Who is Zhurong, the first Chinese rover to land on Mars?

If on the Red Planet NASA takes center stage with the exploits of its helicopter, China should soon steal the show. In two or three weeks, or even a few days, the Zhurong rover is expected to land on Mars. He is currently aboard the Tianwen-1 probe, which is working to locate the best place to land it.

While all eyes are on the ongoing Perseverance mission and NASA’s Ingenuity helicopter , let’s not forget that China is preparing to land on the Red Planet. In orbit since February 10 around the planet, the  Chinese probe Tianwen-1 is preparing the landing of the Zhurong rover on a date that has not yet been made public but which is believed to be between mid-May and early June. If all goes according to plan, China would become the second country, after the United States, to land a rover on Mars. Note that the former USSR did succeed in landing a rover on the Red Planet in 1971, but the latter only operated for a few tens of seconds (March 3).

In order for the Zhurong rover to land safely in the southern part of Utopia Planitia , a detailed analysis of its landing site is required. Indeed, you should know that the Chinese Space Agency, unlike NASA or ESA , does not have a high resolution map of the planet Mars. Thus, NASA’s MRO orbit (and its Hirise camera) was able to provide very detailed maps, only a few tens of centimeters in resolution, of the Perseverance landing site .well before its launch. The Tianwen-1 probe is currently mapping the region to draw the most detailed maps possible. The goal is to locate the most suitable place to land the rover safely in an environment not too crowded with large rocks and as flat as possible.

An ambitious rover

The approximately 250- kilogram rover is larger than NASA’s Spirit and Opportunity rovers but about a quarter the size of Curiosity and Perseverance. Equipped with six motorized wheels that will allow it to move like a crab, Zhurong will be able to travel up to 200 meters per hour. It carries six instruments, including a laser camera very similar to the ChemCam instrument of the American rover Curiosity. Added to this are optical cameras, a radar to probe the subsoil, a spectrometer , a magnetometer and a meteorological station (measurements of temperature, pressure and windespecially). Its four solar panels will produce the energy necessary for its operation, which is expected to last more or less 90 days. The data will be relayed by the Tianwen-1 orbiter, or even the European Space Agency’s Mars Express probe if China so requests.

Discovery of a tiny black hole very close to Earth

A tiny black hole, named Unicorn, has been discovered by scientists at Ohio University. Located 1,500 light years from Earth, it is the smallest ever observed and the closest to our planet.

Scientists at Ohio University have detected a unicorn. Not a white horse with a goat’s head and split feet, nor the cute and trendy animal with a multicolored mane that one finds in children’s books. No seriously, they discovered a tiny black hole, dubbed the Unicorn, 1,500 light years from Earth.

It is the smallest ever observed and the closest to our planet, according to researchers whose results were published in  Monthly Notices of the Royal Astronomical Society .

The fact that it weighs « only » three suns also makes it one of the smallest black holes ever to be found. Indeed, very few black holes so « light » have been observed in the universe, notes the University of Ohio. It could also be the « smallest black hole in the Milky Way so far discovered, » said Tharindu Jayasinghe, a doctoral student at Ohio University and one of the study’s authors.

This cosmic object was baptized « Unicorn », from the name of the constellation in which it is located.

This unicorn is distorting its star

This small black hole was not seen directly by the instruments of astrophysicists: its presence was deduced from the attraction it exerts on a nearby red giant star, inflicting a slight deformation on it.

Indeed, the scientists focused on a star to which it was close, called V 7232 Mon and which seemed to change regularly in luminosity but also… to deform! This meant for the researchers that an object not far from her had an influence on the star. By analyzing the images transmitted by NASA’s TESS telescope, astronomers were able to observe that this deformation could only be due to a black hole.

Unlike many black holes that swallow the surrounding stars, this unicorn is much less greedy, content – for now – to distort its neighbor.

Thanks to observations made near V 7232 Mon, scientists now expect to detect other mini black holes. Each discovery like this gives them a better understanding of the formation and death of stars in our universe.

Pink Super Moon: what you need to know about this phenomenon expected in the night today and tomorrow

On the night of Monday April 26 to Tuesday April 27, the Moon will be closer to Earth than every other night of the year, making it appear larger than usual.

