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A New Nuclear Rocket Concept Could Slash Mars Travel Time in Half

"Engineers from Ohio State University are developing a new way to power rocket engines," reports Gizmodo, "using liquid uranium for a faster, more efficient form of nuclear propulsion that could deliver round trips to Mars within a single year..." Nuclear propulsion uses a nuclear reactor to heat a liquid propellant to extremely high temperatures, turning it into a gas that's expelled through a nozzle and used to generate thrust. The newly developed engine concept, called the centrifugal nuclear thermal rocket (CNTR), uses liquid uranium to heat rocket propellant directly. In doing so, the engine promises more efficiency than traditional chemical rockets, as well as other nuclear propulsion engines, according to new research published in Acta Astronautica... Traditional chemical engines produce about 450 seconds of thrust from a given amount of propellant, a measure known as specific impulse. Nuclear propulsion engines can reach around 900 seconds, with the CNTR possibly pushing that number even higher. "You could have a safe one-way trip to Mars in six months, for example, as opposed to doing the same mission in a year," Spencer Christian, a PhD student at Ohio State and leader of CNTR's prototype construction, said in a statement. CNTR promises faster routes, but it could also use different types of propellant, like ammonia, methane, hydrazine, or propane, that can be found in asteroids or other objects in space. "Some potential hurdles include ensuring that the methods used for startup, operation and shutdown avoid instabilities," according to the researchers' announcement, as well as "envisioning ways to minimize the loss of uranium fuel and accommodate potential engine failures." But "This team's CNTR concept is expected to reach design readiness within the next five years..."

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NASA Says Mars Rover Discovered Potential Biosignature Last Year

NASA: After a year's worth of scientific scrutiny, the 'Sapphire Canyon' rock sample remains the mission's best candidate for containing signs of ancient microbial life processes. A sample collected by NASA's Perseverance Mars rover from an ancient dry riverbed in Jezero Crater could preserve evidence of ancient microbial life. Taken from a rock named "Cheyava Falls" last year, the sample, called "Sapphire Canyon," contains potential biosignatures, according to a paper published Wednesday in the journal Nature. A potential biosignature is a substance or structure that might have a biological origin but requires more data or further study before a conclusion can be reached about the absence or presence of life. "This finding by Perseverance, launched under President Trump in his first term, is the closest we have ever come to discovering life on Mars. The identification of a potential biosignature on the Red Planet is a groundbreaking discovery, and one that will advance our understanding of Mars," said acting NASA Administrator Sean Duffy. "NASA's commitment to conducting Gold Standard Science will continue as we pursue our goal of putting American boots on Mars' rocky soil."

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Cette bactérie ultra-résistante est peut-être l’alliée insoupçonnée pour la survie dans l’espace

Chroococcidiopsis, de son petit nom, est une cyanobactérie extrêmement résistante. Dans un article pré-publié dans la revue Acta Astronautica, la chercheuse Daniela Billi de l'Université de Rome présente ses incroyables capacités et son intérêt toujours plus important en astrobiologie.

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