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.

Découverte d’un minuscule trou noir tout près de la Terre

Un tout petit trou noir, baptisé par Licorne, a été découvert par des scientifiques de l’université d’Ohio. Situé à 1500 années lumières de la Terre, c’est le plus petit jamais observé et le plus proche de notre planète.

Des scientifiques de l’université d’Ohio ont détecté une licorne. Pas un cheval blanc à tête de bouc et aux pieds fourchus, ni l’animal mignon et tendance à crinière multicolore qu’on retrouve dans les livres d’enfants. Non sérieusement, ils ont découvert un minuscule trou noir, baptisé Licorne, à 1500 années lumières de la Terre.

C’est le plus petit jamais observé et le plus proche de notre planète, selon les chercheurs dont les résultats ont été publiés dans Monthly Notices of the Royal Astronomical Society.

Le fait qu’il ne pèse « que » trois soleils fait également de lui l’un des plus petits trous noirs jamais débusqués. En effet, très peu de trous noirs si « légers » ont été observés dans l’univers, note l’université d’Ohio. Il pourrait également s’agir du « plus petit trou noir de la Voie Lactée jusqu’ici découvert », selon Tharindu Jayasinghe, doctorant à l’université d’Ohio et l’un des auteurs de l’étude.

Cet objet cosmique a été baptisé « Licorne », du nom de la constellation dans la quelle il se trouve.

Cette licorne déforme son étoile

Ce trou noir de petite taille n’a pas été vu directement par les instruments des astrophysiciens : sa présence a été déduite de l’attraction qu’il exerce sur une étoile géante rouge à proximité, lui infligeant une légère déformation.

En effet, les scientifiques ont focalisé sur une étoile dont il était proche, appelée V 7232 Mon et qui paraissait changer régulièrement en luminosité mais aussi… se déformer ! Cela voulait dire pour les chercheurs qu’un objet non loin d’elle avait une influence sur l’étoile. En analysant les images transmises par le télescope TESS de la Nasa, les astronomes ont pu constater que cette déformation ne pouvait être due qu’à un trou noir.

Contrairement à de nombreux trous noirs qui avalent les étoiles environnantes, cette licorne est bien moins gloutonne, se contentant – pour l’heure – de déformer sa voisine.

Grâce aux observations réalisées près de V 7232 Mon, les scientifiques comptent désormais détecter d’autres mini trous noirs. Chaque découverte comme celle-ci leur permet de mieux comprendre la formation et la mort des étoiles dans notre univers.

# le Dauphiné

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.

Super Lune rose : ce qu’il faut savoir sur ce phénomène attendu dans la nuit d’aujourd’hui et demain

Dans la nuit du lundi 26 au mardi 27 avril, la Lune sera plus proche de la Terre que toutes les autres nuits de l’année, ce qui la fera apparaître plus grande que d’habitude.

Ce phénomène ne se produit qu’une à deux fois par an. Mais pourquoi parle-t-on de « super lune » ? Sera-t-elle vraiment rose ? Que faut-il savoir pour bien en profiter ?

Pourquoi parle-t-on de « super lune » ? 

Cet alignement de la Terre, de la Lune et du Soleil est un phénomène astrologique qui doit son nom de « Supermoon » en anglais (super-lune) à l’astrologue américain Richard Nolle qui l’a nommé ainsi en 1979. Depuis le terme est resté, il est notamment repris par la Nasa.

En fait, la lune nous paraîtra plus grande que d’habitude car elle sera plus proche de la Terre. « La distance moyenne entre la Terre et la Lune est de 384 000 km, explique Gilles Dawidowicz, secrétaire général de la Société astronomique de France. La distance minimale de 356 000 km a été atteinte en 2016, un record depuis 1948 et qui ne se reproduira pas avant 2034 ».

La super-lune de 2016 était 30 % plus lumineuse qu’à l’accoutumée. « Là, ce sera moins exceptionnel mais c’est toujours un joli spectacle », prévient le spécialiste. 