This phenomenon only occurs once or twice a year. But why do we speak of « super moon »? Will it be really pink? What do you need to know to make the most of it?

Why do we speak of a “super moon”? 

This alignment of the Earth, the Moon and the Sun is an astrological phenomenon which owes its name of « Supermoon » in English (super-moon) to the American astrologer Richard Nolle who named it thus in 1979. Since the term remained, it is notably taken over by NASA.

In fact, the moon will appear larger to us than usual because it will  be closer to the Earth . “The average distance between the Earth and the Moon is 384,000 km,” explains Gilles Dawidowicz, secretary general of the Société astronomique de France. The minimum distance of 356,000 km was reached in 2016, a record since 1948 and which will not happen again until 2034 ”.

The 2016 super moon was 30% brighter than usual. « There, it will be less exceptional but it is still a nice spectacle », warns the specialist. 

With the naked eye, it’s quite difficult to see a difference in size between a full moon and a super moon. If we put two photos side by side, it would be like having a lime on one side and a lemon on the other. Gilles Dawidowicz

Will it be really pink? 

No the moon will not be pink

No need to look for the Moon in the hope of seeing it take on a pinkish hue today: it will not have changed color. The expression « pink moon » has no scientific value.

It is an imprint of a North American cultural tradition, probably stemming from the Amerindians. Moon names were applied each lunar month (not just the full moon day), starting with either a new moon or a full moon. Since the 1930s, these names attributed to the Moon have been used in  The Old Farmer’s Almanac  , an American periodical published since the 18th century, popular for its weather forecasts and cooking recipes. For the month of April, the almanac uses the nickname  « Full Pink Moon »  (which was inspired by the spring flowering of the plant  Phlox subulata ).

NASA regularly uses these nicknames in its official communications, which may contribute to maintaining a certain confusion between this cultural tradition and scientific reality. On April 20, for example, the space agency headlined  “  The Next Full Moon Is A Pink ‘Supermoon’ ,  ” referring to the April 27 Full Moon.

How to observe it well? 

To be full of eyesight, it is better to  watch for the sunset or the sunrise . The Earth’s atmosphere creates a magnifying effect on our vision of the Moon, ideal for taking pretty pictures. 

And for a more precise observation, it is advisable to equip yourself with a telescope or a telescope, « a spectacle without danger », certifies Gilles Dawidowicz.

But for the latter, nothing beats an eclipse for total amazement. Note the date: the next lunar eclipse will take place on November 19, 2021.

What does rain look like on other stars in the solar system?

It doesn’t just rain on Earth. Venus, Jupiter, Saturn or even Titan, Saturn’s largest satellite, also experience showers. What do they look like? Researchers at Harvard University in the United States modeled the drops of these extraterrestrial rains, and compared them to ours …

Illustration of what could be a Martian rain.Nasa

On Earth, it rains water. But on Venus, it tumbles sulfuric acid. The thick atmosphere of Jupiter is traversed by showers of helium or hailstones of ammonia and water mixed together. And on Titan, the largest satellite of Saturn, we can wipe a grain of liquid methane … With their atmospheres varied in composition, pressure, temperature, the planets of the solar system and their satellites offer sometimes very exotic rains. But what do the drops that carry them look like? According to a study conducted by researchers at Harvard University, and published in the Journal of Geophysical Research , they would ultimately be quite similar to ours

20 mm drops on Titan

To reach this conclusion, the American planetologists Kaitlyn Loftus and Robin Wordsworth modeled the formation of these drops according to the characteristics of the atmosphere and the gravitational pull of the planet. First observation: the more massive the star, the smaller the drops. This is understandable: for a drop to detach from the cloud where it forms, it must be sufficiently attracted by the gravitational field of the planet. However, the more massive a star, the more intense this field. Thus, a drop of methane on Titan (0.22 times the Earth’s mass) is twice as large (20 mm maximum) than on Earth, according to the researchers’ simulations. Severity is not the only criterion that matters. This work emphasizes that the size of the drops is also constrained by their fall. Too small, they evaporate before hitting the ground. Too big, they break into several smaller droplets. Applied to the Earth, this means that a drop measures between a tenth of a millimeter and 11 millimeters. This is why the Breton drizzle is so different from the stormy downpour …

