The tooth is one of the few physical remains known of Denisovans, a sister lineage to Neanderthals who until now had been known only from scrappy dental and bone fossils from a single site in Siberia and one in the Himalayas.
Researchers had no idea if anything would sprout in the harsh moon dirt and wanted to see if it could be used to grow food by the next generation of lunar explorers.
Scientists call it the “gentle giant” of the Milky Way: a massive black hole called Sagittarius A*. It’s about 4 million times larger than the sun in our solar system. NBC News’ Tom Costello explains the history behind the monumental discovery and the facts about this phenomenon.
The inaugural Aspen Ideas: Climate conference, a four-day event that began Monday, attracted hundreds of scientists, policymakers, activists and business leaders.
"It will degrade our entire forest," a scientist and environmentalist said about the train project through jungle, cave systems and Mayan archaeological sites.