
Warning! Nicotine poses special risks to teens
Even a single dose of nicotine during early teen years can start a life-long cycle of nicotine use and addiction.
Even a single dose of nicotine during early teen years can start a life-long cycle of nicotine use and addiction.
Primates are mammals that tend to have big brains, forward-facing vision, fingernails and flexible hands and feet.
A handful of rules can describe the route some object repeatedly takes around another in space. Calculating that path, however, can be quite complex.
Giant mammals and people thunder through our movies and books. But real mammals can only get so large before they can’t take the heat.
New observations from the Event Horizon Telescope reveal the chaotic region around the Milky Way’s central black hole, Sagittarius A*, in extreme detail.