On the computer screen, a shadow appeared. Painted in fake colors and greatly enlarged, it transcribes a microscopic rock debris attached to the end of a long tungsten point. “This image shows the internal molecular composition of one of the grains that we studied”, says Rosario Brunetto, in the darkness of an experiment room of the Soleil synchrotron, in Gif-sur-Yvette, in Essonne. CNRS manager of the “Astrochemistry and origins” team at the nearby Institute of Space Astrophysics (IAS), in Orsay, he is one of the twenty French scientists from seven laboratories who are involved, in parallel with 250 of their foreign colleagues, in the preliminary analyzes of samples from the asteroid Ryugu.

Brought back at the end of 2020 by the Hayabusa-2 probe of the Japan Space Exploration Agency, JAXA, these 5.4 grams of ultra-cool extraterrestrial material and – unlike meteorites – not altered by a passage in the atmosphere, are highly coveted by cosmochemists for what they could learn about the origins of the Solar System. “Indeed, Ryugu belongs to a category of carbonaceous rocky bodies which, it is believed, has changed little since their formation in the primitive protoplanetary disc, 4.5 billion years ago”, explains Rosario Brunetto after having prepared his Raman microscope for the detailed observation of the infinitesimal stony inclusion, the size of a bacterium, that can be seen on the monitor. ?Ryugu could have kept a composition of minerals and organic molecules close to what he had at the beginning. ť

Sorted, weighed, cataloged

Ryugu is above all – with the exception of Itokawa, of which only 3,000 micrometric grains were delivered in 2010 by the Hayabusa-1 mission – the only asteroid from which a spacecraft has so far managed to bring back fragments. Collected in February and July 2019 on the surface of this small near-Earth star barely 1,000 meters in diameter (at the level of the equator), they arrived on Earth, in the Woomera Desert in Australia, on board of a capsule during the night of December 5 to 6, 2020. They were immediately transported to a JAXA institute located in Sagamihara, not far from Tokyo. Since then, they have been sorted, weighed, pre-characterized and cataloged, under vacuum or under a nitrogen atmosphere, in a so-called ?curation? facility, ie conservation.

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Sorted, weighed, cataloged

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The flight is again postponed. Boeing announced Tuesday, August 3, delaying the unmanned test mission of its Starliner space capsule to the International Space Station (ISS) because of a problem in the propulsion system, postponing an important test for the company, whose first attempt had failed in 2019.

The spacecraft was scheduled to launch into space from Cape Canaveral, Florida, at 1:20 p.m. (7:20 p.m. in Paris), aboard an Atlas V rocket built by the United Launch Alliance consortium. But nearly 2 hours before launch, Boeing announced on Twitter that the flight was canceled.

According to a NASA statement, the mission was not canceled due to the capricious weather, but due to “Unexpected indications on the position of the valves of the Starliner propulsion system”, with the next possible window for launch being Wednesday at 12:57 p.m. (16:57 GMT).

“We are disappointed with today’s result, and to have to reschedule our launch of Starline”said John Vollmer, head of Boeing. ?Boeing and NASA will take the time necessary to ensure the safety and integrity of our spacecraft and the achievement of our mission objectives. “

The test mission was due to take place on Friday but had to be postponed to Tuesday after a Russian science module unexpectedly activated its thrusters after docking with the ISS, changing its orientation.

Read also Russian science module Nauka docked with the ISS

No longer needing Russian rockets

After ending its own space shuttle program in 2011, NASA secured the services of Boeing and SpaceX so as to no longer need Russian rockets to reach the ISS. SpaceX has already transported no less than ten astronauts to the Space Station, including Frenchman Thomas Pesquet, aboard its Crew Dragon spacecraft.

Also read the interview: Thomas Pesquet ready for a new takeoff into space

For its part, Boeing has fallen behind. In December 2019, during a first test flight, a software problem had caused a problem in the way the capsule had ignited its thrusters.

As a result, Starliner had not had enough fuel to reach the ISS and turned back to Earth prematurely. Subsequently, an investigation showed that the capsule had almost experienced a serious flight anomaly on entering the atmosphere. NASA called the mission Ť high visibility close call ť, a rare name reserved for flights that have come close to disaster.

