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Air & Space (USA): life flourished on Mars in the past

Air & Space (USA): life flourished on Mars in the past 86
© flickr.com, SpaceX

In his new work, published in the International Journal of Astrobiology, Vincenzo Rizzo from the National Research Center in the Italian city of Cosenza asks a provocative question. Why do many scientists do not want to use geological methods to identify biological processes on Mars, while on Earth these methods are widely used?

He points to one case that took place in Germany in 1908. Then a scientist named Ernst Kalkowsky suggested that multilayer hummocks, columns and sheet-like sedimentary rocks, called stromatolites, are biological in nature. Contemporaries did not believe him. But it was later proved that Kalkovsky was right when it became known for what reason stromatolites are formed. And they arise due to the fact that biofilms consisting of cyanobacteria and other microorganisms capture sedimentary deposits. Stromatolites are the oldest evidence of life on Earth since they are at least 3.5 billion years old and still exist in some remote regions, such as Shark Bay in Australia.

In his work, Rizzo follows in the footsteps of Kalkovsky, analyzing images taken on Mars by the rovers Spirit, Optitude, and Curiosity. These images indicate the presence of biological macrostructures such as stromatolites. He believes that unless a different, non-biological explanation is found, removed by the Mars rovers should be considered Martian stromatolites. Rizzo demonstrates a large number of structures that are strikingly similar to terrestrial stromatolites.

Air & Space (USA): life flourished on Mars in the past 87

In principle, I am very doubtful of evidence that is based only on external resemblance or morphology, since the human brain tends to see or fill with familiar images, even where they do not exist. But Rizzo in his analysis is not limited to appearance. He made me realize that if (and this is big if) stromatolites really existed at an early stage in the life of Mars, then they looked exactly like the samples that he found in the images taken by all-terrain vehicles.

Here comes to mind the famous saying of Carl Sagan (Carl Sagan):

“Unusual statements require unusual evidence.”

For each structure that appears as a result of biological processes, there is a certain geochemical or physical process that imitates it. Some of these processes may not be known to us, because they occur on other planets such as Mars. On the other hand, we now know more about Mars than in the past. We know that at the early stage of the history of this planet, there were lakes, and possibly oceans, including in the Gale Crater, where he made his photographs of Curiosity. Organic matter was found in that place, and we know that pieces of rock can get from Earth to Mars (and vice versa), and also that microbes can survive such a journey. What, then, is a more “unusual” statement? What on Mars during the early usable period were such life forms that were similar to terrestrial ones, and which produced similar biogenic structures? Or that Mars has always been and remains a dead planet?

Air & Space (USA): life flourished on Mars in the past 88
© CC BY-SA 4.0, Alicejmichel

One way or another, the bar for applications for the discovery of life on Mars (both in the past and in the present) must be set very high. Even on Earth, it is sometimes difficult to decide whether a particular structure is the result of biological processes. Now we have more opportunities to explore Mars, but we still cannot do what we do on Earth all the time: go out into the street with a magnifying glass or other device, and study this or that mysterious feature.

If in the future we conduct an isotopic analysis of the structures discovered by Rizzo, which are similar to stromatolites, we will be able to obtain new evidence or refutation of their biological origin (life prefers lighter isotopes that we can use for verification). But I have suspicions that this hypothesis will face the same fate as Kalkovsky’s assumption. The final verdict will be issued much later, most likely when Mars will begin to investigate people who arrived there. And I hope they prove him right.

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Space

Why the universe does not fit into science

Why the universe does not fit into science 101
Photo: YouTube

Science can be compared to an artist painting what he has never seen, or to a writer describing other people’s travels: objects that he has never seen, places where he has never been. Sometimes such scientific “arts” turn out to be beautiful and interesting, but most of them will forever remain only theories, because they are beyond human capabilities.

In fact, science has the right only to speculate: how our universe appeared, how old it is, how many stars and other objects it contains.

Universe model

Why the universe does not fit into science 102

How many stars are there in the sky?

With an unarmed eye, a person can see about nine thousand stars in the sky in one cloudless and moonless night. And armed with binoculars or a telescope, much more – up to several million. However, this is much less than their true number in the universe. Indeed, only in our one galaxy (the Milky Way) there are about 400 billion stars. The exact amount, of course, is not known to science. And the visible universe contains about 170 billion galaxies.