The researchers also studied how drops composed only of water would fall on different planets in the solar system. By comparing with the Earth, Mars (when the climatic conditions were compatible with the presence of water), and the gas giants (Jupiter and Saturn), they found that the raindrops behaved in their fall (speed, shape of gout) in a similar way in these atmospheres which have nothing to do with it. As for their size, it would vary from 7 mm on Jupiter to 30 mm on Titan. This remains a modest difference given the difference between these stars. This relative homogeneity could be explained by the fact that the characteristics of the drops are more dependent on molecular interactions within the fluid than on external conditions.https://d-2223262752363715778.ampproject.net/2104022034000/frame.html

Sizes of water drops on different planets. Credits: AGU. Click on it to see in big

Rains of iron or diamonds

 » This work is useful because it will make it possible to include rain and hail in the modeling of the atmospheric circulation of planets , comments for Sciences et Avenir Tristan Guillot, planetologist at the Observatory of the Côte d’Azur, at the origin of the theory of hailstones mixing water and ammonia on Jupiter. However, we saw with the space probe Juno that it is essential to understand the deep atmosphere of Jupiter, and by extension those of all the gas giant planets which do not have They are also valuable a few months before the launch of the James Webb Space Telescope (JWST), scheduled for the end of 2021, and which should observe many exoplanets, many of which are gas giants« By finely analyzing the light coming from these planets orbiting other stars, astrophysicists should be able to deduce the composition, but also the dynamics of their sometimes very exotic atmospheres. » For that, we will need the tools like these models developed by Harvard researchers « ,  concludes Tristan Guillot. When we consider that on certain exoplanets, it could rain iron, or diamonds, we are in fact eager for the JWST to turn to them.

Here’s what will kill all life on Earth in a billion years

The evolution of the Earth does not bode well: the oxygen, so precious to life, will be eliminated from the atmosphere in a billion years due to the lack of photosynthesis. Oxygen was thus only a small parenthesis in the evolution of the Planet.

In 5 to 7 billion years, the Sun will have used up its helium and will turn into a red giant , multiplying its radius by 1,000, and gradually snapping up the Earth in its burning halo. The temperature on the Earth’s surface will then be so high that the oceans will evaporate. But most of the life forms will have been wiped from the surface of the planet long before and this, due to the lack of oxygen , estimates a new study published in Nature Geoscience .

In reality, it is first of all the lack of carbon dioxide that will lead to this cataclysmic scenario. Indeed, as the Earth warms, more and more water vapor will form, which will result in a regular absorption of carbon dioxide, necessary for the photosynthesis of plants. These will then be unable to survive and produce oxygen .  »  The collapse of the oxygen level will be dizzying,  » warns Christopher Reinhard, one of the two authors of the article. In a billion years, the atmosphere will contain only 1% oxygen compared to 20 to 21% today.

Evolution of the concentration of oxygen, methane and CO2 over time.  © Kazumi Ozaki and Christopher Reinhard, Nature Geoscience, 2021
Evolution of the concentration of oxygen, methane and CO 2 over time. © Kazumi Ozaki and Christopher Reinhard,  Nature Geoscience , 2021

A super-rapid oxygen collapse

And the fall will be particularly brutal: according to the researchers’ models , all the oxygen could disappear in less than 10,000 years. At the same time, the methane content in the atmosphere will be multiplied by 10,000.  »  The composition of the atmosphere will then resemble that experienced by the Earth before the Great Oxidation , which occurred around 2.4 billion years ago,  » warns Christopher Reinhard.

The consequences on the biosphere will be catastrophic. Deprived of oxygen, terrestrial and aquatic plants will die, along with all animals that depend on them for their food. The disappearance of oxygen will also cause ozone to disappear , exposing the Earth to ultraviolet radiation from the Sun which will burn marine organisms on the water surface and plants.  »  Then only anaerobic and primitive bacteria will remain , » says Christopher Reinhard.