Read also After a failure in space, a successful return to Earth for the Starliner capsule

Steve Stich, head of NASA’s commercial flights program, told the press last week that he was confident this time around. “We want it to go well, we expect it to go well and we have prepared as best we can”, he said. ?Starliner is a great vehicle but we know how difficult it is, and it’s also a test flight so I’m sure we’ll learn something from it. “

The capsule is expected to carry more than 180 kg of equipment to the ISS and bring back more than 250, when it completes its mission in the West American desert.

The World with AFP

Read also Russian science module Nauka docked with the ISS

No longer needing Russian rockets

Also read the interview: Thomas Pesquet ready for a new takeoff into space

For its part, Boeing has fallen behind. In December 2019, during a first test flight, a software problem had caused a problem in the way the capsule had ignited its thrusters.

Read also After a failure in space, a successful return to Earth for the Starliner capsule

The capsule is expected to carry more than 180 kg of equipment to the ISS and bring back more than 250, when it completes its mission in the West American desert.

The World with AFP

Waking up in anxious early morning after being chased by a wild beast, missing an essential exam or faced a natural disaster … As painful as they are banal, nightmares can in some cases be a true pathology: it is the “nightmarish disease”, which corresponds to repeated episodes (more than one per week, for more than six months) with an impact on daily life.

However, there are effective treatments, although still little developed in France, reviewed by Alain Perrier and Pierre Geoffroy (psychiatry department of the Bichat-Claude-Bernard hospital, AP-HP, GHU Paris psychiatry and neurosciences) and their colleagues. , in an article that appeared online on July 15 in the journal Sleep medicine. The The authors focus in particular on mental imagery repetition therapy (RIM), also known as mental image re-scripting. Derived from behavioral and cognitive therapies, this approach, developed in the United States in the 1990s, is the only one to have obtained grade A (highest) recommendations from American learned societies. ADR reduces the amount of bad dreams and associated distress by about 70%, according to randomized studies.

Its principle: to teach the patient to rewrite the scenario of his nightmare by creating positive images. Pierre Geoffroy, psychiatrist and senior author of the article, remembers the spectacular results in one of his first patients treated by RIM: a woman in her forties, mother of three children. Ten years earlier, this engineer had seen her colleague die before her eyes in an explosion on a construction site.

?She developed post-traumatic stress disorder, with a lot of nightmares where she relived that scene. To sleep better, she started drinking alcohol, then she lost control, says Pierre Geoffroy. Hospitalized in our department for withdrawal, we offered her a mental imagery repetition therapy, since the nightmares were very pervasive. She imagined an explosion scene? of confetti. ” In a few days, his frightening dreams disappeared, his craving (urge) for alcohol regressed and his other symptoms of post-traumatic stress were put at bay, underlines the psychiatrist, who now offers RIM in individual sessions or group.

A simple and effective technique

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A simple and effective technique

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Let the author of these lines be allowed to resuscitate a childhood memory, an echo of a summer camp where, after having made a group of kids trudge on the Aubrac, an instructor scratching his guitar engraved them this in memory around a campfire, chords of do and of sol major in support: “It was in prehistoric times / Here are two or three hundred thousand years, / A bizarre being was born / Close relative of the orangutan. / Standing on his hind legs, / Dressed in buffalo skin briefs, / He was going to conquer the Earth, / He was the man from Cro-Magnon./ The man from Cro? / The man from my? / The man from gnon / The Cro-Magnon man (poum!) / Cro de Magnon man / This is not can / Cro-Magnon man (pan pan) / Cro de Magnon man / This is not pas du can / The Cro-Magnon man. “

There is sometimes very little, the thickness of a hair, between the light and the serious, between the facetious and the poignant. It is with this song from the 1950s in mind, signed by Les Quatre Barbus, that we witness, at the Musée de l’homme, the opening of “the” black box in a silence almost as religious as that which presides over the presentation of a relic. First comes out the skull of “Cro-Magnon 1” then his mandible – his lower jaw. If Pontius Pilate were to witness the scene, he would say: “Ecce Homo sapiens” understand ” here is the man “.

