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New Haven, Conn. — The Gondwana supercontinent underwent a 60-degree rotation across Earth’s surface during the Early Cambrian period, according to new evidence uncovered by a team of Yale University geologists. Gondwana made up the southern half of Pangaea, the giant supercontinent that constituted the Earth’s landmass before it broke up into the separate continents we see today. The study, which appears in the August issue of the journal Geology, has implications for the environmental conditions that existed at a crucial period in Earth’s evolutionary history called the Cambrian explosion, when most of the major groups of complex animals rapidly...

Skywatchers have been trying to gauge the sun-Earth distance for thousands of years. In the third century BC, Aristarchus of Samos, notable as the first to argue for a heliocentric solar system, estimated the sun to be 20 times farther away than the moon. It wasn't his best work, as the real factor is more like 400. By the late 20th century, astronomers had a much better grip on this fundamental cosmic metric -- what came to be called the astronomical unit. In fact, thanks to radar beams pinging off various solar-system bodies and to tracking of interplanetary spacecraft, the...

University of Arizona scientists have uncovered a curious case of missing asteroids. The main asteroid belt is a zone containing millions of rocky objects between the orbits of Mars and Jupiter. The scientists find that there ought to be more asteroids there than researchers observe. The missing asteroids may be evidence of an event that took place about 4 billion years ago, when the solar system's giant planets migrated to their present locations. UA planetary sciences graduate student David A. Minton and UA planetary sciences professor Renu Malhotra say missing asteroids is an important piece of evidence to support an...

June 5, 2006 | Evidence continues to mount that planets can form around very-low-mass objects. In fact, planets might even form around objects that are so low in mass that they themselves could be considered "planets." The latest results, reported at this week's American Astronomical Society meeting in Calgary, Alberta, come from groups led by Ray Jayawardhana (University of Toronto, Canada) and Subhanjoy Mohanty (Harvard-Smithsonian Center for Astrophysics).

(PhysOrg.com) -- A new theory suggests the Moon was formed after a natural nuclear explosion in the Earth's mantle rather than after the impact of a massive object with the Earth, as previously thought. The problem with the impact hypothesis is that simulations calculate the Moon should be composed of 80% impactor and 20% Earth, whereas in fact the isotope ratios of light and heavy elements found in Moon rocks so far examined are virtually identical to those on Earth. The fission hypothesis is an alternative explanation for the formation of the moon, and it predicts similar isotope ratios in...

Scientists have discovered significant amounts of water on the moon—about twice the quantity seen in the Sahara Desert—a finding that may bolster the case for establishing a manned base on the lunar surface. In an audacious experiment last year, the National Aeronautics and Space Administration slammed a spent-fuel rocket into a lunar crater at 5,600 miles an hour, and then used a pair of orbiting satellites to analyze the debris thrown off by the impact. They discovered that the crater contained water in the form of ice, plus a host of other resources, including hydrogen, ammonia, methane, mercury, sodium and...

Water on the moon? Scientists used to think it was as dry as, well, lunar dust. But after a year of analysis NASA today announced that its LCROSS lunar-impact probe mission found

Evidence that water came to Earth during its formation from cosmic dust, rather than following later in asteroids, has been shown by a group of international scientists. The origin of the abundant levels of water on Earth has long been debated with the main differences in the theories being the nature of the material that carries the water, and whether the water came during or after planet formation. Now, Nora de Leeuw at University College London, UK, and colleagues have used molecular-level calculations to prove that dissociative chemisorption of water onto the surface of olivine rich minerals, such as forsterite,...

It's an unlikely marriage between state-of-the-art and 40-year-old technology that has yielded extraordinary results. Signals from seismic sensors left on the lunar surface by Apollo astronauts in 1971 have revealed that the Moon has a liquid core similar to Earth's. Scientists at Nasa applied contemporary seismological techniques to the data being emitted from sensors placed by their colleagues during the U.S. space program's heyday....

You can't breathe on the moon, but now you can smell it. A Scottish printmaker has released a series of works that publicize a fact known to astronauts for decades: The moon smells like gunpowder. Apprentice printer Sue Corke worked with flavorist Steven Pearce of Omega Ingredients and Apollo 16 astronaut Charles M. Duke Jr. to create "scratch-and-sniff" moon prints. NASA has known since the 1970s about the gunpowder-like odor of Earth's natural satellite. Even though there's no air on the moon, one moonwalker, Apollo 14 lunar module pilot Edgar D. Mitchell, confirmed to AOL News that the moon smells...