À l’œil nu, c’est assez difficile de voir une différence de taille entre une pleine lune et une super lune. Si on mettait deux photos côte à côte, ce serait comme si on avait un citron vert d’un côté et un citron jaune de l’autre.Gilles Dawidowicz

Sera-t-elle vraiment rose ? 

Non, la lune ne sera pas rose

Inutile de chercher la Lune dans l’espoir de la voir prendre une teinte rosée aujourd’hui : elle n’aura pas changé de couleur. L’expression « Lune rose » n’a pas de valeur scientifique.

Il s’agit d’un empreint à une tradition culturelle nord-américaine, vraisemblablement issue des Amérindiens. Des noms de lune étaient appliqués chaque mois lunaire (et non pas au seul jour de la pleine Lune), commençant soit par une nouvelle Lune, soit par une pleine Lune. Depuis les années 1930, ces noms attribués à la Lune ont été repris dans The Old Farmer’s Almanac (« L’Almanach du vieux fermier »), un périodique américain publié depuis le 18è siècle, populaire pour ses prévisions météorologiques ou ses recettes de cuisine. Pour le mois d’avril, l’almanach utilise le surnom de « pleine Lune rose » (qui a été inspiré par la floraison printanière de la plante Phlox subulata).

La Nasa reprend régulièrement ces surnoms dans ses communications officielles, ce qui peut contribuer à entretenir une certaine confusion entre cette tradition culturelle et la réalité scientifique. Le 20 avril, l’agence spatiale a par exemple titré « La prochaine pleine Lune est une ‘Superlune’ rose », pour parler de la pleine Lune du 27 avril.

Comment bien l’observer ? 

Pour s’en mettre plein les mirettes, mieux vaut guetter le coucher ou le lever du Soleil. L’atmosphère terrestre crée un effet loupe sur notre vision de la Lune, idéal pour faire de jolies photos. 

Et pour une observation plus précise, il est conseillé de se doter d’une lunette ou d’un télescope, « un spectacle sans danger », certifie Gilles Dawidowicz.

Mais pour ce dernier, rien ne vaut une éclipse pour un émerveillement total. Notez bien la date : la prochaine éclipse de lune aura lieu le 19 novembre 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.

Elon Musk pockets $ 25 billion in one day

It is good to be a billionaire in new technologies. Tuesday, Jeff Bezos potentially won $ 6 billion and Mark Zuckerberg 3.8 billion … But the prize goes to the boss of Tesla and SpaceX, who touched a jackpot of $ 25 billion.

Billionaires are profiting from the infatuation of investors on the New York Stock Exchange for technology stocks.  

The billionaires in new technologies lived, Tuesday, a rather enriching day … The vaccinations in the United States, the recovery plan in the country or the prospects of an economic recovery have indeed put them back in the saddle. technology stocks on Wall Street.

The Nasdaq, which brings together the main new technology companies in the United States, recovered in the space of a day more than 3.6%, while the trend was rather trending downwards since the beginning of the year . As a result, the potential fortune of the main billionaires has grown considerably.

Jeff Bezos, the boss of Amazon, won 6 billion dollars, Mark Zuckerberg 3.8 billion … But the big winner is Elon Musk . In one day, it touched almost the equivalent of the annual GDP of Iceland or Estonia – a trifle of $ 25.1 billion. According to Bloomberg, his wealth was valued at $ 149 billion at the start of the week, now to $ 174 billion.

A boost from Bitcoin

The boss of SpaceX has mainly benefited from a positive note from an analyst for his brand of electric cars Tesla. Unlike the others, the analyst estimated that the group can achieve earnings per share of $ 12 by 2023, nearly double the current consensus of industry experts.

This note woke up investors. Tesla shares climbed 20% during the day … Elon Musk also took advantage of the craze for the virtual currency Bitcoin, which exceeded the mark of 46,600 euros, and in which he invested nearly 1, $ 5 billion.