The meeting with the first prehistoric representative of our species dates from 1868. Now is the time for the craze for this distant past of the Earth. As explained by paleoanthropologist Antoine Balzeau (Muséum national d’histoire naturelle [MNHN] and CNRS): ?In Western Europe, we still imagine that God put his finger and created man in his image. The question is more of when mankind dates back: does its birth conform to the biblical calendar or have there been humans long before? With the fossils of extinct animal species, some believe the time is probably longer than previously thought. ” There was a first “alert” in 1856 with the discovery of bones and the top of a curious skull on the German Neanderthal site but, specifies Antoine Balzeau, ?It was not accepted as a fossil piece at all. At the time, we did not have any of the precise dating methods today. These are the beginnings of paleontology, of going back in time ?.

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This handout photograph taken and released by the Russian Space Agency Roscosmos on July 29, 2021, shows the Russian Multipurpose Laboratory Module “Nauka” (Science) docking to the International Space Station (ISS). – RESTRICTED TO EDITORIAL USE – MANDATORY CREDIT “AFP PHOTO / Russian space agency Roscosmos / handout ” – NO MARKETING – NO ADVERTISING CAMPAIGNS – DISTRIBUTED AS A SERVICE TO CLIENTS
(Photo by Oleg NOVITSKY / RUSSIAN SPACE AGENCY ROSCOSMOS / AFP) / RESTRICTED TO EDITORIAL USE – MANDATORY CREDIT “AFP PHOTO / Russian space agency Roscosmos / handout ” – NO MARKETING – NO ADVERTISING CAMPAIGNS – DISTRIBUTED AS A SERVICE TO CLIENTS

After an eight-day trip to space and almost fifteen years behind the initial plans, the new Russian scientific module Nauka docked, Thursday, July 29, at the International Space Station (ISS), not without having encountered a temporary propellant problem.

A few hours after docking, the cosmonauts thus reported the unexpected ignition of Nauka’s engines, forcing them to turn on those of the Russian segment of the ISS to compensate for the movement produced on the orbital laboratory.

“The thrusters started to work (?) unexpectedly and inadvertently moving the station 45 degrees out of position. The recovery operations put it back in its position [initiale] and the crew is not in danger ?NASA explained on Twitter. ?The ignition of the thrusters has ceased and the loss of position has been stopped. The station is back to the expected position ť, commented NASA in its live broadcast of the flight control.

Contact and capture, docking confirmed. At 9:29am ET, the @Roscosmos Nauka science module arrived at the Earth-faci? https://t.co/pRnMzzKW33

– NASA (@NASA)

At a press conference, NASA human spaceflight manager Kathy Lueders called the incident “Really exciting time”, while thanking the crew for rectifying the situation.

Boeing Starliner test launch postponed

The American space agency also revealed that the space freighter Dragon of the SpaceX program launched by the American billionaire Elon Musk, currently attached to the international station, had been put on stand-by and ready to evacuate the crew if necessary. As a result of this incident, the test launch of the unmanned Boeing Starliner spacecraft to the international station has been postponed until at least August 3 for the duration of an ongoing investigation.

Read also SpaceX’s Crew Dragon capsule docked with the International Space Station

Science (Ť science ť in russian, to pronounce ŤNaoukať in French) took off on July 21 aboard a Proton-M rocket from the Russian Baikonur Cosmodrome in Kazakhstan. At the end of these eight days in space, necessary to position itself in the same orbit as the ISS, this space laboratory docked at 4:29 p.m. (3:29 p.m. in Paris) at the Russian service module Zvezda .

The docking was to take place in automatic mode, but cosmonaut Oleg Novitsky, currently on board the ISS, took manual control of the module to guide him over the very last meters. “New module, new perspectives for Russian cosmonautics”, meanwhile greeted on Twitter cosmonaut Ivan Vagner.

Several months and a series of extra-vehicular outings will still be necessary to make Nauka fully operational and integrated into the ISS. This is the first time in eleven years that a new Russian module has joined the orbital laboratory.

International cooperation works

The operation was closely scrutinized by the European Space Agency (ESA), Nauka taking with him one of his equipment, the ERA robotic arm, which will be installed outside the module.

After a successful launch and launching into orbit, Nauka’s route had been marked by several technical issues, forcing Roscosmos to maneuver and for a while raising fears that the module could not reach the ISS. “We were concerned for the first three days, there was a loss of telemetry”, said the head of the Russian space agency Dmitry Rogozin, adding that a “State commission will analyze all observations”.

