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What's Next for SpaceX's Starship?

✇Slashdot
EditorDavid
The Street interviewed Chad Anderson, founder/managing partner of the "space economy" investment firm Space Capital, who calls SpaceX's progress "unprecedented," and believes their next launch could carry "operational" payloads like Starlink satellites. Anderson added that Starship reaching orbital velocity and reentering the atmosphere at those speeds (roughly 16,000 miles per hour) was "a really big deal," though it's specifically important for the reusability of the vehicle, which would further cheapen the cost of launch. "The fact that they did all those things and they can now move into operations as an investor is hugely important and significant," Anderson said. "Having an operational Starship vehicle is really important because, at the moment, they just can't launch Starlink satellites fast enough. Starship is going to be able to launch 10 times more than Falcon 9 can, and that's really important...." The ship is so big that, according to Anderson, Starship could conceivably serve as a space station, or a hotel, or a manufacturing facility. There is also the potential of Starship actually competing with commercial airlines, flying, for example, from New York to Shanghai in 45 minutes. Clayton Swope, senior fellow at CSIS, also believes Starship could be used for "last-mile delivery... where you could move something in less than an hour, anywhere from a point on Earth to another point on Earth, and you're just kind of using space as that transit point." There's also defense applications. Defense One notes the U.S. Defense Department uses SpaceX to launch most of its satellites. "With a payload capacity of 100 to 150 tons, Starship could carry a bunch of satellites simultaneously and increase the Space Force's launch rate as it builds out a network of hundreds of satellites in low-Earth orbit." Once Starship is operational, it will be able to put things into higher orbits, which is key for the Pentagon's push to operate in the cislunar environment, the area between the geosynchronous orbit and the moon. "The Chinese have already begun cislunar operations and have put vehicles on the far side of the moon, which is something the U.S. doesn't really have the ability to do right now," said Bryan Clark, a senior fellow at the Hudson Institute. However, the advantage the U.S. will get with Starship "won't last forever," and it will take years to build satellites specifically designed to take advantage of the rocket's payload capacity, said Todd Harrison, a senior fellow at the American Enterprise Institute. "At this rate, they will have Starship operational this year. We need payloads to go on that, if we're actually going to take advantage of it during this window of opportunity when it's a capability only we have. If you want those payloads available next year, you needed to start building them five years ago," Harrison said. Starship could be used to put very large objects into space, such as fuel barges or energy stations, at a reasonable cost. "You could use this to put up an orbital bus that you can then put on and remove payloads from, so you can have a satellite on orbit that's basically a large docking station," Clark said... "[I]t could be a way to do that kind of thing where you establish essentially an unmanned, little space station that can carry various payloads."

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Physicist Claims Universe Has No Dark Matter and Is Twice As Old As We Thought

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BeauHD
schwit1 shares a report from ScienceAlert: Sound waves fossilized in the maps of galaxies across the Universe could be interpreted as signs of a Big Bang that took place 13 billion years earlier than current models suggest. Last year, theoretical physicist Rajendra Gupta from the University of Ottawa in Canada published a rather extraordinary proposal that the Universe's currently accepted age is a trick of the light, one that masks its truly ancient state while also ridding us of the need to explain hidden forces. Gupta's latest analysis suggests oscillations from the earliest moments in time preserved in large-scale cosmic structures support his claims. "The study's findings confirm that our previous work about the age of the Universe being 26.7 billion years has allowed us to discover that the Universe does not require dark matter to exist," says Gupta. "In standard cosmology, the accelerated expansion of the Universe is said to be caused by dark energy but is in fact due to the weakening forces of nature as it expands, not due to dark energy." [...] Current cosmological models make the reasonable assumption that certain forces governing the interactions of particles have remained constant throughout time. Gupta challenges a specific example of this 'coupling constant', asking how it might affect the spread of space over exhaustively long periods of time. It's hard enough for any novel hypothesis to survive the intense scrutiny of the scientific community. But Gupta's suggestion isn't even entirely new -- it's loosely based on an idea that was shown the door nearly a century ago. In the late 1920s, Swiss physicist Fritz Zwicky wondered if the reddened light of far distant objects was a result of lost energy, like a marathon runner exhausted by a long journey across the eons of space. His 'tired light' hypothesis was in competition with the now-accepted theory that light's red-shifted frequency is due to the cumulative expansion of space tugging at light waves like a stretched spring. The consequences of Gupta's version of the tired light hypothesis -- what is referred to as covarying coupling constants plus tired light, or CCC+TL -- would affect the Universe expansion, doing away with mysterious pushing forces of dark energy and blaming changing interactions between known particles for the increased stretching of space. To replace existing models with CCC+TL, Gupta would need to convince cosmologists his model does a better job of explaining what we see at large. His latest paper attempts to do that by using CCC+TL to explain fluctuations in the spread of visible matter across space caused by sound waves in a newborn Universe, and the glow of ancient dawn known as the cosmic microwave background. While his analysis concludes his hybrid tired light theory can play nicely with certain features of the Universe's residual echoes of light and sound, it does so only if we also ditch the idea that dark matter is also a thing. The research has been published in The Astrophysical Journal.

