'Mini-Neptune' exoplanets may have smoggy atmospheres similar to diesel exhaust

The astronauts circling Earth on the Artemis mission sent back beautiful clear photos of the continents, clouds, and oceans. But we might be the exception. Many planets in the universe may be hazed in clouds of soot, according to a new study by University of Chicago scientists. Their analysis explains a curious trend seen by astronomers training telescopes on distant planets beyond our own solar system. Many of these worlds had atmospheres that returned strangely featureless readings.