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Researchers are learning more about how plants respond to "alarm signals" released by other plants that are under attack by herbivores. To warn conspecifics about predators, many animals issue alarms by vocalizing or emitting odors. In the case of…

Food packaging prevents contamination and extends the shelf-life of food products, making food safe and available to the public. Common food-packaging materials include metals, glass, paper, and plastics. Of these, metals, glass, and recyclable…

To bolster food security in a warming world, engineers are developing a coating that could better protect seeds, such as beans, from drought in semiarid regions. The coating mimics a mucilage-based hydrogel produced naturally by some seeds, such as…

Food waste occurs at all levels of the supply chain and beyond, from farm to table, for reasons ranging from spoilage to over-buying. The U.S. Department of Agriculture’s (USDA) Economic Research Service defines food waste as “the edible amount of…

Approximately 75% of flowering plants—including about a third of agricultural food crops—depend on the distribution of pollen by an array of animals known collectively as pollinators. These animals include insects such as bees and wasps…

Pasta comes in various sizes and shapes, ranging from long and flat (such as linguine and spaghetti) to short types in the shape of shells (conchiglie), corkscrews (fusilli), and many others. Shaped pastas contain a larger volume of air, resulting…

In recent years, researchers have made considerable progress toward producing renewable energy in the form of hydrogen fuel through the electrolysis of water. In the most basic electrolytic cell, an electric current drives a chemical reaction at two…

Black holes pack an extraordinary amount of mass into a small spatial volume, resulting in gravitational fields so powerful that not even light can escape. These extreme objects occur as two distinct populations in the universe. The first, called…

Atmospheric ozone plays a critical role in the biosphere by absorbing harmful ultraviolet radiation in the stratosphere—the layer of the atmosphere about 10 to 50 km (6 to 30 mi) above Earth’s surface. Since the adoption of the Montreal Protocol in…

In the future, will global demand for coffee outstrip supply? The International Coffee Organization thinks so, based on droughts in Central America, crop-destroying freezing weather in Brazil, and global climate change. In general, coffee is a very…

Forest fires are becoming more problematic across the globe. For example, climate change has extended fire season in the United States by about 80 days since 1970 because of extreme weather events, such as prolonged drought, according to the U.S.…

For the first time, researchers have used the spin rates of black holes in the wide-ranging and ongoing search for dark matter. A recent study proposed that if a certain kind of dark matter particle, known as an ultralight boson, existed in a…

A new study has offered a possible explanation for a mysterious drop in brightness exhibited by the star Betelgeuse, an event known as the Great Dimming. Betelgeuse is an aged, red supergiant star located relatively close to Earth and readily…

The discovery of gravitational waves in 2015 revolutionized astronomy by opening up an entirely new way of studying extreme cosmic phenomena. Now researchers have reported the first evidence for a previously theorized but never-before-seen kind of…

Astronomers have found oddly synchronized star formation rates in 36 dwarf galaxies scattered around the Milky Way Galaxy. These dwarf galaxies all showed declines in star formation rates starting around six billion years ago, and then showed…

After a 203-day journey covering 472 million kilometers (293 million miles), NASA's Perseverance rover successfully landed on Mars on February 18, 2021. Perseverance is the largest and most sophisticated machine to ever land on another world.…

Scrap tires are a common waste material, although markets do exist. According to the U.S. Tire Manufacturers Association, of the roughly 270 million scrap rubber tires generated each year in this country, about 100 million tires are used as fuel;…

Researchers at Northwestern University, Evanston, Illinois, USA, have developed a virus catcher of sorts—that is, a sticky and absorbent surface coating that traps droplets and aerosols (microdroplets) that land on the coating. Most often, fine…

In 2012, Voyager 1 became the first humanmade object to leave the solar system when the space probe traversed the heliopause—the boundary at which the outflow of plasma from the Sun, known as solar wind, gives way to the collective solar winds from…

Ample evidence—from lake-, river-, and delta-like geological features to aqueous mineralogy—supports the inference that Mars once had vast quantities of water pooling and flowing across its surface. A longstanding question has centered around what…

Researchers at Purdue University in Indiana, United States, have developed the whitest white paint on record, based on its ultrahigh reflection rating. By incorporating a pigment called barium sulfate (BaSO4) at the highest concentration possible,…

Wildfires are a natural phenomenon in many ecosystems, including forests along the U.S. Pacific West Coast, as natural fires serve to rejuvenate ecological communities. However, from mid-August through mid-September 2020, forests in California,…

Cosmochemists have discovered the oldest solid material known to exist on Earth. The material, stardust, consists of silicon carbide grains measuring around one micrometer in size. The grains date back approximately 7 billion years, or about 2.5…

Microplastics are raining down on national parks and other protected areas in the western United States at the rate of about 132 pieces of microplastic per square meter every day, according to a report in the journal Science (June 2020).…

In September 2020, researchers answered a longstanding question about why planetary nebulae display such a rich variety of shapes. Winds from aging stars produce planetary nebulae as the winds eject the stars' outer layers, shrouding the stars in…

