The sky was still quite bright. The northern hemisphere of Mars is now in the late summer and early autumn season, so it is not yet 6 o'clock in the afternoon, and the sky is still quite bright.

The seasons of Mars and the Earth's seasons are the same, because the tilt of the axis of rotation of Mars and the tilt of the Earth's axis of rotation are almost the same, so there are also four seasons on Mars. It's just that Mars has an orbital period of 687 Earth days, so the length of a season on Mars is basically twice as long as each season on Earth.

It was for this reason that Tang Feng saw the huge cave in the wheelhouse of the "Exploration" far away.

The cave was terrifying from a distance, a large black patch, definitely more than a hundred meters in diameter, and it appeared so abruptly on the flat Tarsis Plateau.

At night, if Tang Feng is not careful, he may drive the "Discovery" rover into this huge cave, like a rabbit falling into a trap dug by a hunter.

These caves were observed by geoscientists several years ago through the Odyssey probe. There were seven in total, all of which were located on the east side of the Alsia volcano, and the cave closest to the "Kunpeng", which Tang Feng saw now, was only 600 meters away from the landing site in a straight line.

These seven caves are also one of the key sites to explore after the landing on Mars, because according to scientists' observations, some methane gas will be ejected from these caves regularly after the Martian equatorial temperature rises in summer. It is the presence of these methane gases that has led to great interest in the seven caves among geoscientists.

As we all know, in the solar system, methane is almost synonymous with life. Although it is said that where there is methane, there will not necessarily be life, but where there is life, there must be methane.

Because there is a lot of methane in the products of anaerobic decomposition of organic matter, methane can also be synthesized into organic matter in a specific situation. And for life to exist, there must be organic matter. So, if there is methane on some planets, there may be organic matter, and then there may be life.

And on Mars, the presence of water has been confirmed. Although the climate of Mars is more extreme, there is water and methane, so there is a great possibility of organic life. In the South Pole of the Earth, the climate in winter is also quite extreme, but in the South Pole, there is still life.

It is for this reason that these seven caves have been designated as the key sites to be explored after this landing on Mars. And even if no life can be found in these seven caves, then with the natural conditions of these seven caves, maybe with a little modification, it can become an excellent site for the construction of a Martian advance base.

Mars is a perennial sandstorm, especially the kind of super sandstorm that sweeps across Mars. Building a Mars forward base on the surface of Mars will inevitably be tested by those super dust storms. And if the conditions of these caves are suitable, and the advance base is set up in these caves, then no matter how powerful those super sandstorms are, I am afraid they will not be able to help the advance base underground.

Tang Feng parked the "Discovery" rover at the edge of this cave, put on a helmet and got out of the car. This new type of extravehicular Mars spacesuit, which weighs only more than 40 kilograms on Earth, is now worn on the body and carried on Mars, which is almost equivalent to carrying 15 kilograms on Earth. With Tang Feng's physical fitness, which is comparable to that of a demonic beast, this weight is naturally nothing.

Tang Feng held a large HID xenon strong flashlight in his hand, and carefully stood at the edge of the cave to shine downward, and the strong wind gushing out of the cave made Tang Feng also can't help but shake his body a little. And this kind of strong wind gushing out from time to time also made Tang Feng happy.

Since there would be such a strong underground wind, it is enough to show that the depth of this cave is deep enough, otherwise it would not have produced such a strong wind. And with such strong winds, it is clear that the cave was not caused by a meteorite impact, but was formed by the movement of the earth's crust during the ancient period of Mars, or simply an ancient volcanic magma channel

This special HID xenon strong light flashlight has strong penetration and brightness, don't look at it as just a flashlight, but its brightness will not fall behind at all compared with the headlights in front of the train. Therefore, under the illumination of the flashlight, Tang Feng finally saw the situation in this cave clearly.

To Tang Feng's surprise, this cave is not a bottomless cave like the one he imagined, but a cave that extends diagonally downward, and the further down, the width of the cave seems to be larger, but the cave is too deep, even with the irradiation distance of this special flashlight, it is impossible to see what it looks like inside.

The entrance to this cave is roughly circular in shape, with a diameter of about 100 meters. After about ten meters of vertical descent from the entrance of the cave, the cave extends diagonally downward in the form of a forty-five degree angle, and the further down it goes, the wider the cave becomes.

After about a hundred meters, because of the angle and flashlight, you can't see the situation below. However, based on the strong winds gushing out of the cave entrance, Tang Feng estimated that the depth of this cave should be enough to make people marvel.

After thinking about it, Tang Feng decided to go down and have a look. In fact, it is basically the same anywhere on the surface of Mars, so no matter where the Mars advance base is built on the surface of Mars, it will not be able to avoid the invasion of that super sandstorm. And since this cave is not the kind of vertical cave that goes straight up and down, it already has the conditions for building an advance base.

Although after the Star Core Split completely controls Mars, Tang Feng can open up a giant cave with better conditions on any mountain to use as a base for advancement, but that will not be implemented until the Star Core Split completely controls Mars. It took more than half a month for the star core to control the small moon at the beginning, and who knows how long it will take to control Mars? Maybe when Tang Feng and the others return to Earth, the Star Core Split may not be able to complete this task.

After thinking about it, Tang Feng still decided to choose the location of the forward base here for the time being. Of course, whether this cave can be a qualified base for advancement still needs to be carefully investigated.

Tang Feng has always been a person who wants to do it. Just as they said they were out to inspect the location, so let's go down and investigate it now!

He took out the static rope from the "Exploration" and fixed it to the towing hook of the "Exploration", and then Tang Feng followed the rope and quickly landed down the cave. (To be continued.) )