Comet Siding Spring makes rare close pass by Mars as MOM watches

Comet's journey began a million years ago and covered billions of miles

Indian Space Research Organisation (Isro)’s Mars Orbiter Mission is safe after the comet Siding Spring made a rare close pass with  Mars, 10 times closer to the Red Planet than any comet on record has come to the Earth.

Isro chairman K Radhakrishnan told Business Standard the space agency had tweaked the MOM’s orbit (which Nasa also had done for its satellites so that they would go behind the planet during the most risky part of the flyby).

“All the instruments, including camera on board, of Mars Orbiter were on and they made observation before and after. We need to analyse it now. This is a systematic observation,” said Radhakrishnan, who said MOM is safe and in good health.

“Phew! Experience of a lifetime. Watched the MarsComet SidingSpring whizzing past the planet. I’m in my orbit, safe and sound,” Isro’s Twitter page said.

At the time of the comet’s closest approach, it was just 87,000 miles from Mars. That’s less than half the distance between the Earth and the Moon. Scientists have said the close encounter between the planet and the comet was a once-in-a-million-year event.

Apart from MOM, Nasa’s three Mars orbiters and two rovers and orbiters owned by the European Space Agency have monitored the comet’s approach and fly-by, which may have left Mars engulfed in a cloud of comet dust. All the spacecrafts are safe now.

None of the space research organisations immediately shared what kind of findings they had. However they were relieved that the comet did not impact any of their spacecrafts that were orbiting.

When the comet was discovered in January 2013, Nasa was concerned the speeding dust particles in its  tail might damage  spacecrafts orbiting Mars. Later assessments, however, allayed such concerns.

CNN reported that scientists were not aware of the comet’s movement towards the inner solar system — perhaps the gravity of a passing star bumped it into its million-year orbit. The comet will continue to sail towards the Sun for a few more days before its orbit takes another million-year trip towards the outer solar system.

The comet was named after the Australian observatory that discovered it last year. It is also believed to be a first-time visitor to the inner solar system, having departed the Oort Cloud, located beyond Neptune’s orbit, more than a million years ago.

Comets are believed to be frozen remnants left over from the formation of the solar system some 4.6 billion years ago, according to reports.