“Congratulations to all who are involved”, commented on Twitter ESA Director General Josef Aschbacher, NASA and private actor Boeing Space also congratulating the Russian space agency. The ISS and space exploration remain a rare area in which international cooperation functions, in a period of tensions between Russia and Western countries.

With a total weight of 20 tonnes for an interior volume of 70 m³ – making it one of the largest on the ISS – the module began to be assembled during the 1990s but its launch, initially scheduled for 2007, has been constantly delayed. Like other Russian space projects, it fell victim to funding issues, bureaucratic errors, and technical issues during its design.

This space laboratory replaces the Pirs module, much smaller, which detached from the ISS on Monday before burning up on re-entering the Earth’s atmosphere over the Pacific Ocean.

If Nauka is primarily a laboratory module, it will also provide “Additional volumes for workstations and cargo storage, places for water and oxygen regeneration equipment”, according to Roscosmos.

ESA’s robotic arm, meanwhile, had been almost ready since 2007 and was just waiting for this docking. Hanging on to Nauka and able to stand ” move “ along the Russian segment of the ISS, it can carry up to eight tonnes of equipment and will help astronauts in particular during their extra-vehicular outings.

Read also Space tourism on the launch pad

The World with AFP

Contact and capture, docking confirmed. At 9:29am ET, the @Roscosmos Nauka science module arrived at the Earth-faci? https://t.co/pRnMzzKW33

– NASA (@NASA)

At a press conference, NASA human spaceflight manager Kathy Lueders called the incident “Really exciting time”, while thanking the crew for rectifying the situation.

Boeing Starliner test launch postponed

Read also SpaceX’s Crew Dragon capsule docked with the International Space Station

International cooperation works

The operation was closely scrutinized by the European Space Agency (ESA), Nauka taking with him one of his equipment, the ERA robotic arm, which will be installed outside the module.

This space laboratory replaces the Pirs module, much smaller, which detached from the ISS on Monday before burning up on re-entering the Earth’s atmosphere over the Pacific Ocean.

Read also Space tourism on the launch pad

The World with AFP

Physicist, the first woman professor at the Ecole Polytechnique in 1992, and recognized for her tireless commitment to women and girls in the sciences, Claudine Hermann died on July 17, in Villejuif (Val-de-Marne), at the age 75.

A former student (class of 1965) of the Ecole normale supérieure de jeunes filles (ENSJF), she obtained an agrégée in physics in 1969. A specialist in solid-state physics, she defended a thesis of 3^e cycle in 1968 and a State thesis in 1976. She was successively a preparatory associate at the ENSJF, lecturer, professor at the Ecole Polytechnique, then professor emeritus from 2005. She was also vice-president of the department of physics of the Ecole Polytechnique from 1985 to 1992.

Her teachings, much appreciated by her students and colleagues who had the privilege of collaborating with her, focus in particular on statistical physics, semiconductor physics, and more generally condensed matter. Her research work at the Condensed Matter Physics Laboratory – she was Deputy Director from 1980 to 1992 – focused on optical pumping in semiconductors and the photoemission of polarized electrons.

Member of Demain la parité

In the 1990s, Claudine Hermann was determined to promote women and girls in science. She participates in the Demain la parité network (created in 1994) and is the co-author of reports on the place of girls, in preparatory science classes on the one hand (1997), and in major scientific schools on the other (1998). With the teacher-researchers Noria Boukhobza, anthropologist, and Huguette Delavault, mathematician (1924-2003), she published a report, “Teacher-researchers at the university: the place of women”, on which their book will be based. Teacher-Researchers at the University: Parity Tomorrow? (with the collaboration of Corinne Konrad, L’Harmattan, 2002).

From 1996 to 2006, she participated in the work of the ?Women and Science? group of the European Technology Assessment Network (ETAN) of the European Community, which in 2001 published the report ?Integrating the gender dimension, a factor of excellence ?.

In 2000, she co-founded the Femmes & Sciences association, of which she was the first president, then honorary president from 2004. In 2005, she participated in the founding of the European Platform of Women Scientists (EPWS ): around fifty European associations are members, ie 15,000 European women scientists. Vice-president from 2009 to 2017, she will be president from 2017 to 2021, and honorary president in 2021.

