With Perseverance, NASA recovers in Mars
The March 2020 mission took off Thursday from Cape Canaveral in Florida, heading for the Red Planet. On board, the Perseverance rover will join its predecessor Curiosity to retrace the geological history of Mars and look for any traces of past life. It will land in February 2021 in the Jezero crater, the location of an ancient lake rich in clay, which may have retained the remains of organic compounds.
Artist’s impression of Perseverance contemplating the rock samples he will collect on Mars. Image Nasa
Accompanied by a miniature helicopter which will attempt to fly in the Martian atmosphere, Perseverance will also take rock samples that a future mission will have to repatriate to Earth. The rover will record the sounds of Mars (and its laser “pops”) with microphones and prepare for the arrival of humans on Mars by making oxygen and testing the radiation resistance of some space suit fabrics.
To read in detailed version With Perseverance, NASA recovers in Mars
The takeoff went well during all its first stages, until the rover left Earth for good, freed from its gravitational pull. Then he experienced a slight temperature problem. “Thursday around 11:30 am [17h30 à Paris, ndlr], we received a telemetry signal from Mars 2020 from NASA ground stations, reports the US space agency. The data indicates that the vessel has entered a state known as survival mode, mainly because the ship was a bit colder than expected when March 2020 passed into Earth’s shadow. ” But the problem was only temporary: “All temperatures are now nominal [conformes aux attentes, ndlr] and the ship came out of the shadow of the Earth. ” March 2020 returned to “travel” mode overnight from Thursday to Friday.
New delay for the James Webb telescope
We remain on the American side, and always in the family of great missions that require decades of preparation and billions of dollars. NASA has announced a new launch date for the future télescope spatial James Webb : October 31, 2021.
Software and electronics testing on the James Webb Space Telescope in February 2020. Photo Chris Gunn. Nasa
The development of JWST has a long history of delays, postponements and budget overruns. It was initially planned for it to take off in 2007 … Then the project was completely revised and NASA announced a departure in 2018. Today, the construction of the giant telescope is officially finished. It has been undergoing battery tests since the end of 2016, but one of them accidentally tore the heat shield. And then we found some loose screws. And valves damaged by the use of an inappropriate solvent. And poorly chosen cables have blown electrical circuits. In short, human errors, which cost months and hundreds of millions of dollars more. Lately, we were hoping for a launch in March 2021. But to top it off, the Covid pandemic has been there. Hopefully this will be the last twist …
In the meantime, the summer program for the JWST team is to validate the full test of the electrical systems (which has just been completed), then to do some acoustic and vibration tests.
3,200 satellites for Amazon
Bad news for our starry nights: the US Federal Communications Commission (FCC) has approved this friday Amazon’s Kuiper Project, which wants to place 3,236 satellites in low orbit to provide global access to the Internet. Half of the satellites will have to be launched before the end of July 2026, and the other half by the summer of 2029. The pace promises to be intense.
The night sky as seen from London in May 2020, with the movement of the stars (the small lines) and the track of the Starlink satellites (the long parallel lines). Photo Steve Elliott. CC BY SA
For its part, the competing project Starlink SpaceX already has 535 satellites in Earth orbit and expects to climb to at least 12,000. The craft are released in clusters of 60 at a time, at an average rate of one takeoff per month. The “train” of luminous points which cross the sky one after the other after take-off is impressive to observe with the naked eye … But once in their final orbit, the Starlink satellites continue to be visible by telescopes and worry strongly the astronomical community because they disrupt observations. Amazon has just announced that 10 billion dollars will be invested in the Kuiper project.
The volcanoes of Venus are still active
It gurgles in there! We knew that Venus was a planet with an infernal climate (92 times the atmospheric pressure of the earth and an average temperature of 462° C) and we can now say that it is still geologically active.
For a paper published in Nature Geoscience, the researchers studied the volcanic structures in the shape of circles found all over Venus and which are called crown. They are an undeniable mark of volcanism – molten rocks rise to the surface, pierce it and spill out in circles. But how long have they been frozen? Until now, it was thought that Venus has slowly cooled since the formation of the solar system, hardening its crust enough so that no molten rock from inside the planet could rise and pierce the surface. But we were wrong.
A Venusian corona, a circular volcanic formation, photographed by radar by the Magellan probe in 1991. Photo Nasa. JPL. Magellan
The researchers modeled as precisely as possible the upwelling of hot rocks (the “plumes”) From the mantle of Venus to its lithosphere, the outer layer of its earth’s crust. Their simulation, much more realistic than previous work on the subject, not only allows to identify “Several styles of interactions between plumes and the lithosphere, but also different stages of evolution”. In other words, computer models teach us what Venusian coronae look like according to their age.
3D simulation of two coronae on the surface of Venus (the black line is a lack of data). Image Laurent Montesi et al
Researchers now know the “Geological features present only in the still active coronæ” and it turns out from these clues that“At least 37 coronæ have been active very recently” on Venus, report the American geologist Laurent Montési. “This is the first time that we can point to specific structures and say, ‘Look, this is not an ancient volcano but one that is still active today. Dormant maybe, but not dead. “” Class.
Thomas Pesquet will be the first European to fly on a “Dragon”. The French astronaut has officially been assigned his second space mission, called Alpha. He will join the ISS in spring 2021 aboard SpaceX’s new spacecraft.