Elon Musk is also getting closer to Jeff Bezos to become the richest man on the planet again, a place he had occupied at the beginning of the year . According to Bloomberg, he is now only $ 6 billion from the founder of Amazon.

What is the mission of the Perseverance robot

published by Jules Bercy

NASA’s perseverance rover, which left Cape Canaveral on July 30, 2020, landed safely on the Red Planet, Thursday, February 18, after having traveled 480 million kilometers. A crucial scientific step to try to find out if life existed on Mars

The main objective pursued with this rover is to search for signs of a possible past microbial life on  Mars . If these predecessors – Spirit, Opportunity and Curiosity – have demonstrated that liquid water flowed over the Red Planet and that it once fulfilled the conditions necessary for the development of life, Perseverance will attempt to determine whether it is. actually sheltered.

The rover will collect rock and soil samples, enclose them in tubes, and leave them on the planet’s surface for a return to Earth by 2031. In addition to studying geology, Perseverance’s instruments will allow the testing of various technologies, with a view to a future mission inhabited by humans on Mars. One of the planned experiments is to produce oxygen from carbon dioxide in the atmosphere of the red planet. This oxygen could be used for respiration and fuel.

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.

Perseverance’s landing on Mars in « seven minutes of terror »

Source : NASA

published by Jules Bercy

About seven months after taking off, NASA’s last vehicle, Perseverance, will still have to survive « seven minutes of terror, » as the ultra-perilous maneuver preceding its landing on Mars is dubbed. 

The chosen location, Jezero Crater, is the most dangerous landing site ever attempted. In seven minutes, the rover must go from a speed of 20,000 km / h to zero. 

The landing will take place at 8:55 p.m. GMT Thursday (3:55 p.m. Washington).

-130km: entry into the atmosphere-

Ten minutes before entering the Martian atmosphere, the vessel separated from the cruise stage which supplied it with fuel during the trip. 

It is then only composed of a rear shield, a heat shield at the front, and, caught between the two, the descent stage, connected to the rover itself. 

At about 130km altitude, it enters the atmosphere at a speed of 20,000km / h, causing friction raising the temperature to 1,300 ° C. The heat shield protects the rover from this infernal heat. 

-11km: opening of the parachute-


But the atmosphere is not enough to slow the ship enough, which is still going at 1,500 km / h. 

At about 11km altitude, at an opportune moment calculated according to the distance remaining to the landing place, a huge supersonic parachute 21 meters in diameter, located in the rear shield, is deployed. 

This slows down the ship to about 300 km / h. 

-9km: heat shield released-

20 seconds after opening the parachute, the heat shield is released: the rover it was protecting is exposed for the first time to the Martian atmosphere. 

A whole new technology, called “Terrain Relative Navigation” (TRN), comes into play: the images recorded live by the cameras of the vessel are compared to maps recorded in its system, where the dangerous zones to be avoided are pre-defined. Taking these data into account, the ship decides on the final landing place.

-2km: retro-propelled phase-

At an altitude of around 2km, the rear shield – and its parachute – are dropped. 

The rover is no longer attached to the descent stage, equipped with eight motors pointed downwards, which light up to finish slowing it down. After performing a maneuver to get away from the parachute, the rover ended up descending vertically, right above its landing site.

-20m: separation of the rover-

At about 20m from the ground, it reached a speed of 2.7km / h, slower than that at which a man walks. The rover then descends along the cables thanks to a system of pulleys, during a final fifteen seconds (stage called « skycrane »). 

The vehicle deploys its wheels at this time. When the latter feel the ground, the lines are cut and the descent stage makes a final push to crash as far as possible. 

Because of the transmission delay between Earth and Mars, when the landing will be confirmed by NASA, it will actually have taken place several minutes earlier. 

Source: Orange with NASA