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First fully programmable quantum computer based on neutral atoms

New Scientist - Hace 7 horas 28 mins
Most quantum computers are based on superconductors or trapped ions, but an alternative approach using ordinary atoms may have advantages

A huge asteroid will fly safely by Earth today. Here's how to watch it live.

Live Science - Hace 7 horas 46 mins
You can watch a nearly mile-wide asteroid make its closest Earth approach for the next 200 years today. Here's how.

Celebrated malting barley came from a single plant

Science Daily - Hace 8 horas 49 mins
The 200-year-old malting barley variety 'Chevalier' was for a long time world-leading in beer brewing and is thought to have originated from a single plant. In a new study, researchers have investigated this claim. They have analyzed seed samples that are older than 150 years using molecular genetic methods. The results give a revealing insight into the plant breeding of times gone by.

World's deepest-dwelling squid spotted 20,000 feet under the sea

Live Science - Hace 9 horas 27 mins
Scientists spotted the world's deepest-dwelling squid 20,000 feet below the Philippine Sea while hunting for a lost WWII battleship.

Climate scientist and Netflix 'Don't Look Up' director talk comet metaphors and global warming (exclusive)

Live Science - Hace 10 horas 4 mins
Adam McKay, creator of Netflix's popular satire-comedy movie "Don't Look Up," and climate scientist Kate Marvel talk why the world needs more films like the comet metaphor movie.

Scorching alien planet takes seasons to an extreme

Live Science - Hace 10 horas 4 mins
Scientists have gotten a close look at an extreme case of seasons, thanks to a retired NASA telescope.

Covid-19 news: Joint flu and covid-19 vaccine could be offered in 2023

New Scientist - Hace 10 horas 7 mins
The latest coronavirus news updated every day including coronavirus cases, the latest news, features and interviews from New Scientist and essential information about the covid-19 pandemic

AI learns to create images from text descriptions by destroying data

New Scientist - Hace 10 horas 42 mins
A fresh approach to generating images based on text descriptions with AI, called a diffusion model, effectively un-destroys new images into existence

Which animals have the longest arms?

Live Science - Hace 10 horas 43 mins
Of all the living animals in the world, these are the ones with the longest arms, relative to body size.

11 of the world’s biggest man-made disasters

Live Science - Hace 10 horas 54 mins
We explore some of the biggest, most significant, and most harmful man-made disasters in human history, from nuclear explosions to oil spills

Diamonds: Formation, grading and other facts

Live Science - Hace 11 horas 18 mins
Diamonds are unique among gemstones, with intriguing physical properties and practical applications far beyond jewelry.

What is the difference between prokaryotic and eukaryotic cells?

Live Science - Hace 12 horas 15 mins
Learn about the many differences between prokaryotic and eukaryotic cells and how they evolved.

Astronomers Find Growing Number of Starlink Satellite Tracks

Slashdot - Science - Hace 12 horas 43 mins
A team of astronomers has used archival images from a survey telescope to look for Starlink tracks over the past two years. Over that time, the number of images affected rose by a factor of 35, and the researchers estimate that by the time the planned Starlink constellation is complete, pretty much every image from their hardware will have at least one track in it. Ars Technica reports: SpaceX's Starlink Internet service will require a dense constellation of satellites to provide consistent, low-latency connectivity. The system already has over 1,500 satellites in orbit and has received approval to operate 12,000 of them. And that has astronomers worried. Although SpaceX has taken steps to reduce the impact of its hardware, there's no way to completely eliminate the tracks the satellites leave across ground-based observations. [...] In response to complaints from the astronomy community, SpaceX put visors on later generations of Starlink satellites. The research team was able to compare the visibility of these different generations and found that the visors worked -- satellites with visors dropped in brightness by a factor of roughly 4.6 (the precise number depended upon the wavelength). The visibility, however, was still higher than the target set at a workshop that was meant to address this issue. Because these tracks are small and software already identifies and handles them, they don't have much of an effect on observations. The researchers estimate that, at present, there's only a 0.04 percent chance that a rare event will be missed because it coincides with a track. But because the problem is most acute in twilight observations, it's more likely to impact searches for objects within the Solar System. This would include comets and asteroids -- including asteroids that originated around other stars. But again, the problem is likely to get worse. SpaceX already has approval to increase the number of Starlink satellites to well over 10,000; the authors estimate that at 10,000, every image at twilight will likely contain a Starlink track. SpaceX has indicated it would eventually like to boost the numbers to over 40,000 satellites, at which point all twilight images are likely to have four tracks. And SpaceX isn't the only company planning on this sort of satellite service. If all the companies involved follow through on their plans, low Earth orbit could see as many as 100,000 of these satellites. Overall, the picture is mixed. The ZTF's main mission -- to pick out rare events caused by distant, energetic phenomena -- is largely unaffected by the growing number of satellite tracks. And because the percentage of events is currently small, tripling the number of satellites won't have a dramatic impact on observations. But a secondary science mission is already seeing a lot of light contamination, and matters are only going to get worse. The findings have been published in the journal Astrophysical Journal Letters.

