As to the United States space probes to Mars, a scientist in the Mariner 9 space project said: “Mars has a character all its own. It is not earth-like or moon-like, it is Mars-like.”

What, then, is Mars like? Mariner photographs through color filters show that the soil of Mars is reddish in color. This confirms observations through telescopes on earth that Mars is a “red planet.”

Four major “geological provinces” have been discovered on Mars, with the aid of thousands of pictures beamed back by spacecraft. The first of these regions is a volcanic province in the planet’s western hemisphere. This is an area of at least nine giant volcanoes. These are dominated by gigantic Nix Olympica, 310 miles across at its base; its upper rim is estimated to be more than three times as high as the over-29,000-foot-high Mt. Everest.

Another of these provinces has a very rugged terrain, which includes many canyons. The greatest of these canyons in this region is reported to be ten times the length of the Grand Canyon and about four times as deep. In other words, the gorge is estimated to be 2,500 miles long, and 75 miles wide and nearly four miles deep.

A third region is one that is heavily cratered. This pockmarked area resembles the moon.

The fourth region is a spectacular expanse of stair-step terraces and deep grooves radiating from the south polar region.

It was also found that near the south pole is a small “ice cap” about 200 miles in diameter, even in the height of summer. Some scientists believe that this “ice cap” is not all frozen carbon dioxide (dry ice) but that, in part, it may be frozen water.

What about Mars’ atmosphere? The Soviet Union’s Mars 2 and Mars 3 probes revealed that the planet’s atmosphere is found to be 2,000 times as dry as the earth’s atmosphere, making Mars “a drier planet than observers on earth had expected,” Tass, the Soviet press agency, reported. The atmosphere next to the planet’s surface was found to be mainly carbon dioxide and so thin that it is one hundredth that of the earth’s.

Is there any possibility of liquid water on Mars? Scientists think that there may have been water at one time, since water is viewed as the likely force to carve out canyons and ridges. But man’s knowledge is limited, and other forces might be capable of causing such canyons. In any event, scientists regard it as physically impossible for liquid water to exist on the surface of Mars now. Why? Because the carbon-dioxide atmosphere of Mars is so thin that there is not enough atmospheric pressure to hold water in a liquid state. Thus a drop of water would evaporate instantly.

As for the temperature on Mars, Soviet probes found the planet to have temperatures ranging from 148 degrees F. below zero to 55 degrees F. above zero. The American Mariner 9 probe indicated that temperatures reach 80 degrees F. above zero in early afternoon.

Atmospheric winds on Mars reach speeds of up to 115 miles an hour. During global dust storms, winds are thought to reach a velocity of 300 miles an hour.

As for the controversial “canals” on Mars, in 1895 one astronomer suggested that they were constructed by intelligent beings to carry water from Mars’ polar ice caps to its equatorial deserts. The canals have long remained a riddle. What, then, did Mariner 9 discover? After more than 7,000 television pictures, analyses showed no canals. The mysterious “canals” were an optical illusion. Explained The National Observer of November 25, 1972: “The fierce Martian winds blow light sand and dust over the planet, and, in so doing, uncover and re-cover patches of darker material. That’s enough for someone wanting to find canals to see them.” The canyons on Mars also appear to have contributed to the idea that there were canals on the “red planet.”

But now, what about the prospect of evolved life on Mars? Dr. Rudolph A. Hanel of the Goddard Space Flight Center in Greenbelt, Maryland, one of the Mariner 9 project scientists, said: “We have not seen any sign of life on Mars.”

[Picture on page 10]

RIGHT: A vast chasm about 75 miles wide and 300 miles long, and branching canyons on Mars, based on photo taken by Mariner 9. ABOVE: An artist’s rendering of a narrow section of one of these canyons on Mars, two miles deep. A report said: “Mars is a far more complicated body than we had thought.”