Xplore Space Magazine Vol. 2 - On To Mars, The Next Giant Leap

The Pioneers Early unmanned Mars probes This magazine is about the future exploration and eventual settlement of the planet Mars. But whilst we talk about sending humans to the Red Planet in the future, let us not forget those early robotic missions that allowed this to be possible. The first article in this magazine is therefore dedicated to those early explorers that gave us the knowledge we now have of Mars.

The first Mars probes were Soviet, part of the USSR's Mars Program. They had truly the worst spacecraft names in history; 1M No. 1, 1M No. 2, 2MV-4 No. 1, Mars 1, and 2MV-3 No. 1. They also all failed, but to their credit it was the rockets launching them that exploded, not the probes themselves.

The first series of successful expeditions were the American Mariners. Mariner 3 failed at launch, but Mariner 4 performed the first ever flyby of the Red planet on the 15th of July, 1965. Unfortunately, in doing so it proved once and for all that Mars was not the alien-inhabited world that most people had imagined, but rather a dead wasteland, which seriously depressed a great many space enthusiasts. It wouldn't be until decades later that scientists would realise Mars may have had life-harbouring conditions after all in the distant past.

Nevertheless, Mariners 6 and 7 undeterred by either this or the failure of the recent Zond 2 and 2M No. 521 Soviet Mars probes, successfully performed more flybys of the planet in July of 1969, only days after Neil and Buzz took the most famous steps in history.

Mariner 8 was meant to be the first spacecraft to enter orbit of Mars, but unfortunately it never made it there, as its rocket failed just after launch and it fell into the Atlantic. Mariner 9 had more success, becoming the first probe to orbit Mars. Then, the Soviets would again try to beat the West, and this time, their luck turned around. Not by much though. The 3MS No. 170 probe still failed like all the others, but the not quite as unromantically named Mars 2 and 3 did not. Both of them entered Martian orbit in late 1971, and both tried to deploy small landers.

Alas, it was here that their luck ran out. When they arrived a large global dust storm was encircling the planet, and the probes expended a large amount of their film snapping photos of featureless dust clouds. Their landers didn't do much better. Mars 2's lander entered the atmosphere too steeply and failed to deploy its parachute in time, impacting the surface. Mars 3's lander was able to land successfully, but the sandstorm quickly built up enough static charge on the small metal frame of the lander to fry its transmitter after spending just 20 seconds on the surface, and unsurprisingly all subsequent attempts to reestablish contact with either of them failed.

Attached to the sides of the Mars 2 and 3 landers were small ‘Prop-M’ rovers. Mars 2's was destroyed when the probe hit the surface, but whether Mars 3's successfully deployed is unknown. Even if it had deployed, it would have had no way of contacting Earth, and any data from it would have still been lost. The Soviets kept trying with the Mars 4, 5, 6, and 7 probes, but all of them except for five, which operated in Martian orbit for 9 days, failed.

Despite their best efforts, the Soviet Mars program simply never managed to break free of their constant failures, in stark contrast to their extraordinary achievements in launching the first satellites and humans into orbit. The first age of Martian exploration ended as Mars 7 swung past the Red Planet, its lander having missed the atmosphere and been doomed to fly though deep space for all eternity.

The story of next probes to endure the long journey to Mars would be very different, and much more successful.

The vikings were about to invade Mars.

NASA's Viking 1 launched in mid 1975, followed shortly by Viking 2 a few months later. Reaching Mars in 1976, they both snapped pictures of its surface, sending back data for many years to come. As well as a suite of orbital instruments, the Vikings also carried landers, like the soviet Mars probes had. These ones however, to everyones relief, actually worked.

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