A Chinese astronomer has helped uncover the exuberant "teenage years" of the Milky Way when it merged with a satellite galaxy, consumed plenty of hydrogen gas and formed many stars, according to a study published in the journal Nature on Thursday.
What do a 58-year-old pig farm worker from Hubei province and Iron Man have in common? They both have futuristic "artificial heart" devices made of metal and magnets to keep them alive.
Throughout history, dentists around the globe have been using a variety of materials to repair cracked and damaged teeth, including beeswax, alloys, ceramics and resins.
