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Full title: Ancient bubbles in Australian rocks show early Earth's air weighed less than half today's atmosphere Air bubbles trapped in 2.7 billion-year-old Australian rock suggest the Earth's atmosphere weighed less than half of today and was much thinner than previously thought. Researchers analysed the size of air bubbles that formed at the top and bottom of lava flows along the Beasley River in Western Australia's Pilbara region almost three billion years ago and used the data to calculate the atmospheric pressure at the time. The results suggest that the air at the time exerted at most half the pressure...

From a Chinese rover on the moon and new spacecraft orbiting Mars, to private spaceships and the most powerful digital camera ever built, space will be practically buzzing with human activities in 2014. Here are some of the things to look out for when you're looking up next year: 7 Rosetta Spacecraft Artist Impression [Pin It] In August 2014, the ESA's Rosetta Spacecraft will rendezvous with Comet 67P/Churyumov-Gerasimenko and deploy its Philae lander, as seen in this artist's impression. Credit: ESA–C. Carreau/ATG medialab View full size image From a Chinese rover on the moon and new spacecraft orbiting Mars, to...

The moon maybe palely alone in the night sky today but according to scientists it is possible that the there was a second, smaller moon 4.4 billion years ago. A paper published in the journal Nature theorized that there was a smaller moon created in the same impact that created the moon. Astronomers, Martin Jutzi and Erik Asphaug of the University of California at Santa Cruz have long wondered why the moon had two incongruous sides, one smooth with flat plains and another side full of rugged mountains and craters. The astronomers started thinking that the mountainous region had been...

Most stars are born in clusters rather than singly, and there’s plenty of evidence that the Sun was too. For one thing, the material of the infant solar system (as preserved in the earliest meteorites) was enriched by fresh supernova debris from at least one very young, massive star (having 15 to 25 solar masses) that exploded less than 5 light-years away, no more than 2 million years after the Sun's formation. Today no such massive star exists within 300 light-years of the Sun. Clearly, the early solar system had stars close around it. But that was 4.57 billion years...

Scientists are beginning to sort out the stellar ingredients that produce a type 1a supernova, a type of cosmic explosion that has been used to measure the universe’s accelerating expansion. Two teams of researchers presented new data about these supernovas at the American Astronomical Society meeting on January 11. One team confirmed a long-held suspicion about the kind of star that explodes, and the second provided new evidence for what feeds that star until it bursts. “This is a confirmation of a decades-old belief, namely that a type 1a supernova comes from the explosion of a carbon-oxygen white dwarf,” said...

Fires can't burn in the oxygen-free vacuum of space, but guns can shoot. Modern ammunition contains its own oxidizer, a chemical that will trigger the explosion of gunpowder, and thus the firing of a bullet, wherever you are in the universe. No atmospheric oxygen required. The only difference between pulling the trigger on Earth and in space is the shape of the resulting smoke trail. In space, "it would be an expanding sphere of smoke from the tip of the barrel," said Peter Schultz an astronomer at Brown University who researches impact craters. The possibility of gunfire in space allows...

A hundred million years ago, a triple-star system was traveling through the bustling center of our Milky Way galaxy when it made a life-changing misstep. The trio wandered too close to the galaxy's giant black hole, which captured one of the stars and hurled the other two out of the Milky Way. Adding to the stellar game of musical chairs, the two outbound stars merged to form a super-hot, blue star. This story may seem like science fiction, but astronomers using NASA's Hubble Space Telescope say it is the most likely scenario for a so-called hypervelocity star, known as HE...

Thirty years ago, NASA scientists noticed that two of their spacecraft, Pioneer 10 and Pioneer 11, were veering off course slightly, as if subject to a mysterious, unknown force. In 1998, the wider scientific community got wind of that veering—termed the Pioneer anomaly—and took aim at it with incessant, mind-blowingly detailed scrutiny that has since raised it to the physics equivalent of cult status. Now, though, after spawning close to 1000 academic papers, numerous international conferences, and many entire scientific careers, this beloved cosmic mystery may be on its way out. Slava Turyshev, a scientist at the Jet Propulsion Laboratory...

Astronomers have confirmed the first discovery of an alien planet in our Milky Way that came from another galaxy, they announced today (Nov. 18). The Jupiter-like planet orbits a star that was born in another galaxy and later captured by our own Milky Way sometime between 6 billion and 9 billion years ago, researchers said. A side effect of the galactic cannibalism brought a faraway planet within astronomers' reach for the first time ever. [Illustration of the extragalactic planet] "This is very exciting," said study co-author Rainer Klement of the Max-Planck-Institut fur Astronomie (MPIA) in Heidelberg, Germany. "We have no...

Since the 1970s, a number of geostationary satellites have been placed in the so called "graveyard orbit," an orbit just above the GEO altitude, roughly 100 to 300 km. The sole purpose of this "burial" location is to remove expired satellites from the highly-congested GEO ring about the equator. Although most GEO satellite operators have not taken advantage of removing their old spacecraft, there are over 100 already there. This number will continue to grow, because some 20 GEO birds expire each year, and some of these will be sent to the graveyard. Thus, the total number of graveyard residents...

For spacecraft that zoom through the cosmos at thousands of miles per hour, calculating which one is traveling at the fastest speed is more complicated than simply clocking the first to cross the finish line. When space agencies calculate and establish speed records, these numbers need to be defined and qualified, because there can be more than one frame of reference. In other words, the speed of a spacecraft can be calculated relative to the Earth, the sun, or some other body. The record for the highest speed at which a spacecraft has launched and escaped from Earth's gravity is...

It's been a long wait—in some ways, more than 50 years—but in April 2010, the U.S. Air Force is scheduled to launch an Atlas V booster from Cape Canaveral, Florida, carrying the newest U.S. spacecraft, the unmanned X-37, to orbit. The X-37 embodies the Air Force's desire for an operational spaceplane, a wish that dates to the 1950s, the era of the rocket-powered X-15 and X-20. In other ways, though, the X-37 will be picking up where another U.S. spaceplane, NASA's space shuttle, leaves off.

It took humans thousands of years to explore our own planet and centuries to comprehend our neighboring planets, but nowadays new worlds are being discovered every week. To date, astronomers have identified more than 370 “exoplanets,” worlds orbiting stars other than the sun. Many are so strange as to confirm the biologist J. B. S. Haldane’s famous remark that “the universe is not only queerer than we suppose, but queerer than we can suppose.” There’s an Icarus-like “hot Saturn” 260 light-years from Earth, whirling around its parent star so rapidly that a year there lasts less than three days. Circling...

Sunspots are made of magnetism. The "firmament" of a sunspot is not matter but rather a strong magnetic field that appears dark because it blocks the upflow of heat from the sun's fiery depths. Without magnetism, there would be no sunspots [snip] According to Bill Livingston and Matt Penn of the National Solar Observatory in Tucson, Arizona, sunspot magnetic fields are waning. The two respected solar astronomers have been measuring solar magnetism since 1992. ... Extrapolating their data into the future suggests that sunspots could completely disappear within decades. [snip] "Whether this is an omen of long-term sunspot decline, analogous...

<p>WASHINGTON - In ``Star Wars,'' Darth Vader rules the ``dark side'' of a fantasy universe. In real life, astronomers are exploring the ``dark side'' of our own universe. They find it a mystifying place.</p> <p>According to a batch of new reports published in a special ``Welcome to the Dark Side'' issue of the journal Science, most of the cosmos cannot be seen, even with the most powerful telescopes. All but a tiny fraction of creation consists of two exotic, invisible ingredients called ``dark energy'' and ``dark matter.''</p>