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Member of Demain la parité

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Hemp? Marijuana? Cannabis? These names refer to the same plant species, Cannabis sativa. During its domestication, this plant split into two main groups. There are, first of all, the varieties intended for the production of fibers (textiles and ropes) and seeds: this is the hemp group. Then there are the varieties which produce high concentrations of chemical compounds, the ?cannabinoids?, with famous psychoactive properties (of illegal use in most countries): this is the group of marijuana. As for the term cannabis, in common parlance, it designates the plant or the drug derived from it. None of these names, however, fit a scientific classification.

Ť The evolutionary history of cannabis has been studied very little ť, notes Luca Fumagalli, from the Faculty of Biology and Medicine of Lausanne (Switzerland). This gap has now been filled. The saga of Cannabis sativa, traced by an international team coordinated by this researcher, is told in the journal Science Advances July 16. Where we (re) discover that this fascinating plant is, in fact, one of the oldest domesticated plant species – and not only, far from it, for its soaring effects.

The authors analyzed the genomes of 110 varieties of hemp or marijuana: plants collected from the wild in Asia, local varieties, historic cultivars, modern hybrids. ” We took several years to collect these samples with a global geographic coverage ť, says Luca Fumagalli. The bans on marijuana, it is true, have not made things easier.

From the beginning of the Neolithic

The researchers deciphered the complete genomes of 82 varieties, and analyzed previously published genomic data for 28 other varieties. Then they compared them by bioinformatics. They also modeled different evolutionary scenarios. Verdict: this plant has been cultivated since the beginning of the Neolithic, 12,000 years ago. This domestication took place in East Asia, not in Central Asia as the researchers believed. Cannabis sativa, So, has likely been cultivated as a versatile source of fiber, seeds and insecticides and for its recreational properties.

Another surprise: none of the plants collected in nature, even in the Himalayas, were strictly speaking wild. All are “feral” plants, that is to say, formerly domesticated and then returned to nature. ” There is probably no wild cannabis anymore ť, sums up Luca Fumagalli. The study also reveals that this species diverged not in two, but in three lineages. The first brings together many feral varieties in China. As for the other two, they bring together the varieties which gave respectively hemp and marijuana, and which separated from each other about 4,000 years ago. Man, then, began to heavily select the plant for its ability to produce either fiber or cannabinoids. There has been very little genetic exchange between these two lines.

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From the beginning of the Neolithic

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” Right here, warns Matthieu Gounelle, professor at the National Museum of Natural History (MNHN) and head of the cosmochemistry team, tea towels and towels are not mixed. ” We may be in a sample preparation room of the mineralogy laboratory, not the slightest trace of a pebble from our good old Earth. The laminar flow hood, the various saws for cutting stones, the binocular microscope, the oven, scales, all this material is reserved for meteorites: ?We are trying to keep a tight border between the two universes, terrestrial rocks and extraterrestrials. We don’t want them to contaminate each other. “

The collection of rocks fallen from the sky is kept in the adjacent temperature-controlled room, where there is a ?dry cabinet? with a humidity level of no more than 3.5%. It is from there that, equipped with a glove, Matthieu Gounelle extracts this strange stone with a dark and patinated fusion crust, which keeps on its surface a number 37 affixed to the XIX^e century with indelible red paint. Here is the Chassigny meteorite, named after this village of Haute-Marne where it fell and was found in 1815.

He is a doctor – and therefore necessarily a man of science? – Doctor Pistollet, who, rushing to the scene from Langres where he works, goes down in history by narrating the events. A story that we find in the Annals of Chemistry and Physics, published in 1816: ?On October 3, around half past eight in the morning, the weather being slightly clear and calm, the east wind blowing very lightly, we heard in the commune of Chassigny and the surrounding villages, at a distance of three and four leagues, a noise which seemed to be due to numerous discharges of musketry, interspersed with heavy cannon fire. This noise (?) had already lasted for a few minutes when a man working in a vineyard (?), Hearing a hiss similar to that of a cannonball, saw an opaque body fall about 400 meters away from which thick smoke escaped. “

Three kilos vanished

The farmer discovers in a field a hole half a meter in diameter as well as pieces of a rock which seems curious to him. ?Having picked up one of these fragments, he found it hot as if it had been exposed to a strong sun, continues Doctor Pistollet. He brought it back to the village, where soon, this fact having spread, other inhabitants went to collect these stones. Arrived in this village two days later, and having been shown one of these stones to me, I soon recognized an aerolite. “

