radioactive cloud

"It turns out that this radioactive cloud, that kilonova afterglow, which had all these nuclear synthetic fingerprints in it, is the signature of a binary merger. The excitement comes from using the Webb to identify a chemical fingerprint that we had expected for short bursts and seeing it inside a long burst."

Many local officials have fallen into line, and last week communities across central Ukraine snapped into action and held emergency drills to prepare themselves for a disaster that the officials believe could spread a radioactive cloud over the entire area.

While Chinese officials presumably fear North Korea’s nuclear tests could go awry, creating a radioactive cloud, it appears perfectly happy to have the North unsettling the United States and its allies with regular missile tests.

Then a radioactive cloud drifted toward Europe, and the truth could no longer be hidden.

April 1986 - Explosion at Chernobyl nuclear reactor spreads radioactive cloud across Europe.