Collisions between liquid drops and surfaces, or other drops, happen all the time. For example, small water drops in clouds collide with each other to form larger drops, which can eventually fall and impact on a solid, like your car windscreen. Drops can behave differently after the point of collision, some make a splash, some coat the surface cleanly, and some can even bounce like a beach ball. In the article, published today in Physical Review Letters, researchers from the University of Warwick have found an explanation for experimental observations that some droplets bounce....

On November 22, 2014, astronomers spotted a rare event in the night sky: A supermassive black hole at the center of a galaxy, nearly 300 million light-years from Earth, ripping apart a passing star. The event, known as a tidal disruption flare, for the black hole’s massive tidal pull that tears a star apart, created a burst of X-ray activity near the center of the galaxy. Since then, a host of observatories have trained their sights on the event, in hopes of learning more about how black holes feed....

Our solar system exhibits a remarkably orderly configuration: The eight planets orbit the sun much like runners on a track, circling in their respective lanes and always keeping within the same sprawling plane. In contrast, most exoplanets discovered in recent years — particularly the giants known as “hot Jupiters” — inhabit far more eccentric orbits. Now researchers at MIT, the University of California at Santa Cruz and other institutions have detected the first exoplanetary system, 10,000 light years away, with regularly aligned orbits similar to those in our solar system....

A new method for visualizing breath that is exhaled while someone is speaking or singing could provide important new insights into how diseases such as COVID-19 spread and the effectiveness of face masks. “Scientists believe the SARS-CoV-2 virus is primarily spread through respiratory droplets that can be carried in the breath or expelled through coughing or sneezing,” said Thomas Moore from Rollins College, who performed the research. “But it is also transmitted by airborne aerosols, which are small particles that remain in the air longer than the larger droplets....

Since the human genome was first sequenced in 2001, scientists have puzzled over swathes of our DNA that despite apparently lacking function are made into ribonucleic acid (RNA) by the cell. Why make RNA at all when it is not then used to make proteins, which perform fundamental biological tasks? Perhaps these so-called non-coding RNAs perform critical, but as yet unknown, tasks? Scientists from the Universities of Bath, Oxford, and Edinburgh have now identified one such non-coding RNA, called Paupar, which influences how healthy brains develop during early life....

A project led by the Max Planck Institute for the Science of Human History has discovered a fossilized finger bone of an early modern human in the Nefud Desert of Saudi Arabia, dating to approximately 90,000 years ago. The discovery, described in Nature Ecology and Evolution, is the oldest directly dated Homo sapiens fossil outside of Africa and the Levant and indicates that early dispersals into Eurasia were more expansive than previously thought....

The study found that variations in running performance among a group of lab mice were mainly caused by the presence of specific gut bacterial species in the mice with better performance. The researchers identified that this effect is linked to the small molecules called metabolites that these bacteria produce. These metabolites activate sensory nerves in the gut which in turn, increase activity in a brain region that controls motivation during exercise....

Researchers analyzed daily low temperatures and infection rates in 50 Northern Hemisphere countries to quantify their effect on SARS-CoV-2 transmission. The SARS-CoV-2 pandemic has caused tremendous upheaval, leading to more than 2.3 million deaths worldwide and 465,000 in the United States. Understanding the impact of seasonal temperature changes on transmission of the virus is an important factor in reducing the virus’s spread in the years to come. SARS-CoV-2 belongs to a large family of human coronaviruses, most of which are characterized by increased transmission in cooler, less humid months and decreased transmission in warmer, more humid months....

Scientists have succeeded in cultivating an archaeon that converts oil into methane. They describe how the microbe achieves the transformation and that it prefers to eat rather bulky chunks of food. Microorganisms can convert oil into natural gas, i.e. methane. Until recently, it was thought that this conversion was only possible through the cooperation of different organisms. In 2019, Rafael Laso-Pérez and Gunter Wegener from the Max Planck Institute for Marine Microbiology suggested that a special archaeon can do this all by itself, as indicated by their genome analyses....

Ninety percent of adolescent girls report having menstruation pain. Most people manage their pain with over-the-counter medicines, but with limited positive results. Diets high in omega-3 fatty acids and low in processed foods, oil, and sugar have been shown to lower inflammation, a key contributor to menstrual pain. This study sought to investigate the influence of diet on menstrual pain and discover which foods contribute to it and which might alleviate it....

