“Since ancient times, we earthlings have believed that ‘Mars’, the mysterious red planet carried war, pestilence and the need for human sacrifice. The Romans named ‘Mars’ as their ‘God of war’. The mystery possessed by this planet has always incited the curiosity of earthlings with an imaginary belief that there also exists an alien civilization like on earth. Several movies fed on this idea, in which green Martians with peculiar head and dressing, seen trying to take over the earth”.
Until the sixties, the conception of tellurians was up to the movies, picturization, or up to what the scientists could see through a telescope, etc. Then began the space race and ‘Mars’ became the favorite target for scientists’ curiosity. The beginning of the space research era helped mankind in exploring the hidden secrets of the universe. The USA and the erstwhile USSR pioneered space exploration with several of their space crafts and satellites sent on expeditions to study the Earth’s atmosphere, weather, oceans as well as Sun and other celestial bodies and planets like Moon, etc. All such expeditions brought back invaluable information about the evolution and history of the earth, moon, and other planets and celestial bodies.
`Mars’ and the earth has an almost equal rotational period at the axis. Mars takes 24 hours, 37 minutes, rotating upon its axis, thus the Mars day is identical to an earth day. While earth takes approximately 365 days to rotate around the sun, Mars takes 687 days to make such one trip, because of its eccentric orbit. The gravity of Mars is one-third of the earth’s, and the atmosphere at Mars is much thinner than that at the earth, as such the atmospheric pressure at ‘Mars’ is just 1% that of earth.
Exploring the mystery of Mars
1. In 1962, the erstwhile USSR launched Mars 1, successfully left Earth’s orbit but failed as the communication with the craft was lost en route.
2. The USA’s craft Mariner-3 launched in 1964, was also failed when its solar panels could not be opened.
3. The same year USA launched another spacecraft Marine-4 that sent 22 close photographs of ‘Mars’ showing therein a cratered, desert surface.
4. the USA again launched Mariner-6 in 1969, which passed within 3400 km of the planet and sent video of the equatorial regions as well as surface temperature and atmospheric pressure measurements of the planet.
5. the USA launched again Mariner-7 in the same year of 1969 that passed over the Southern hemisphere and sent back about 200 photographs. So far all the Mariners launched by the USA were flybys and none were meant to land at the surface of the planet.
6. In 1971, USSR launched an orbiter/lander Mars-2, but it crashed during a dust storm.
7. Again in the same year USSR launched Mars-3 that made the first successful landing on Mars, transmitted 20 seconds of data until contact was lost in dust storms.
8. The USA’s Mariner-9, launched in 1971, became the first US spacecraft to orbit ‘Mars’. It sent back the first high-resolution images of Martian Moons Phobos and Deimos. The Mariner-9’s important discovery was the presence of huge volcanoes on Mars, larger than any in the solar system, so far known. The Mariner-9 also recorded hydrogen escaping the planet in such a huge amount, which indicates that thousands of gallons of water evaporating a day. Mariner-9 also found that the atmosphere of Mars is 100 times thinner than that of earth, composed mainly of carbon-di-oxide, carbon monoxide, water vapors, and a little oxygen. During this period, USSR also sent three more spacecraft. Mars-4 in 1973, Mars-6 in the same year, and Mars 7 again in 1973, but none was succeeded due to one or more technical reasons.
9. Viking-I and Viking-11 by the USA
In 1976, the Viking-I and Viking-II spacecraft sent by the USA were more successful. Viking-I became the first US orbiter to have landed on Mars. It returned thousands of images and discovered the presence of water ice in the polar cap. While Viking-II, sent in the same year, detected the presence of Argon and Nitrogen in the atmosphere of Mars. It also sent thousands of images and found the sky of Mars, blue, and soil red, and rocks greyish green and black in color. Scientists who analyzed data received from Viking opined that though Mars would have lost much of its water, it still has plenty in frozen form and Mars is much colder than the earth. The average temperature on Mars was found to be below the freezing point of water.
None of the Viking scientists could opine about the existence of life on Mars. Scientists concluded that more ultraviolet light reaches the Martian surface than the earth because the earth’s ozone shield blocks much of the ultraviolet rays. Viking’s striking color photographs proved beyond doubt that the planet is strikingly red and its dust, rocks, and boulders are of varying shaded colors. In 1977, an orbiter passed within 90 km of Phobos, one of the moons of Mars, and sent close pictures in routine, revealed that both the moons are of potato shape rather than spherical and have no identical color to Mars. After these two Viking missions of the USA, the USSR launched Phobos I-orbiter/ lander in 1988 to investigate the moon Phobos, but again the mission failed due to a bad command that caused the spacecraft to point its solar panels away from the sun. The USA again sent Mars observer in 1992, to conduct high and low-resolution imaging of the planet, surface investigation, and weather analysis, but on Aug. 21, 1993, lost its communication to the earth just before it could enter into the orbit of Mars. One thing the Viking mission could not achieve was movement, although it had robotic arms that could reach out and scoop up the soil.
10. The spacecraft Pathfinder, launched from Cape Canaveral on Dec. 4, 1996, landed on Mars on July 4, 1997, after concluding a 5000 km. journey. Pathfinder sent back detailed photographs of a harsh landscape that bears signs of availability of water, a basic requirement for life. The Pathfinder and its rover Sojourner provided a wealth of information on the rocks, soils, and atmosphere on Mars. It returned the first live pictures of the planet’s topography and its tiny rover explored a variety of rocks and analyzed their mineral composition with its cameras and on boards, X-ray spectrometer analysis indicated the presence of oxidized iron and rusting of the surface of Mars. Images and various data sent by Pathfinder gave the strongest evidence that the Red Planet had an abundance of water millions of years ago. NASA launched the Mars global surveyor on Nov. 7, 1996, the spacecraft began its mapping operations on March 27, 1998, discovered clear proof of an ancient hydrothermal system near the equator, which means that a thicker atmosphere had existed on Mars history.
11. The rovers though sent very important information to the earth, yet it did not have many scientific instruments with it and can’t move far from its lander. The latest MER robots sent on Mars was designed as robotic geologists. The instruments and equipment packed into the rovers were primarily designed to investigate the rocks. It is a much larger vehicle, more than 180 kg in weight and able to travel tens of meters every day, and carries an entire set of scientific instruments with it.
We don’t know so far, when could we able to send a human being to Mars. The failures of various missions sent to Mars, the huge cost involves in sending space crafts, are some of the reasons for hesitations in sending human beings at present. So nothings like this have ever been attempted and it would take several test missions to prove the concept.
The quest for knowing the mystery of ‘Mars’ is insatiable so far, yet the quest is going on each mission, brings to us more and more information and varied knowledge about this red planet, and we hope to find more surprises on Mars in the times to come.