Science & Technology
Deteriorated DNA from microbes, frozen for millions of years in the Antarctic ice, shows that organisms could not have survived the bombardment of cosmic radiation during deep space travel from outside the solar system, said Paul Falkowski, a Rutgers biologist and oceanographer.
The answer starts with the forces that formed our solar system.
A fledgling star gathers a disk of dust and gas around itself, said Kevin Luhman, an assistant professor of astronomy at Penn State. As things coalesce, the star's gravitational orbit sets that dust and gas to spinning. "Any clump that forms within that disk is going to naturally have some sort of rotation," Luhman said.
Researchers had traditionally assumed that Europe was settled in waves starting around two million years ago, as our ancient ancestors-collectively known as hominids-came over from Africa.
But the shapes of teeth from a number of hominid species suggest that arrivals from Asia played a greater role in colonizing Europe than hominids direct from Africa.
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| © Johns Hopkins University Applied Physics Laboratory |
| The device pictured above is the second prototype in the U.S. military's ambitious prosthetics project to build a bionic arm. |
Turns out he wasn't so lonely. While we said in the Q&A that NASA was doing little to protect us from an asteroid crash, it turns out the agency's been working on an anti-asteroid nuclear missile.
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Intelligent Optical Systems, Inc., of Torrance, Calif., has been granted a contract by the Department of Homeland Security to develop what it calls the "LED Incapacitator," according to a DHS online newsletter.
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| ©DHS |
The clashing galaxies, spotted by NASA's Spitzer Space Telescope, will eventually merge into a single, behemoth galaxy up to 10 times as massive as our own Milky Way. This rare sighting provides an unprecedented look at how the most massive galaxies in the universe form.
"Most of the galaxy mergers we already knew about are like compact cars crashing together," said Kenneth Rines of the Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass. "What we have here is like four sand trucks smashing together, flinging sand everywhere." Rines is lead author of a new paper accepted for publication in Astrophysical Journal Letters.
Collisions, or mergers, between galaxies are common in the universe. Gravity causes some galaxies that are close together to tangle and ultimately unite over a period of millions of years. Though stars in merging galaxies are tossed around like sand, they have a lot of space between them and survive the ride. Our Milky Way galaxy will team up with the Andromeda galaxy in five billion years.