BOSS, the Baryon Oscillation Spectroscopic Survey, is mapping a huge volume of space to measure the role of dark energy in the evolution of the universe. BOSS is the largest program of the third Sloan Digital Sky Survey (SDSS-III) and has just announced the first major result of a new mapping technique, based on the spectra of over 48,000 quasars with redshifts up to 3.5, meaning that light left these active galaxies up to 11....

“We found that specific nanoparticles – titanium dioxide and silicon dioxide – ordinarily used in food may negatively affect intestinal functionality,” said senior author Elad Tako, associate professor of food science at Cornell. “They have a negative effect on key digestive and absorptive proteins.” In their study, the research team administered human-equivalent doses of titanium dioxide and silicon dioxide in the Tako laboratory’s in vivo system, which provides a health response that closely resembles that of the human body....

Study suggests parts of the Sierra Nevadas formed in a “geologic instant,” more than twice as fast as previously thought. Although we can’t see it in action, the Earth is constantly churning out new land. This takes place at subduction zones, where tectonic plates crush against each other and in the process plow up chains of volcanos that magma can rise through. Some of this magma does not spew out, but instead mixes and morphs just below the surface....

In a study that looked at suicide deaths during 2020’s first wave of the COVID-19 pandemic in Maryland, Johns Hopkins Medicine researchers found that, contrary to general predictions of suicides skyrocketing, suicides in the overall population actually dropped, relative to previous years. However, the researchers also discovered that suicide deaths increased dramatically among Black Marylanders during the same period. The researchers say that their findings, published on December 16, 2020, in JAMA Psychiatry, highlight the importance of timely identification of high-risk groups and vulnerable populations to reduce suicide numbers....

The origins of the junk are in dispute. Some say it’s a spent booster from a Chinese rocket. Others say it’s from a SpaceX rocket. So far, nobody is claiming it. Bill Gray was the first one to spot the object. Gray writes the Project Pluto software that tracks Near-Earth Objects (NEOs.) Initially, Gray said the object was the second stage from NASA’s DISCOVR spacecraft launched in 2015. That was a SpaceX Falcon 9 upper stage....

Crew-2 joins Expedition 65 crew of crew of Shannon Walker, Michael Hopkins, Victor Glover, and Mark Vande Hei of NASA, as well as Soichi Noguchi of JAXA and Roscosmos cosmonauts Oleg Novitskiy and Pyotr Dubrov. The crew members first opened the hatch between the space station and the pressurized mating adapter at 7:05 a.m. EDT then opened the hatch to Crew Dragon. Earlier NASA astronauts Shane Kimbrough and Megan McArthur, along with JAXA (Japan Aerospace Exploration Agency) astronaut Akihiko Hoshide, and ESA (European Space Agency) astronaut Thomas Pesquet arrived at the International Space Station Saturday, as the SpaceX Crew Dragon Endeavour docked to the complex at 5:08 a....

Eta Carinae is a binary system of superlatives, consisting of two blue giants, one about 100 times, the other about 30 times the mass of our sun. The two stars orbit each other every 5.5 years in very eccentric elliptical orbits, their separation varying approximately between the distance from our Sun to Mars and from the Sun to Uranus. Both these gigantic stars fling dense, supersonic stellar winds of charged particles out into space....

For 30 years, University of Tokyo Associate Professor Hisayoshi Nozaki has traveled an hour west of Tokyo to visit the Sagami River and collect algal samples to understand how living things evolved different sexes. Through new analysis of samples collected in 2007 and 2013 from dam lakes along the river, Lake Sagami and Lake Tsukui, researchers identified a species of freshwater algae that evolved three different sexes, all of which can breed in pairs with each other....

How many rings do you see in this new image of the galaxy Messier 94, also known as NGC 4736? While at first glance one might see a number of them, astronomers believe there is just one. This image was captured in infrared light by NASA’s Spitzer Space Telescope. Historically, Messier 94 was considered to have two strikingly different rings: a brilliant, compact band encircling the galaxy’s core, and a faint, broad, swath of stars falling outside its main disk....

If the idea of flying on battery-powered commercial jets makes you nervous, you can relax a little. Researchers have discovered a practical starting point for converting carbon dioxide into sustainable liquid fuels, including fuels for heavier modes of transportation that may prove very difficult to electrify, like airplanes, ships, and freight trains. Carbon-neutral reuse of CO2 has emerged as an alternative to burying the greenhouse gas underground. In a new study published today in Nature Energy, researchers from Stanford University and the Technical University of Denmark (DTU) show how electricity and an Earth-abundant catalyst can convert CO2 into energy-rich carbon monoxide (CO) better than conventional methods....