Hawaii is well known to have been created from volcanic activity, and the geologic hotspot below the islands is the most studied in the world.
Space is probably infinite, but we can see only the part that contains stars or galaxies whose light has been able to reach us, says Francis Halzen, a professor of physics. The universe originated about 13.7 billion years ago with the Big Bang, so light cannot have been traveling for more than 13.7 billion years. [...]
You’ve seen photos of lunar and solar eclipses, or maybe you’ve even been present for one yourself, but have you ever seen an eclipse of the Earth? Astronaut Bill McArthur and flight engineer Valery Tokarey snapped this photo from aboard the International Space Station on March 29, 2006 during a total eclipse of the sun. [...]
It depends on the kind of lifestyle those people enjoy, says Lisa Naughton, a UW-Madison professor of geography and environmental studies. The late 18th century English economist Thomas Malthus – one of the first to express concern about overpopulation – observed that there should be no more people in a country than can “daily enjoy [...]
“The answer is rooted in the fact that our planet is a ‘living’ planet, which is still cooling,” says Laurel Goodwin, professor of geology at UW-Madison. She describes Earth as a series of shells, like a peanut M&M. “The candy shell is the crust, on which we live. The chocolate beneath is the mantle, and [...]
Moon was formed by impact of Theia with Earth. How do we know this, and why might we care?