News
- Physics
Electrons get a crack at the nucleus
As long suspected but never before shown, electrons orbiting an atom can directly excite the atom's nucleus.
- Earth
A late arrival for platinum and gold?
An extraterrestrial source may explain why Earth's mantle holds more platinum, gold, and certain other elements than it should.
- Earth
Strange crystal birth found in mine
Deep in a Wisconsin mine, researchers have uncovered a new way for crystals to grow in nature.
- Health & Medicine
Old polio vaccine free of HIV, SIV
Three laboratories analyzing remaining samples of polio vaccine used in the late 1950s find that none contains any human or simian immunodeficiency virus, or chimpanzee DNA—making polio vaccine unlikely to be the cause of the initial HIV outbreak in central Africa.