Wildfires, also termed bushfires or forest fires, are currently devastating large swaths of land in Australia. Detrimental ecologic consequences of these uncontrolled combustions of forest fuels and vegetation are numerous. One of the most serious…

The American beech (Fagus grandifolia) is native to forest regions east of the Mississippi River and is a key tree species in the United States. In particular, it is very abundant from Ohio to the New England states. The tree is also found in the…

Many questions concerning the sustainable production of biofuels have emerged over recent years in terms of land and water use, pollution from fertilizer and pest-control chemicals, greenhouse-gas production, net energy production, and whether…

The nearest images of the Sun obtained to date have revealed a new phenomenon, dubbed campfires, which appear as small, bright flickers of light all over the Sun's surface. The Solar Orbiter, a European Space Agency spacecraft launched in February…

Astronomers have discovered the closest black hole on record, located 1,100 light-years away from our solar system. This black hole is part of the star system HR 6819, which consists of two bright, bluish stars. On a clear, dark night, these stars…

Obscured by a hazy atmosphere 100 times thicker than Earth's, Venus is a notoriously difficult world to study. Ground temperatures on Venus exceed 450°C (842°F)—enough to melt lead and to have quickly degraded the Soviet robotic landers last placed…

If you think converting seawater to fuels that can power ships is a fantasy, think again. Researchers at the U.S. Naval Research Laboratory in Washington, D.C., have, in fact, accomplished this feat. In addition, the U.S. Navy has received a patent…

Observations from the Hubble Space Telescope have solved a significant cosmic mystery that will help scientists better understand dark matter, an enigmatic substance theorized to outnumber normal matter at least fivefold. In 2018, astronomers were…

Astronomers have observed a galaxy from when the universe was only 1.4 billion years old that is remarkably similar to our Milky Way. Although lacking spiral arms like our galaxy, this distant galaxy does display a rotating disc and a starry,…

Fingerprint identification is a widely used forensic method for linking an individual to a crime scene. Investigators at a crime scene can find invisible (latent) fingerprints, which consist of natural skin oils, by "dusting" surfaces with carbon…

The ExoMars orbiter has detected a green glow emanating from excited oxygen molecules in the dayside atmosphere of Mars. The observations, gathered over a six-month period last year, confirm a four-decades-old prediction and represent the first time…

Heroin (C21H23NO5) is a white, crystalline powder synthesized from morphine, a natural alkaloid extracted from the seedpod of the Asian opium poppy plant, Papaver somniferum. It is a powerful opioid drug prepared by the addition of two acetyl groups…

A class of chemicals known as per- and polyfluoroalkyl compounds (PFAS) are particularly worrisome in the environment because they do not biodegrade. For this reason, scientists often refer to PFAS as “forever chemicals.” PFAS’s staying power…

Highly energetic light emitted by aged stars causes asteroids to keep spinning faster and faster to the point of disintegration, a new study finds. The findings help explain why white dwarf stars—remnants of Sunlike stars—often have metallic…

Naturally ventilating a house, such as by opening doors and windows, has long been considered an effective strategy for exhausting indoor air pollutants. However, according to researchers reporting in the journal Science Advances (February 2020),…

Famously durable, diamond is the hardest natural substance that occurs in any significant abundance on Earth. Yet according to a new study, on the nanoscale—a scale size of just billionths of a meter—diamond can, in fact, be bent and deformed. This…

Using old data from the NASA spacecraft MESSENGER, researchers have demonstrated how to measure the average lifetime of a neutron from space. This finding is important because, despite decades of efforts, physicists still cannot definitively say how…

With the launch of the next-generation James Webb Space Telescope in October 2021, astronomers will finally be able to perceive distant galaxies that host quasars—the most luminous objects in the universe. Quasars shine forth with the equivalent…

In a surprising find, researchers have detected phosphine (PH3) in the atmosphere of Venus. This poisonous, colorless, flammable gas is nonetheless considered a strong sign of life, or "biosignature." Biosignatures are gases or combinations of gases…

In December 2019, a new solar cycle started. Solar cycles are the roughly 11-year periods—documented going back nearly 270 years—over which the Sun’s magnetic activity peaks and troughs. This activity is marked by the formation of sunspots on the…

The supermassive black hole at the center of the Milky Way serves as a unique laboratory for testing predictions of general relativity. In a new study, researchers report that a long-studied star—called S2 or sometimes S-02—moves in a rosette-shaped…

After a 40-year search, astronomers have identified the first star shown to pulsate on only one side. Many kinds of stars, called variables, undergo natural pulsations, or periodic changes in brightness that are visible across the whole star. The…

Molten iron rains from the evening skies of an exoplanet designated WASP-76b, according to a new study. WASP-76b is a gas giant—a large planet with a vast gaseous envelope, like Jupiter—located about 390 light-years from Earth. Astronomers used an…

Stellar explosions known as supernovae may be behind several anomalous rises in radiocarbon captured in tree rings over the past 40,000 years, according to a recent study that adds mounting evidence to the hypothesis that supernovae can impact…

Researchers from Drexel University in Pennsylvania, USA, have synthesized conductive and layered 2D materials known as MXenes (pronounced maxenes) using a water-free process. In doing so, scientists have opened up potential uses of MXenes as…