The disappearance of the ozone layer will result in the death of most living organisms.  © sarayut_sy, Adobe Stock
The disappearance of the ozone layer will result in the death of most living organisms. © sarayut_sy, Adobe Stock

Oxygen, a small parenthesis in the history of the Earth

These predictions roughly match that of a previous study conducted in 2013 (see below) which calculated that the Earth would cease to be habitable between 1.75 and 3.25 billion years ago. The authors estimated that the least resistant plant species (C3 plants) will disappear in 500 million years and that only a few microbes will still survive in 2.8 billion years. Man, for his part, will have disappeared long before all this . Perhaps decimated by a giant asteroid like dinosaurs or a devastating virus.

In the history of the Earth, atmospheric oxygenation will therefore have been only a small parenthesis. If we place the appearance of the Earth at 4.5 billion years and its death at about 5 billion years, we will have had only 3.5 billion years with a sufficient level of oxygen to aerobic life , or one third of earthly existence. In other words, finding a planet in the universe with an atmosphere comparable to ours would be an extraordinary coincidence .

Quelle est la mission du robot Persévérance

Le rover persévérance de la Nasa, parti de Cap Canaveral le 30 juillet 2020 s’est posé sans encombre sur la planète rouge, jeudi 18 février, après avoir parcouru 480 millions de kilomètres. Une étape scientifique cruciale pour tenter de savoir si la vie a existé sur Mars

Le rover persévérance de la NASA qui s’est posé sur Mars jeudi

Le principal objectif poursuivi avec ce rover est la recherche de signes d’une possible vie passée microbienne sur Mars. Si ces prédécesseurs – Spirit, Opportunity et Curiosity – ont permis de démontrer que de l’eau liquide a coulé sur la Planète rouge et qu’elle a autrefois rempli les conditions nécessaires au développement de la vie, Perseverance tentera de déterminer si elle l’a réellement abritée.

Le rover collectera des échantillons de roche et de sol, les enfermera dans des tubes et les laissera à la surface de la planète pour un retour sur Terre d’ici 2031. En plus de l’étude de la géologie, les instruments de Perseverance vont permettre de tester diverses technologies, dans la perspective d’une future mission habitée par des humains sur Mars. Produire de l’oxygène à partir du dioxyde de carbone présent dans l’atmosphère de la planète rouge fait notamment partie des expériences prévues. Cet oxygène pourrait être utilisé pour la respiration et le carburant.

The life of a small second on Earth for man

published by Jules bercy

99.9% of species that lived on earth have now disappeared

The earth is the cradle of humanity. Man reigns supreme there, without anything seeming to be able to stop him. Yet planet earth did not wait for man to begin its history.

Since life appeared, the earth has hosted countless species, which have followed one another for more or less long time. But 99.9% of the species that lived on earth have now disappeared. Some have gradually evolved into other species. Others died suddenly. On average, their passage on earth lasts only a few million years.

If the history of the earth were written in a thousand-page book, life would appear there around page 185. This life would only be represented by single cells for more than 700 pages. Until the explosion of the multicellular species, from pages 870 to 880. The outflow of the waters was only found on page 916.

During this constant transformation, the planet has also undergone 5 major crises including one, 250 million years ago, during which life on earth almost disappeared. This mass extinction has led to the disappearance of 70% of terrestrial species and 96% of marine species. The planet took nearly 10 million years to recover and resume dance of evolution, with its disappearances, and its newcomers like this time the dinosaurs on page 960 of the history of the Earth.

 At the end of the book, the entire history of Homo sapiens from its appearance until today, would be the subject of only a handful of lines, at the very bottom of the very last page. Its presence on earth therefore represents only 0.004% of its very long history. Man has not been around for a long time, but it does not mean to evolve any more.

 All species are at the peak of evolution, and all are perfectly adapted to their natural environment, from the barnacle, firmly anchored on its whale … to the tiny Dik-Dik apparently so fragile but which survives the repeated attacks of eagles , pythons and lions since time immemorial.

There is no indication that the human species should be eternal. Nor even that it will take longer than the others to disappear. The most probable is that its passage on earth represents only a blink of an eye on the scale of the history of its planet.

A derisory duration. Almost… insignificant?

