ALTHOUGH it is well known that Population I objects in the galaxy move in approximately circular orbits, the detailed situation is not clear. Anomalies of various types have been found, non-circular ...

Hydrogen is projected to account for 16% of road transport, potentially competing with battery-powered electric vehicles. Challenges in hydrogen production efficiency and sourcing remain, with ...

Twelve colors and counting. The terminology associated with hydrogen—specifically, the use of color descriptors such as green, blue and gray—has become widespread in discussions about renewable energy ...