Read more of this story at Slashdot.

NASA's Curiosity Rover Measures Intriguing Carbon Signature On Mars

Slashdot - Science - Hace 15 horas 43 mins
After analyzing powdered rock samples collected from the surface of Mars by NASA's Curiosity rover, scientists today announced that several of the samples are rich in a type of carbon that on Earth is associated with biological processes. From a report: While the finding is intriguing, it doesn't necessarily point to ancient life on Mars, as scientists have not yet found conclusive supporting evidence of ancient or current biology there, such as sedimentary rock formations produced by ancient bacteria, or a diversity of complex organic molecules formed by life. In a report of their findings to be published in the Proceedings of the National Academy of Sciences journal on January 18, Curiosity scientists offer several explanations for the unusual carbon signals they detected. Their hypotheses are drawn partly from carbon signatures on Earth, but scientists warn the two planets are so different they can't make definitive conclusions based on Earth examples. The biological explanation Curiosity scientists present in their paper is inspired by Earth life. It involves ancient bacteria in the surface that would have produced a unique carbon signature as they released methane into the atmosphere where ultraviolet light would have converted that gas into larger, more complex molecules. These new molecules would have rained down to the surface and now could be preserved with their distinct carbon signature in Martian rocks. Two other hypotheses offer nonbiological explanations. One suggests the carbon signature could have resulted from the interaction of ultraviolet light with carbon dioxide gas in the Martian atmosphere, producing new carbon-containing molecules that would have settled to the surface. And the other speculates that the carbon could have been left behind from a rare event hundreds of millions of years ago when the solar system passed through a giant molecular cloud rich in the type of carbon detected.

Read more of this story at Slashdot.

Proof of Concept Verifies Physics That Could Enable Quantum Batteries

Slashdot - Science - Lun, 17/01/2022 - 21:30
An anonymous reader quotes a report from New Atlas: For the first time, a team of scientists has now demonstrated the quantum mechanical principle of superabsorption that underpins quantum batteries in a proof-of-concept device. "Superabsorption is a quantum collective effect where transitions between the states of the molecules interfere constructively," James Quach, corresponding author of the study, told New Atlas. "Constructive interference occurs in all kinds of waves (light, sound, waves on water), and occurs when different waves add up to give a larger effect than either wave on its own. Crucially this allows the combined molecules to absorb light more efficiently than if each molecule were acting individually." In a quantum battery, this phenomenon would have a very clear benefit. The more energy-storing molecules you have, the more efficiently they'll be able to absorb that energy -- in other words, the bigger you make the battery, the faster it will charge. At least, that's how it should work in theory. Superabsorption had yet to be demonstrated on a scale large enough to build quantum batteries, but the new study has now managed just that. To build their test device, the researchers placed an active layer of light-absorbing molecules -- a dye known as Lumogen-F Orange -- in a microcavity between two mirrors. "The mirrors in this microcavity were made using a standard method to make high quality mirrors," explained Quach. "This is to use alternating layers of dielectric materials -- silicon dioxide and niobium pentoxide -- to create what is known as a 'distributed Bragg reflector.' This produces mirrors which reflect much more of the light than a typical metal/glass mirror. This is important as we want light to stay inside the cavity as long as possible." The team then used ultrafast transient-absorption spectroscopy to measure how the dye molecules were storing the energy and how fast the whole device was charging. And sure enough, as the size of the microcavity and the number of molecules increased, the charging time decreased, demonstrating superabsorption at work. "The idea here is a proof-of-principle that enhanced absorption of light is possible in such a device," Quach told New Atlas. "The key challenge though is to bridge the gap between the proof-of-principle here for a small device, and exploiting the same ideas in larger usable devices. The next steps are to explore how this can be combined with other ways of storing and transferring energy, to provide a device that could be practically useful." The research was published in the journal Science Advances.

