With the help of sound waves and a small plastic ball, researchers in the U.K. have designed a machine that generates truly 3D holographs.
The whole system is slightly smaller than a shoebox and makes simple images, like a butterfly or smiley face, that are less than an inch tall. Described in Nature, the device is one of the first 3D-image generators that also responds to touch and produces sound, says study coauthor Ryuji Hirayama, a materials science researcher at the University of Sussex.Read More
Ancient Egyptian catacombs stretch for kilometers underground. Branching off of the tunnels are rooms, and those rooms are stacked to the ceilings with jars holding more than 1 million mummified African sacred ibises.
Egyptians buried millions of these leggy, long-beaked birds as prayer offerings to Thoth, the god of wisdom and writing. Early archaeological work and snippets of ancient texts made most historians think these birds were raised in captivity somewhere near the catacombs. But a new analysis, published in the journal PLOSOne, of DNA from the mummified birds shows that the ibises were likely caught in the wild.Read More
NASA announced last week that it will contribute to a European Space Agency mission scheduled to launch in 2028. The spacecraft, called ARIEL (for Atmospheric Remote-sensing Infrared Exoplanet Large-survey), will be the first space mission dedicated to studying exoplanet atmospheres.
During its primary mission lasting some four years, ARIEL will study the atmospheres of roughly 1,000 exoplanets. NASA’s contribution, an instrument called CASE, will let astronomers tell whether these exoplanets’ skies are cloudy, hazy or clear. The results will help astronomers understand how planets and their atmospheres form and change over time.
So far, astronomers have discovered thousands of exoplanets that pass in front of their stars from our point of view. With the right tools, astronomers can study light from the host stars that pass through the planets’ atmospheres. This can reveal information like the chemical makeup and temperatures of these atmospheres as well as what chemical reactions are taking place there.
The James Webb Space Telescope, currently scheduled to launch in 2021, will be able to study exoplanet atmospheres. But since JWST will split its time between multiple projects, it will only focus on studying the atmospheres of a few exoplanets. ARIEL, however, will observe the skies of about 1,000 exoplanets, from rocky planets to Jupiter-like gas giants.
“I’m really looking forward to the ability to place individual planets within a statistical context,” said Mark Swain, an astrophysicist at NASA’s Jet Propulsion Laboratory who is heading production of the CASE instrument. “That is something which you need a large survey of exoplanets to do.”
CASE, which stands for Contribution to ARIEL Survey of Exoplanets, will capture wavelengths of visible and infrared light that carry evidence for clouds and hazes in planets’ skies. What makes something a cloud or haze? Clouds condense out of the atmosphere, like water droplets that make clouds in Earth’s sky. Hazes are molecules that often form through chemical processes when light interacts with molecules in the atmosphere.
Understanding whether an exoplanet has clouds or hazes will help astronomers better interpret other information about the planet’s atmosphere, like chemical makeup and temperature, and figure out what physical and chemical processes are happening.
Also, understanding chemical compositions of exoplanet atmospheres might help decide which of two leading theories for how planets form is most likely correct. One theory suggests that planets will tend to have similar fractions of heavy elements as their host stars, while another implies that the heavy element fractions could be quite different.
Finally, studying the atmospheres of 1,000 planets should help astronomers find out what’s typical and pick out interesting cases to delve into.
“When we see a single planet, a big question is, ‘Is this kind of like the others, or did something special happen here?’” Swain said. “And that’s a fundamental capability that ARIEL is going to give us.”
On November 11, SpaceX launched a Falcon 9 rocket carrying another 60 Starlink satellites, which will eventually provide internet service worldwide. The launch from Cape Canaveral Air Force Station made history by reusing a record number of rocket parts. But even with that feat in aerospace design, the launch wasn’t celebrated by everyone.Read More
If there was a wormhole in the center of our galaxy, how could we tell? Two physicists propose that carefully watching the motions of a star orbiting the Milky Way’s supermassive black hole might help scientists start to check. The researchers published the idea in a recent paper in the journal Physical Review D.
A wormhole is a hypothetical concept that connects two separate areas of space-time. Wormholes often appear in science fiction narratives like the 2014 film Interstellar as a convenient way to get from point A to point B in the vast universe. Physicists have many theories that describe how wormholes might behave, if they exist, but haven’t yet found any.Read More
Thousands of years ago, ancient Egyptians built their agricultural systems around the dependable movement of the Nile. Those rhythms date back much further than any human relative has been alive, scientists now find.
New research shows that the Nile has kept about the same course for its entire 30-million-year existence. This is likely thanks to a reliable flow of rocky material just below the Earth’s surface, which continually pushes up the Ethiopian Highlands, where the river starts, says an international team of researchers.Read More
Reluctant joggers, here’s some encouragement: Running even once a week has some benefits.
According to a new study, running 50 minutes a week, at a pace between a 10- and 7.5-minute mile, helped reduce the risk of death from cancer, cardiovascular disease and other causes. Working out more than that didn’t convey significantly more health benefits, say the researchers, based on a review of over a dozen studies.Read More
Over the past couple of decades, astronomers have discovered thousands of alien planets and solar systems. These worlds come in a wide variety of arrangements, many of which are quite different from what we see in our own solar system.
Some have giant planets that swing through the planetary systems in stretched-out, or “eccentric,” elliptical orbits, unlike the nearly circular orbits of planets like Jupiter and Saturn.
Astronomers think that many of these eccentric giant planets would act like “wrecking balls” in their planetary systems, disturbing the orbits of other, smaller planets. But that’s not always the case, according to a study published last week in The Astronomical Journal.
A giant exoplanet called HR 5183b, which orbits its host star in a stretched-out loop once every 75 years or so, wouldn’t disrupt the orbit of a small, rocky neighboring planet under the right conditions. And any stargazers on the hypothetical rocky planet’s surface would see the giant planet grow to be 15 times brighter than Venus in Earth’s sky when the giant planet swings by.Read More
A new collection of DNA from ancient Romans spanning 12,000 years shows how the population of the empire’s capital shifted along with its politics. Published in Science, the timeline is one of the first to examine what genetic information from archaeological digs says about the region after the time of hunter-gatherers and early farmers.
The analysis found that ancient Romans were from all over Europe, the Near East and northern Africa. “Rome was a cosmopolitan, melting-pot kind of place,” says study coauthor Jonathan Pritchard, a geneticist at Stanford University. “It doesn’t match how most people think about ancient cities.” It wasn’t until about 3,000 years ago that the inhabitants of Rome started to genetically resemble modern residents.Read More
A new analysis finds that 0.2 percent of all California methane emitters — individual pipes emitting or leaking the greenhouse gas — account for more than a third of the state’s methane production.
Nearly half of these methane sources, dubbed super-emitters, come from landfills. Dairies and the oil and gas industry account for a quarter of discharge sites each. Ideally, pinpointing these emitters will help shut down ones that are accidental methane emissions, like leaky pipes, says study coauthor Riley Duren, an engineer with the University of Arizona and NASA’s Jet Propulsion Laboratory. “A small number of super-emitters contribute disproportionately, and that suggests some low-hanging fruit.”Read More