A unique life on one planet

The only planet that shelters living beings, the earth is an oasis of life in the middle of the great cosmic desert

Humans inhabit a planet in their image: special, unique, perfect. The only planet that shelters living beings, the earth is an oasis of life in the middle of the great cosmic desert. But is she really that exceptional?


Man has in fact only a very vague vision of the universe in which he evolves. His scale is so vast and empty, that he called for lack of anything better, « Space ». Far from being deserted, this space is full of a multitude of planets, as diverse as they are varied.
Since there is on average one planet per star in the universe, there are probably over 100 billion planets in the Milky Way alone, and as many in each of the hundreds of billions of other galaxies.


With such a profusion of planets, how could life have evolved only once? Even with ridiculously low odds of occurrence, the universe is probably teeming with life. Especially since this universe is continuously changing.

Every day, 275 million stars and therefore planets are born. As many arrive at the end of their life, and all are in constant motion. Man cannot even identify his own position, which is not fixed. Starting with the orbit of the earth, rushing around its sun at a speed of 100,000 km / h, and of which humans are not even aware. Nor does he perceive that his entire solar system is propelling his galaxy even faster. And finally, his galaxy, like all the others, is itself in motion. And rushes towards the nearest galaxy, Andromeda has the speed of 720,000 km / h.


The man, so superior seems indeed lost in a cosmic ocean in perpetual motion. In this disproportionate universe, doesn’t asserting that it has no life amounts to prolonging a drink in the ocean and concluding that it does not shelter fish?


In the end, humans have no idea of ​​their place in the universe. Are they alone or just insignificant?

The Universe, the infinite and the infinite

What we currently see are not stars but thousands of galaxies.

Human beings have always known that they hold a special place in the universe. Center of the world, jewel of evolution, he raised his eyes to the sky. And then he started exploring. Man discovered that he inhabits one planet among many in the solar system, a small blue dot rotating around its star.

The universe is teeming with stars more notable than the sun, an anonymous spark at the foot of stellar hierarchies.

A planet finally of banal size, orbiting around a rather pale star, which humans have even classified as a yellow dwarf. A ridiculous size alongside the many giants and super giants.

Take the grandiose Eta Carinais for example, a star a million times brighter than the sun, or the majestic Uy scuti 5 billion times larger.

To measure the immense distances between these stars, man had to invent a special unit of length, the one traveled for a year by a particle of light, 10,000 billion kilometers. A light year is therefore one kilometer away, what a kilometer is the size of a virus, and the universe is 80 billion light years.

The stars are incredibly numerous. A single galaxy contains between 100 and 400 billion stars. AND the galaxies themselves are countless. What we currently see are not stars but thousands of galaxies. For the entire visible universe, this represents a total of 400 sextillion stars. A number so important that the human being has difficulty in conceiving it. Yet it is not so hard: there are as many observable stars in the universe as there are drops of water in all the oceans of its planet Earth, or grains of sand on all its beaches and deserts. But this immensity itself only represents the observable universe, this zone beyond which human telescopes cannot see, a very small part of the real universe.

Man lives in the distant suburbs of an innocuous galaxy, lost in a universe so vast that he cannot even conceive of it as a whole.

Faced with these astronomical scales, wouldn’t it be… insignificant?

The Earth spun faster in 2020

The Earth spun faster in 2020, what does that imply?
The Earth spun faster in 2020, – © Nuttapoom Amornpashara – Getty Images

You didn’t realize it, but July 19, 2020 was perhaps the shortest day of your existence! On that date and on 27 other occasions last year, the Earth broke the daily rotational speed record it set in 2005.

Even Earth wanted 2020 to end ASAP. It turned faster in 2020 than since the start of the weather variation measurements, scientists say. It may take a leap second to get back to the exact time.

If it continues, this trend observed in 2020 could lead to removing one second from universal time, which would be a first. On a millennium scale, however, our planet is losing speed.

As reported in LiveScience , 28 days faster than the others (the fastest ever recorded by Earth since 1960) passed in 2020. Researchers were able to calculate that Earth revolved a few milliseconds faster.

Usually Earth is a great timekeeper, according to TimeandDate.com . It rotates once every 86,400 seconds, which is equivalent to 24 hours . Concretely, an average solar day.