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At first glance, magnetite appears to be a rather inconspicuous grey mineral. But on an atomic scale, it has remarkable properties: on magnetite, single metal atoms are held in place, or they can be made to move across the surface. Sometimes several metal atoms on magnetite form small clusters. Such phenomena can dramatically change the chemical activity of the material. Atomic processes on the magnetite surface determine how well certain metal atoms can serve as catalysts for chemical reactions.

Scientists at TU Wien (Vienna), together with colleagues from Utrecht University, can now watch single platinum atoms form tiny clusters. Carbon monoxide plays a dual role in this process: It allows single platinum atoms to move and form pairs, and then it holds these pairs together for a long time. Only by increasing the temperature can the pair-bonds between platinum atoms can be broken.

The Zika virus poses a negligible health threat to the international community during the summer Olympic Games that begin next month in Rio de Janeiro, Brazil, according to researchers at Yale School of Public Health (YSPH).

In a worst-case scenario, an estimated 3 to 37 of the thousands of athletes, spectators, media, and vendors traveling to Rio for the Olympics will bring the Zika virus back to their home countries, the researchers concluded.

Solar cells have been manufactured already for a long from inexpensive materials with different printing techniques. Especially organic solar cells and dye-sensitized solar cells are suitable for printing.

-We wanted to take the idea of printed solar cells even further, and see if their materials could be inkjet-printed as pictures and text like traditional printing inks, tells University Lecturer Janne Halme.

When light is absorbed in an ordinary ink, it generates heat. A photovoltaic ink, however, coverts part of that energy to electricity. The darker the color, the more electricity is produced, because the human eye is most sensitive to that part of the solar radiation spectrum which has highest energy density. The most efficient solar cell is therefore pitch-black.

One hundred and thirty years ago, the volcano Krakatoa erupted in what is now Indonesia, unleashing a cataclysm locally and years of cool temperatures and rain globally. On the far side of the world, a bumper crop of saguaro cacti were getting their start in life in Arizona's Sonoran Desert. Many of the large exemplars of the famous cacti standing spiny and tall with arms akimbo in the Southwest today started their lives in the shadow of the 1883 eruption.

Biogeographer Taly Drezner believes that distant volcanic paroxysms and the emergence of bountiful saguaro age-mate cohorts are connected. Volcanic climate perturbations that delivered disastrously cold and stormy weather to much of the Northern Hemisphere generated a combination of conditions in the Sonoran Desert that were just right for the delicate young cacti. Drezner will present her research on the first known example of regional population effects on a species from volcanic eruptions in distant parts of the world on 9 August 2016 at the 101st Annual Meeting of the Ecological Society of America, gathering this year in Fort Lauderdale, Florida.

Solar Impulse 2 touched down in Abu Dhabi today, becoming the first fuel-free plane to successfully circumnavigate the globe. OK, so the 22,000-mile trip took a minute: The solar-powered bird lifted off from the same city in March 2015. But despite a few setbacks, the plane and Swiss pilot Bertrand Piccard (who took shifts with fellow flyer André Borschberg) touched down without incident.

Solar Impulse 2 is a seriously nifty machine. Its 236-foot wingspan makes it wider than a Boeing 747, but the thing is just 5,000 pounds. 17,000 rigid, photovoltaic panels charge four uber-efficient batteries, which make up nearly a third of the weight. Its four 17.4-horsepower motors definitely aren’t the fastest: The plane tops out around 90 mph, and traveled at an average of 38 mph across the Pacific. (Yeah, we’d honk at it on the highway, too.)