A mysterious thick fog has swept across the US with multiple communities reporting a "burning chemical-like smell," akin to a similar event last year when 70 million people were engulfed in dense fog.

Once the air temperature cools enough to equal the dew point temperature, condensation forms and creates a blanket-like thick fog formation. Not limited to the San Francisco Bay Area, advection ...

The surprise finding is challenging researchers to explain how this light could have pierced the thick fog of neutral hydrogen that filled space at that time. A key goal of the NASA/ESA/CSA James ...