Exploring the Red Planet: The Dawn of Martian Tourism and its Futuristic Landscapes

Yes, it's a matter of the distant future. We are only slowly preparing to return to the Moon as part of the Artemis mission. On the other hand, space tourism flights have recently become very common. There are also ambitious plans for a space hotel that would orbit Earth at a low altitude. Mars is much farther away, and flights in its vicinity are more difficult, but if humans ever manage to get there and establish permanent colonies, the development of Martian tourism could just be a matter of time.

And although the landing sites on Mars will probably be flat plains for practical reasons, perhaps one day it will be possible to land and establish bases near more interesting geological formations. With a bit of imagination, we can already identify a few places that in a few decades or centuries might become popular tourist destinations there.

Olympus Mons is not only the largest of the inactive Martian volcanoes but also the highest peak in the entire Solar System, nearly three times higher than Mount Everest. It sticks out above the average surface level of Mars by more than 21 km, and it has a very extensive base, with an area comparable to the state of Arizona and... the entire territory of Poland. From a geological point of view, it's a huge shield volcano, formed over many years as a result of lava flows down its slopes.

Although so high, it will not necessarily be difficult to climb for future explorers because the average slope of its hillside is only about 5%. The fact that gravity on Mars is lower than on Earth, which might facilitate the expedition to the very summit, is also significant. The volcano is most likely extinct – thanks to space probes, we know that the last eruptions took place tens of millions of years ago.

At the summit of Olympus Mons, there is a vast crater about 85 km wide and 3 km deep. The sinkholes in it could be a rather dangerous (extreme) high-altitude attraction. However, the view from the top is undoubtedly breathtaking. The volcano lies in a region called the Olympus Mons Aureole, crisscrossed with large ridges and rock blocks. Even further stretches the vast panorama of the Martian highlands of Tharsis. Moreover, its peak might protrude above the common dust storms on Mars.

Olympus Mons, although impressive, is not the only volcano in the area. The Tharsis region is the most extensive volcanic highland on Mars. There are huge shield volcanoes here, much larger than the same type of volcanoes on Earth (for example, the Hawaiian volcanoes).

One of them is Alba Mons, a rise "only" about 6.8 km high above the reference level, but with a surface area not much smaller than Olympus Mons. However, what's most interesting, especially from the perspective of space tourism, is its exceptionally shallow slopes, with the steeper side at just 0.5°. Just right for an easy, mountainous walk – of course, with a suitably adjusted oxygen device.

There are a few more large, steeper mountains on the Tharsis highland worthy of climbing. Why are these volcanoes so high? It might be because Mars virtually has no tectonic plates, and gravity is only about 38 percent of Earth's, which allowed its volcanoes to protrude much higher than on Earth.

Mars also has the biggest known canyon. According to NASA specialists, Valles Marineris is 3,000 to 5,000 km long, which is at least four times longer than the Grand Canyon on Earth (about 800 km). It's not entirely known how it was formed. It might be geologically related to the Tharsis highland, and lava moving there through an area full of volcanoes long ago pushed the crust of Mars up, causing it to crack in the nearby areas. Over time, these cracks transformed into a canyon.

In 2012, the Curiosity rover landed on the Red Planet. It soon began its journey across the surface and quickly came across the bed of a stream that once flowed there. Later, it found more evidence of the past presence of liquid water on Mars, studying the bottom of Gale Crater. Then it started climbing the extinct volcano within it, Mount Sharp (Aeolis Mons, about 5.5 km high), and analyzing the characteristics of its geological layers.

An important goal of the Curiosity mission was to investigate whether Gale Crater and Mars, in general, once had conditions favourable for microbiological life. One of Curiosity's most interesting discoveries is the repeated detection of complex organic molecules in this region. The 2018 study results showed that organic compounds are present inside rocks that are 3.5 billion years old.

In addition, they revealed that the concentration of methane in the atmosphere of Mars changes depending on the season. Methane is an element that can be produced both by microbes and geological processes, so it's not at all clear whether it is actually a sign of Martian life. It is worth approaching the subject sceptically.

However, it's hard to imagine that Gale Crater and its surroundings would not become a target for Martian tourists one day. This is a typical impact crater formed several billion years ago. It stretches for about 154 km and, importantly, is located in the vicinity of the Martian equator, where relatively warm, positive temperatures prevail.

Pictures from the THEMIS instrument aboard the 2001 Mars Odyssey orbiter probably revealed something that leads to the interior of the planet. These are entrances to lava tubes on the slopes of the high volcano Arsia Mons in the Tharsis region. The caves are known today as "Seven Sisters", their entrance holes measure from about 100 to over 200 metres, and they themselves can be deeper than typical caves on Earth.

It's possible that beneath the surface of Mars are wider and more complex, forming extensive chambers and a network of corridors. They remind us of similar formations on fantastic globes known to us from novels and movies. What's more, they may have or could have been the habitat of simple life forms that took refuge in them from the unfavourable conditions on the surface of Mars – after it lost a significant part of its atmosphere and cooled down significantly.

Either way, their exploration would be something incredible. Additionally, in many ways quite safe because the interiors of Martian caves should be well protected against micrometeorites, ultraviolet radiation, the effects of increased solar activity, and other high-energy particles that continuously bombard Mars's surface, not very well protected against them due to its weak magnetic field.

One of the stranger places on Mars. There have even been voices that it hides proof of a past UFO disaster, but a much more likely explanation is its natural geological origin: it is simply a huge volcanic deposit covering one-fifth of the United States, formed as a result of massive volcanic eruptions that have occurred hundreds of times over the last 500 million years. Over time, strong winds have sculpted beautiful, imaginative formations in the local rocks.

A completely different category of places to visit on Mars could be those associated with literature and pop culture. For example, the storyline of the novel "The Martian" (and the movie of the same name directed by Ridley Scott) tells of a crewed expedition to this planet as part of the Ares 3 mission. The landing place is a gentle plain called Acidalia Planitia.

In 2015, NASA published several images of the equator and its areas related to the plot of the book and movie. This was made possible by the Mars Reconnaissance Orbiter, which has been orbiting Mars since 2006 and its high-resolution camera, HiRISE. Numerous, beautiful, multicoloured pictures of very different places on Mars photographed by this camera are continuously available online. Those related to "The Martian" can be seen at: http://uahirise.org/martian

Acidalia Planitia also borders the famous Cydonia region. This is seen in photographs taken by the Viking 1 orbiter in 1976, which showed, among other things, the famous 3 km long "Martian face". Although today we know that it is just an optical illusion and pareidolia, the object still stimulates the imagination. It will certainly be an interesting location on the tourist map of Mars someday.

And although a crewed expedition to Mars is still far off, we can already explore something closely related to it, staying on Earth. "The Martian" was partially filmed in the Wadi Rum valley in Jordan, which simulated the Martian landscape.