‘Probe in good health and has to travel 490 million km more’ The Mars Orbiter spacecraft completes 100 days in space on Wednesday (Feb. 12), or roughly a third of its journey towards the Red Planet. The country’s first interplanetary probe, launched on November 5, 2013, is in good health during its curved travel of 190 million km so far towards Mars; it has to traverse a total of 680 million km over the next 210 days, Indian Space Research Organisation said. The ground station of ISRO Telemetry, Tracking and Command Network (ISTRAC) monitors it continuously from Byalalu on the outskirts of Bangalore. Signals from the spacecraft now take almost a minute each way. Although the orbiter has travelled 160 million km in a semicircular path, it is 16 million km away from Earth if an imaginary straight line is drawn between the two because Earth is also moving in the same direction, an official explained. On February 6, all the five instruments on the Mars orbiter were switched on for tests and were found to be performing well. “Except for a 40-minute break in the telemetry data received from the spacecraft to the ground station, data has been continuously available for all the 100 days. At Pagespresent, the spacecraft is at a radio distance of 16 million km [from Earth] causing a one-way communication delay of about 55 seconds,” ISRO said. The spacecraft is scheduled to be near the Red Planet around mid-September after travelling nearly 300 days. Meanwhile, using the pre-set propulsion system, ISTRAC is due to do a few course corrections as the orbiter covers the remaining 490 million km. Three more such `trajectory correction manouevres’ are slated for April, August and September. Then the spacecraft will be inserted into an orbit around Mars by an operation called `Mars orbit insertion’ on September 24.