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Le fast-FPS et bullet hell Bears In Space est sorti

✇NoFrag
Estyaah

Comme prévu, Bears In Space est sorti le 22 mars dernier. Ce fast-FPS à la direction artistique loufoque et colorée propose un gameplay inspiré de Serious Sam, mixé avec du bullet hell, ce principe d’inonder l’écran de projectiles à éviter, tout en détruisant la myriade d’adversaires. Lors de la publication d’une démo il y a quelques mois, nous n’avions pas forcément été conquis. Cependant, la réalisation est très propre, et le jeu semble contenter les fans du genre. En plus, le trailer d’annonce est plutôt chouette, sous forme de parodie des publicités des années 90 pour les Action Man.

Si Bears In Space vous tente, vous pouvez déjà tester la démo, toujours disponible sur la page Steam du jeu. Et si vous êtes conquis, vous pouvez profiter de la promo de lancement de –10 % jusqu’au 29 mars sur Steam et l’Epic Games Store, ce qui le fait à 18 €.

Henrietta Leavitt, Cosmology Pioneer, Receives Belated Obituary

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BeauHD
Longtime Slashdot reader necro81 writes: The New York Times has an occasional series called "Overlooked," whereby notable people whose deaths were overlooked at the time receive the obituary they deserve. Their latest installment eulogizes Henrietta Swan Leavitt, who passed away in 1921 at age 53. From the report: "In the early 20th century, when Henrietta Leavitt began studying photographs of distant stars at the Harvard College Observatory, astronomers had no idea how big the universe was... Leavitt, working as a poorly paid member of a team of mostly women [computers] who cataloged data for the scientists at the observatory, found a way to peer out into the great unknown and measure it." Leavitt discovered the period-luminosity relationship for Cepheid variable stars. The relationship, now known as Leavitt's Law, is a crucial rung in the cosmic distance ladder, the methods for measuring the distance to stars, galaxies, and across the visible universe. From the report: "[Leavitt's Law] underpinned the research of other pioneering astronomers, including Edwin Hubble and Harlow Shapley, whose work in the years after World War I demolished long-held ideas about our solar system's place in the cosmos. Leavitt's Law has been used on the Hubble Telescope and the James Webb Space Telescope in making new calculations about the rate of expansion of the universe and the proximity of stars billions of light years from earth. 'She cracked into something that was not only impressive scientifically but shifted an entire paradigm of thinking...'"

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Scientists Complete Construction of the Biggest Digital Camera Ever

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BeauHD
Isaac Schultz reports via Gizmodo: Nine years and 3.2 billion pixels later, it is complete: the LSST Camera stands as the largest digital camera ever built for astronomy and will serve as the centerpiece of the Vera Rubin Observatory, poised to begin its exploration of the southern skies. The Rubin Observatory's key goal is the 10-year Legacy Survey of Space and Time (LSST), a sweeping, near-constant observation of space. This endeavor will yield 60 petabytes of data on the composition of the universe, the nature and distribution of dark matter, dark energy and the expansion of the universe, the formation of our galaxy, our intimate little solar system, and more. The camera will use its 5.1-foot-wide optical lens to take a 15-second exposure of the sky every 20 seconds, automatically changing filters to view light in every wavelength from near-ultraviolet to the near-infrared. Its constant monitoring of the skies will eventually amount to a timelapse of the heavens; it will highlight fleeting events for other scientists to train their telescopes on, and monitor changes in the southern sky. To do this, the team needed a Rolls Royce of a digital camera. Mind you, the camera actually cost many million times that of an actual Royce Royce, and at 6,200 pounds (2,812 kilograms), it weighs a lot more than a fancy car. Each of the 21 rafts that makes up the camera's focal plane is the price of a Maserati, and are worth every penny if they collect the sort of data scientists expect them to. "I'm personally most excited to study the expansion of the Universe using gravitational lenses to better understand Dark Energy," said Aaron Roodman, a physicist at SLAC and lead on the camera program, in an email to Gizmodo. "That means two things: 1) measuring the brightness in all six of our filters of literally billions of galaxies and very carefully measuring their shape, which has been subtly altered by the bending of light by matter, and 2) discovering and studying very special objects where a distant quasar is almost perfectly lined up with a more nearby galaxy." Speaking through a SLAC release, Rodman said the camera's images could "resolve a golf ball from around 15 miles away, while covering a swath of the sky seven times wider than the full moon." The first images from the Rubin Observatory are slated to be publicly released in March 2025, which feels like a long way away. But several important agenda items still need to happen. For one, the SLAC team has to ship the LSST camera safely to Chile from its current lodgings in northern California. (Don't worry -- they've made a test run of the journey.) Then, the observatory's mirrors need to be readied for testing and the observatory's dome has to be completed, among some other tasks. But whenever all that is complete, the legacy survey will launch into a decade's worth of scientific discovery. Rubin Observatory estimates suggest that LSST could "increase the number of known objects by a factor of 10," according to a SLAC release.

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