Science news: nascent crystal formation observed, multiple Sahara greenings, volcano landslides, exoplanets discovered by high schoolers

Crystals have an incredible variety and still bear many secrets. The photo shows a rare Vanadinite from Marocco. Photo: Jan-Peter Kasper/FSURecent discoveries about our planet, its rocks, and other “stone” topics

The nucleation process, in which the atoms gather and form the smallest crystals, has been an important scientific phenomenon that has been widely studied since the late 1800s. This century-old mystery has been finally solved by an international joint research team which succeeded in observing the moment of the initial state of nanocrystal nucleation.

Overview of the area of study in Northern Africa and off the coast of Libya. The old river courses and the place where the sediment core was taken can also be seen. Credit: Axel TimmermannPast river activity in northern Africa reveals multiple Sahara greenings. The analysis of sediment cores from the Mediterranean Sea combined with Earth system models tells the story of several major environmental changes in North Africa over the last 160,000 years.

Scientists identified flank instability at Pacaya, an active volcano in Guatemala. Credit: Kirsten Stephens, Penn StateLandslides caused by the collapse of unstable volcanoes are one of the major dangers of volcanic eruptions. A method to detect long-term movements of these mountains using satellite images could help identify previously overlooked instability at some volcanoes, according to Penn State scientists.

Artist rendering of a five-planet system around TOI-1233 with a super-Earth (foreground) that could help solve mysteries of planet formation. The four innermost planets were discovered by high schoolers Kartik Pinglé and Jasmine Wright alongside researcher Tansu Daylan. Credit: NASA/JPL-Caltech16-year-old Kartik Pinglé and 18-year-old Jasmine Wright have co-authored a peer-reviewed paper in The Astronomical Journal describing the discovery of four new exoplanets about 200-light-years away from Earth. They participated in the research through the Student Research Mentoring Program (SRMP) at the Center for Astrophysics | Harvard & Smithsonian.