It's a classic image from every youngster's science textbook: a cutaway image of Earth's interior. The brown crust is paper-thin; the warm mantle orange, the seething liquid of the outer core yellow, and at the center the core, a ball of solid, red-hot iron. Now a new theory aims to rewrite it all by proposing the seemingly impossible: Earth has not one but two inner cores. The idea stems from an ancient, cataclysmic collision that scientists believe occurred when a Mars-sized object hit Earth about 4.45 billion years ago. The young Earth was still so hot that it was mostly...

STEREO Hunts for Remains of an Ancient Planet near Earth April 9, 2009: NASA's twin STEREO probes are entering a mysterious region of space to look for remains of an ancient planet which once orbited the Sun not far from Earth. If they find anything, it could solve a major puzzle--the origin of the Moon. The name of the planet is Theia," says Mike Kaiser, STEREO project scientist at the Goddard Space Flight Center. "It's a hypothetical world. We've never actually seen it, but some researchers believe it existed 4.5 billion years ago—and that it collided with Earth to form...

Clara Moskowitz The solar system might once have had another planet named Theia, which may have helped create our own planet's moon. Now two spacecrafts are heading out to search for leftovers from this rumored sibling, which would have been destroyed when the solar system was still young. "It's a hypothetical world. We've never actually seen it, but some researchers believe it existed 4.5 billion years ago — and that it collided with Earth to form the moon," said Mike Kaiser, a NASA scientist at the Goddard Space Flight Center in Maryland...

April 9, 2009: NASA's twin STEREO probes are entering a mysterious region of space to look for remains of an ancient planet which once orbited the Sun not far from Earth. If they find anything, it could solve a major puzzle--the origin of the Moon. "The name of the planet is Theia," says Mike Kaiser, STEREO project scientist at the Goddard Space Flight Center. "It's a hypothetical world. We've never actually seen it, but some researchers believe it existed 4.5 billion years ago—and that it collided with Earth to form the Moon." Right: An artist's concept of one of the...

Line up Mercury, Venus, Earth and Mars according to their distance from the sun and you'll see their size distribution is close to symmetrical, with the two largest planets between the two smallest. That would be no coincidence -- if the pattern emerged from a debris ring around the sun. Brad Hansen of the University of California, Los Angeles, built a numerical simulation to explore how a ring of rocky material in the early solar system could have evolved into the planets. He found that two larger planets typically form near the inner and outer edges of the ring, corresponding...

Neptune's largest moon, Triton, was originally a member of a duo orbiting the Sun but was kidnapped during a close encounter with Neptune, a new model suggests. Triton is unique among large moons in that it orbits Neptune in a direction opposite to the planet's rotation, which long ago led scientists to speculate that the moon originally orbited the Sun. But until now, no convincing theory for how Triton paired with Neptune existed. Gravity might have pulled Triton away from its companion to make it an orbiting satellite of Neptune, researchers report in a new study published in the May...

This high tide is bound to wash away more than just your sand castle. A new study has found that bulges in Earth's crust — solid Earth tides — trigger about 1 percent of earthquakes. As Earth and the moon grind through their gravitational ballet, our planet gets tugged hard near the equator. The force is so strong that as the moon passes overhead each day, it pulls Earth's surface up 11.8 inches.

Without the Moon, there would have been no life on Earth. Four billion years ago, when life began, the Moon orbited much closer to us than it does now, causing massive tides to ebb and flow every few hours. These tides caused dramatic fluctuations in salinity around coastlines which could have driven the evolution of early DNA-like biomolecules. This hypothesis, which is the work of Richard Lathe, a molecular biologist at Pieta Research in Edinburgh, UK, also suggests that life could not have begun on Mars. According to one theory for the origin of life, self-replicating molecules such as DNA...

Asteroid Vesta: The 10th Planet? Discovery Brightens Odds of Finding Another Pluto Nemesis: The Million Dollar Question HOUSTON, TEXAS -- Our solar system may have had a fifth terrestrial planet, one that was swallowed up by the Sun. But before it was destroyed, the now missing-in-action world made a mess of things. Space scientists John Chambers and Jack Lissauer of NASA's Ames Research Center hypothesize that along with Mercury, Venus, Earth, and Mars -- the terrestrial, rocky planets -- there was a fifth terrestrial world, likely just outside of Mars's orbit and before the inner asteroid belt. Moreover, Planet V...

December 23, 2005: NASA scientists have observed an explosion on the moon. The blast, equal in energy to about 70 kg of TNT, occurred near the edge of Mare Imbrium (the Sea of Rains) on Nov. 7, 2005, when a 12-centimeter-wide meteoroid slammed into the ground traveling 27 km/s. "What a surprise," says Marshall Space Flight Center (MSFC) researcher Rob Suggs, who recorded the impact's flash. He and colleague Wes Swift were testing a new telescope and video camera they assembled to monitor the moon for meteor strikes. On their first night out, "we caught one," says Suggs.