Read more of this story at Slashdot.

China Claims First Omicron Case Arrived Through Foreign Mail

Slashdot - Science - Lun, 17/01/2022 - 18:02
An anonymous reader quotes a report from Insider: Officials in Beijing are telling people to avoid international mail and to open their packages outdoors and with gloves, saying cases of the Omicron coronavirus variant could have spread through foreign mail. Experts have repeatedly said that there is little risk of getting the coronavirus from mail. There is no indication that this has changed with the Omicron variant, though it is more infectious. But Robin Brant, the BBC's China correspondent, tweeted on Monday that Beijing was telling residents not to order goods from abroad, and to open packages outside with gloves and a mask on. The South China Morning Post also reported on Monday that Beijing's center for disease control and prevention said that people should order as little as possible from abroad, and that people should wear gloves and masks when opening any mail from high-risk countries. It comes as the center said the first recorded case of the Omicron variant in Beijing could have entered via mail. Officials in Beijing say the man who was infected was sent mail from Canada on January 7. They claim to have detected the Omicron variant on the letter. Canada's post office notes that the risk of the coronavirus spreading via mail is low as it doesn't live long on surfaces.

Read more of this story at Slashdot.

Fourth Pfizer Dose Is Insufficient to Ward Off Omicron, Israeli Trial Suggests

Slashdot - Science - Lun, 17/01/2022 - 16:40
A fourth dose of the Pfizer-BioNTech vaccine was insufficient to prevent infection with the omicron variant of Covid-19, according to preliminary data from a trial in Israel released Monday. Bloomberg reports: Two weeks after the start of the trial of 154 medical personnel at the Sheba Medical Center in Tel Aviv, researchers found the vaccine successfully raised antibody levels. But that only offered a partial defense against omicron, according to Gili Regev-Yochay, the trial's lead researcher. Vaccines which were more effective against previous variants offer less protection with omicron, she said. Still, those infected in the trial had only slight symptoms or none at all. Israel started rolling out the fourth dose of the vaccine to the over-60s and immunocompromised in late December amid a surge in cases. Since then, more than half a million Israelis have received the extra dose, according to the Health Ministry. The decision to give the fourth vaccine to the most vulnerable was the correct one, Regev-Yochay said at a virtual press conference, since it may have given additional benefit against omicron. But she added the results didn't support a wider rollout to the whole population.

Read more of this story at Slashdot.

Omicron Surge Shows Signs of Easing in States Hit Early by the Fast-spreading Variant

Slashdot - Science - Lun, 17/01/2022 - 14:03
Following weeks of soaring infections, the latest Covid surge is showing signs of slowing in a handful of areas hit earliest by the omicron variant -- offering a glimmer of hope that this wave is starting to ease. From a report: The U.S. has reported an average of nearly 800,000 cases per day over the past week, according to data compiled by Johns Hopkins University, more than three times the level seen during last winter's previous record. But in a handful of states and cities, particularly on the East Coast, cases appear to have plateaued or fallen in recent days. In New York, the seven-day average of daily new cases has been declining since hitting a record high of 85,000 per day on Jan. 9, according to Hopkins data. Cases there doubled during a number of seven-day periods in late December and early January, but are down sharply from last week to an average of 51,500. In New York City, average daily cases have fallen by 31% over the past week, state health department data shows. "There will come a time when we can say it's all over," Gov. Kathy Hochul said at a press conference Friday. "We're not there yet, but boy, it's on the horizon and we've waited a long time for that." New York is still reporting a high level of daily infections, ranking 15th out of all states, according to a CNBC analysis of population-adjusted case counts, down from the second-most just a few days ago. New Jersey also recently fell out of the top five, now ranking 20th, as the state has seen a 32% drop in average daily cases over the past week.

Read more of this story at Slashdot.

Ancient Mars may have had a liquid ocean despite freezing temperatures

New Scientist - Lun, 17/01/2022 - 14:00
A model based on Earth’s oceans and atmosphere explains how Mars could have been cold and wet 3 billion years ago

Unknown voices spark more brain activity in sleep than familiar ones

New Scientist - Lun, 17/01/2022 - 12:00
Unfamiliar voices seem to put the sleeping brain on alert in a way that familiar voices don’t

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