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He didn’t get the job. But 500 years after his death, the design for what would have been the world’s longest bridge span of its time intrigued researchers at MIT, who wondered how thought-through Leonardo’s concept was and whether it really would have worked. Spoiler alert: Leonardo knew what he was doing. To study the question, recent graduate student Karly Bast MEng ’19, working with professor of architecture and of civil and environmental engineering John Ochsendorf and undergraduate Michelle Xie, tackled the problem by analyzing the available documents, the possible materials, and construction methods that were available at the time, and the geological conditions at the proposed site, which was a river estuary called the Golden Horn....

For many years, scientists have been aware of the unequal number of asteroids between the L4 and L5 swarms, but the cause of this asymmetry has remained elusive. Despite both swarms currently exhibiting nearly identical stability and survival properties in the Solar System, researchers believe that their differences originated during the earlier stages of the Solar System’s development. Uncovering the root of this disparity could provide new information about the Solar System’s formation and evolution....

In an unprecedented effort, hundreds of thousands of researchers and clinicians worldwide are locked in a race against time to develop cures, vaccines, and better diagnostic tests for COVID-19, the illness caused by the virus SARS-CoV-2. Over 1,650 articles on COVID-19 are already listed in databases such as Google Scholar, while dozens more are added daily. The register ClinicalTrials.gov lists over 460 ongoing clinical trials on COVID-19, although the majority are still in the earliest stages....

Scientists studying a ‘twin’ of the Milky Way have used the W. M. Keck Observatory and Subaru Observatory to accurately model how it is swallowing another, smaller galaxy. Their findings have opened the way to a better understanding of how structure forms in the universe and are being published in the Monthly Notices of the Royal Astronomical Society this week. The work, led by Caroline Foster of the Australian Astronomical Observatory, has used the Umbrella (NGC 4651) galaxy to reveal insights in galactic behavior....

On October 15, 2022, at a distance of 380,000 miles (620,000 km), NASA’s Lucy spacecraft captured this image (which has been cropped) of the Earth as a part of an instrument calibration sequence. The upper left of the image includes a view of Hadar, Ethiopia. This is home to the 3.2 million-year-old human ancestor fossil for which the spacecraft was named. Lucy is the first mission to explore the Jupiter Trojan asteroids....

In 2016, the computer program AlphaGo won four out of five games of Go against the world’s best human player. Given that a game of Go has more combinations of moves than there are estimated to be atoms in the universe, this required more than just sheer processing power. Rather, AlphaGo used artificial neural networks, which can recognize visual patterns and are even capable of learning. Unlike a human, the program was able to practice hundreds of thousands of games in a short time, eventually surpassing the best human player....

The correlation between the high concentration of fine particles and the severity of influenza waves is well known to epidemiologists. An interdisciplinary team from the University of Geneva (UNIGE) and the ETH Zürich spin-off Meteodat investigated possible interactions between acutely elevated levels of fine particulate matter and the virulence of the coronavirus disease. Their results, published in the journal Earth Systems and Environment, suggest that high concentrations of particles less than 2....

The planets in our Solar System formed in orbits that depended on the initial distribution of the matter in solar nebula. In particular, the most popular theory for the formation of giant gas planets argues that their rock-and-ice cores formed gradually through coagulation of smaller planetesimals until they were massive enough to accrete gaseous envelopes. The spatial distribution of gas in a primitive nebula is therefore critical not only to the accretion of the atmosphere of its giant planets but also to the formation of these early planetesimals....

Rings of dust have already been identified in many protoplanetary systems from their infrared and submillimeter emission. The origin of these rings is debated. They might have formed from dust “pile-up,” dust settling, gravitational instabilities, or even from variations in the optical properties of the dust. Alternatively, the rings could result dynamically from the orbital motions of planets that have already developed or that are well on their way. Planets will induce waves in the dusty discs which, as they dissipate, can produce gaps or rings....

A new NASA-led study using data from the Arctic Boreal Vulnerability Experiment (ABoVE) shows that carbon in Alaska’s North Slope tundra ecosystems spends about 13 percent less time locked in frozen soil than it did 40 years ago. In other words, the carbon cycle there is speeding up — and is now at a pace more characteristic of a North American boreal forest than of the icy Arctic. “Warming temperatures mean that essentially we have one ecosystem — the tundra — developing some of the characteristics of a different ecosystem — a boreal forest,” said study co-author Anthony Bloom of NASA’s Jet Propulsion Laboratory in Pasadena, California....