It is worth clarifying that scientists can see the universe 46 billion light years deep in all directions. And the visible (observable) universe includes the space accessible to our eyes from the moment of the Big Explosion. In other words, only this (accessible to human perception) space science refers to our universe. Science does not consider everything that follows.

It is believed that there are supposedly a ceptillion (10 to 24 degrees) stars in our universe. These are theoretical calculations based on the approximate size and age of the universe. The origin of the universe is explained by the Big Bang theory. This is why the universe is constantly expanding and the more time passes, the more complex the universe and its components become.

Why the universe does not fit into science 103

It is not entirely correct to consider and perceive this scientific theory “head-on”. Scientists always claim that that explosion was not exactly an explosion, and the point that exploded was not the only one. After all, it was everywhere, because space did not exist then. And in general – everything happened quite differently from what is described in the Big Bang theory, but all other descriptions of the origin of the universe are even more incredible and inaccurate.

Separate but interconnected

That which is beyond the reach of human perception is usually discarded by science, or recognized as non-existent. Recognizing one thing, science does not want to recognize the existence of the other, although everything in our world is interconnected and is not able to exist separately – by itself.

Each object of the universe is a part of it much more than an independent, separate object.

Any person, like any material object of our world, consists of components: organs, cells, molecules, atoms. And each of its constituent parts can represent the whole world. Separate, and at the same time connected with all the others.

However, science, as a rule, perceives all the components of the universe – people, animals, plants, objects, the Earth, the Sun, other planets and stars – as separate subjects, thereby limiting itself.

Why the universe does not fit into science 104

Even what is considered the visible universe, one of the atoms of which could be called our solar system, is not subject to the boundaries of human perception. But perhaps the atom is an exaggeration, and our solar system is not even an atom, but one of its elements!

How, being so far from the truth, can one reason about something with the degree of probability with which science tries to reason about the origin of the universe?

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Space

An unexplained wobble shifts the poles of Mars

An unexplained wobble shifts the poles of Mars 105

The red planet sways from side to side like a whirligig when it loses speed. The new study allowed scientists to notice that the poles of Mars deviate slightly from the axis of rotation of the planet. On average, they move 10 cm from the center with a period of 200 days.

Such changes are called the Chandler Oscillations  – after the American astronomer Seth Chandler, who discovered them in 1891. Previously, they were only seen on Earth. It is known that the displacement of the poles of rotation of our planet occurs with a period of 433 days, while the amplitude reaches 15 meters. There is no exact answer why this is happening. It is believed that the fluctuations are influenced by processes in the ocean and the Earth’s atmosphere.

Chandler’s wobbles on Mars are equally perplexing. The authors of the study discovered them by comparing data from 18 years of studying the planet. The information was obtained thanks to three spacecraft that orbit the Red Planet: Mars Odyssey, Mars Reconnaissance Orbiter and Mars Global Surveyor. 

Since Mars has no oceans, it is likely that the Red Planet’s wobbly rotation is due to changes in atmospheric pressure. This is the first explanation that researchers have shared. In the future, there should be new details about the fluctuations that have so interested the scientific community.

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Space

Possible “portals” to distant regions of the Universe found in space

Possible "portals" to distant regions of the Universe found in space 106

Scientists have found in space possible “portals” to distant regions of the universe. They could be some supermassive black holes in the center of galaxies. This is reported by the Monthly Notices of the Royal Society magazine. In theory, a spaceship can pass through such portals.

Russian scientists have found that black holes in very bright galaxies may be the entrances to these “portals” or “wormholes”. In theory, a spaceship can pass through such portals. However, they are surrounded by intense radiation, which negates the crew’s chances of survival.

The similarity between a wormhole and a black hole is that they have extremely strong gravity. However, as scientists believe, the body cannot get out of the black hole, falling beyond the event horizon, while the “wormhole” must have an exit somewhere else in space.

Possible "portals" to distant regions of the Universe found in space 107
Photo: 
NASA

So, experts say, the collision of two bodies inside a wormhole in images from space would look like an explosion. That is, the active galactic nucleus (AGN), which seemed to be such earlier, may in fact be the entrance to the “portal”.

Russian physicist Mikhail Piotrovich emphasizes that scientists still know little about the internal structure of the “wormhole.” Moreover, they are not even sure that such a phenomenon exists at all. In addition, the closest object similar to it is 13 million light-years away, so humans are unlikely to be able to reach it in the foreseeable future.

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