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Three kilos vanished

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Seagulls or crows feeding on landfills or in disemboweled trash bags, nothing seems more commonplace to us. But difficult to resist these images. Filmed on a mobile phone by Richard Major, from the Museum of Australia, in Sydney, they show a Sulfur-crested cockatoo grabbing the lid of a dumpster with its beak, pulling it up then tilting, in order to clear access to the possible feast. The strength, but above all the skill and cleverness of the bird appear striking. “When I saw them, I knew that we had to study this innovation”, says Lucy Aplin, behavioral biologist in the cognitive ecology laboratory of the Max Planck Institute in Radolfzell (Germany). At the end of four years of participatory research, combining scientists and amateurs, the team has just announced its results in the journal Science of July 23, which can easily be summed up: this behavior is acquired through social learning. In other words, parrots have made a cultural adaptation to better understand the urban environment.

A great figure in ornithology, Lucy Aplin is known for her work on animal cultures. She revisited a mythical example, a century old: the learning of the opening, by blue tits, of the metal caps of milk bottles left on the doorstep in Great Britain. She continued her work with numerous experiments in semi-freedom on passerines. ?The difference lies in the complexity and the steps required to open these skips, indicates the ornithologist. I suspected that it must also be social learning. But it had to be shown. “

Between males

To do this, the team took advantage of the observations of 1,322 people across the municipalities of Sydney and Wollongong. They made it possible to follow the gradual extension of the practice, like a wave, going from 3 quarters before 2018 to 44 at the end of 2019. The recordings often show one of the birds performing the delicate maneuver, under the gaze of several of its congeners. Which of them in turn become experts? A minority, around 10%, according to more precise studies carried out on certain sites. The marking and then monitoring of 500 individuals at three sites did not reveal any particular transmission between parents and children. On the other hand, the know-how touches the different generations of birds, by following the networks of sociability.

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Between males

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Seismic waves provide information on the properties and limits of the interior of a planet. The shear waves that come from an earthquake and reflect off the iron-nickel core are detected by the Insight seismometer, and give us an estimate of the size of the core. The strength of the reflected waves shows that the nucleus is in a liquid state, in which the shear waves cannot propagate.

Slowly but surely, Mars reveals its intimacy. 943 ?soils? (or Martian days) after its spectacular landing on November 26, 2018 in the heart of the Elysium Planitia plain, NASA’s InSight mission, devoted to Martian seismology, announces a breakthrough in the knowledge of the sub- ground of the red planet.

In three articles published Thursday, July 22 in the journal Science, the team of the French seismometer SEIS (for Seismic Experiment for Interior Structures), manufactured with the help of Switzerland, explains how it used the seismic signals produced by a dozen Martian earthquakes to probe the inner layers of the star. Core, mantle, crust? Mars turns out to have an internal structure quite different from that of Earth.

The depths of a planet are a reflection of its origin and its evolution. Its inner layers can deliver information on its formation conditions in the early solar system as well as on its geomagnetic and geological activity, past and present. At least when we manage to characterize them with precision. What, for the moment, has been achieved only for the cases of the Earth and the Moon by studying, thanks to networks of seismometers, the way in which the seismic waves propagate and are reflected in the subsoil at the time earthquakes.

Real challenge

Hence the interest of the InSight mission. This consisted in placing on the ground of Mars a geophysical station equipped with a seismometer. Then to try to detect using this unique instrument – designed by the Institut de physique du globe de Paris (IPGP) under a CNES project management, in collaboration with several French, British, German and French laboratories and industrialists. Swiss – earthquakes in order to access better estimates of the internal composition of Mars. A real challenge because if, on this planet devoid of plate tectonics, earthquakes are relatively frequent, they are of low intensity. And in practice, only a handful of them are able to generate the right signals.

This is the feat that the SEIS team achieved by analyzing the seismic waves produced directly or indirectly by around ten of these events. The result ? He shows that while being close to that of Earth, the internal structure of Mars presents peculiarities that could be used to explain its disastrous evolution towards a dry, cold, devoid of atmosphere and geologically moribund world.

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Real challenge

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