Scientists using the Herschel Space Observatory made new observations of asteroid Apophis as it approached Earth this past weekend. The data show the asteroid to be bigger than first estimated, and less reflective. Discovered in 2004, Apophis was initially thought to have a 2.7 percent chance of impacting Earth in 2029. Additional observations of the asteroid ruled out any possibility of an impact in 2029. However, Apophis is expected to make a record-setting — but harmless — close approach to Earth on April 13, 2029, when it comes no closer than 18,300 miles (29,450 kilometers) above Earth’s surface....

During the past two decades, astronomers have tried to pin down the distance by measuring the distances to stars either behind or within the nebula as determined by seeing absorption lines from the nebula in their spectra but the distances to those stars are in turn likewise uncertain, and parallax measurements of some of the stellar distances have also been unreliable. Efforts have also been made recently to measure the distance using the motions of the nebular gas directly, with published estimates suggesting a firm distance less than 2600 light-years and consistent with the old value of 2500 light-years....

The National Oceanic and Atmospheric Administration have been observing the Sun’s corona using the Large Angle and Spectrometric Coronagraph on the NASA and European Space Agency Solar and Heliospheric Observatory spacecraft since 1995 to track space weather that could impact Earth. However, the LASCO instrument has a blind spot that hinders observations of the middle solar corona, where the solar wind originates. New study reveals long, web-like structures in Sun’s middle corona....

The true identity of centaurs, the small celestial bodies orbiting the sun between Jupiter and Neptune, is one of the enduring mysteries of astrophysics. Are they asteroids or comets? A new study of observations from NASA’s Wide-field Infrared Survey Explorer (WISE) finds most centaurs are comets. Until now, astronomers were not certain whether centaurs are asteroids flung out from the inner solar system or comets traveling in toward the sun from afar....

Black holes can be petite, with masses only about 10 times that of our sun — or monstrous, boasting the equivalent in mass up to 10 billion suns. Do black holes also come in size medium? NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, is busy scrutinizing a class of black holes that may fall into the proposed medium-sized category. “Exactly how intermediate-sized black holes would form remains an open issue,” said Dominic Walton of the California Institute of Technology, Pasadena....

The scientists claim to have found evidence of the location of a neutron star that was left behind when a massive star ended its life in a gigantic explosion, leading to a famous supernova dubbed Supernova 1987A. For more than 30 years astronomers have been unable to locate the neutron star – the collapsed leftover core of the giant star – as it has been concealed by a thick cloud of cosmic dust....

The network is only partially complete, and will be finished in 2014. It should allow the forecast of upcoming storms and floods with much greater precision, and provide a model warning system for flooding. Atmospheric rivers flow at about 1.5 kilometers above the ocean surface, and extend thousands of miles out to sea, carrying as much water as 15 Mississippi Rivers. It strikes a coast as a series of storms, which arrive for days or weeks on end....

“It’s 200 million years older than the previously oldest known crater, which was the over 200-kilometer Vredefort Dome crater in South Africa,” said Timmons Erickson, a research scientist with the Astromaterials Research and Exploration Science division, or ARES, at NASA’s Johnson Space Center. Erickson made the discovery leading a team of researchers that included Christopher Kirkland, Nicholas Timms, and Aaron Cavosie from Curtin University in Australia and Thomas Davison from Imperial College London....

Dr. Tallie Z. Baram, corresponding author and distinguished professor in the Departments of Anatomy & Neurobiology, Pediatrics, Neurology, and Physiology & Biophysics at the University of California, Irvine, and Matthew T. Birnie, first author, a postdoctoral researcher at the University of California, Irvine, discuss the principles of emotional brain circuit formation learned from animal studies and their effects on children’s cognitive development and mental health in a study that was recently published in the journal Science....

Biologists at Tufts University School of Arts and Sciences have discovered a bioelectric signal that can identify cells that are likely to develop into tumors. The researchers also found that they could lower the incidence of cancerous cells by manipulating the electrical charge across cells’ membranes. “The news here is that we’ve established a bioelectric basis for the early detection of cancer,” says Brook Chernet, doctoral student and the first author of a newly published research paper co-authored with Michael Levin, Ph....