A 2015 study led by John Worden of NASA’s Jet Propulsion Laboratory found that methane levels were unchanged for years, but increased sharply after 2006, growing by 25 million tons a year.

GaN-based light-emitting diodes with peripheral microhole arrays (PMA-LEDs) have been grown, and fabricated, on SiO 2 hexagonal pattern masks using selective metal-organic chemical vapor deposition.