, during superior conjunction. MOM was commanded with autonomy features starting from May 18, 2015, which enabled it to survive the communication blackout period without any ground commands or intervention. The spacecraft emerged out of blackout period with auto control of the spacecraft systems successfully. This experience has enabled the mission team to program a spacecraft about one month in advance for all operations.

Data from MOM Scientific Instruments

The first important operation carried out in the Martian phase was to operate all the five payloads (scientific instruments). All the payloads have been operated and tested successfully. Mars Orbiter Spacecraft is now circling the Red Planet in an orbit with a periareion of 311 km and an apoareion of 71,311 km. All the five payloads of MOM are in good health and continue to provide data.

The Mars Colour Camera (MCC) has acquired more than 440 images so far. A Mars Atlas has been released and the same is made available on ISRO website. MCC has achieved almost all the intended goals. It is planned to study temporal variations of features in comparison with older images of the past from other spacecraft and its own images.

The MENCA payload has observed several atomic species in its neutral mass spectrum. Specific studies of altitude variation of theses were made from the data in Dec. 2014, when the observations were made near periareion at low altitude and conditions were favourable. Prominent atomic species noted are with mass units 28, 44; trends with varying altitudes were also discussed. These results will be consolidated for a publication in the near future. The results are also being compared where possible, with the MAVEN data.

The analysis of the TIS payload was also presented during the meet. Since the instrument has an uncooled bolometer as detector, good sensitivity is obtained only during higher temperatures and therefore requires appropriate conditions for observations. This instrument found the variation in temperature during dust storms to be lowered by 10-15 degrees, which was verified using data from Earth based observations also.

The LAP payload had 80 operations so far and hydrogen Lyman Alpha intensity is estimated as a function of altitude. Calibrations with UV stars are to be done, for which the payload team will work out the sensitivity. Besides, the joint analysis of data using multiple payloads was also presented.

The dust patterns around high altitude regions and in Valles (Valleys) were studied and mean height of dust layer was estimated to be ~1.5 km. Albedo using the 1.65 micron studies of the reference channel of Methane sensor for Mars (MSM) was also estimated. Atmospheric optical depth and its variation was also estimated.

Additionally, joint morphological studies using MCC and the high resolution mineralogical data with the NASA CRISM data was also presented, which enables the identification of different compounds like sulphates and ferrous based compounds.

During the meet, a presentation on future challenges and mission plan for the same was also made. Some of the points covered were

Long eclipses of ~500 minutes expected in Feb 2017 due to eclipses occurring in apoareion compared to the <100 minute eclipses which were near periareion so far ;

Maneovering plans for payload operations with appropriate settings for the reaction wheels

Further imaging of the Martian Satellite Deimos

Opportunities for imaging North pole and other specific targets of Mars

This was followed by presentations on individual payloads, and joint activities with NASA undertaken so far

Regular health checks and orbit determination of MOM is also being carried out. The Spacecraft is in good health and continues to work as expected. Scientific analysis of the data being received from the Mars Orbiter spacecraft is in progress.

Also on this memorable occasion, a book "From Fishing Hamlet to Red Planet" was released. This comprehensive compendium traces the evolution of India’s satellite, launch vehicle and application programmes from a historical perspective. It was released by Prof U R Rao, Chairman, PRL Council and former Chairman, ISRO. Dr P V Manoranjan Rao, Chief Editor of the compendium as well as Dr B N Suresh and Mr V P Balagangadharan, Associate Editors, many contributors of the compendium, a galaxy of many pioneers of the Indian Space Programme and a representative from M/s Harper Collins Publishers who have brought out the compendium, were present on the occasion. The e-version of the book is made available on the ISRO Website for free download.