Lyman-alpha wavelengths are particularly susceptible to absorption by neutral hydrogen, clueing astronomers in to the fact that there is very little of it left within and around this galaxy. One ...

Some atoms and molecules in space emit radio waves at particular frequencies. Hydrogen atoms emit at 1420 MHz (a wavelength of 21 cm). Hydroxyl molecules, composed of one atom of hydrogen and one atom ...

A group has developed a low-cost method to produce carbon-free 'green' hydrogen via solar-powered electrolysis of seawater. A happy byproduct of the process? Potable water.