07/28/2010
07:00 AM
Origins: Going Back to Where the Story Really Starts (preview)
We are always telling stories about the world, the universe, ourselves. It helps to make sense of things. But sometimes, through familiarity or neglect, we get lost. We forget where a story really starts, losing sight of where it’s headed. What is biodiversity? Are electric cars new? Even the well-worn tale of human origins is missing a key chapter: how a small band of hunter-gatherers survived a climate disaster, becoming ancestors of us all. Here we provide the surprising origins of some strange and familiar things.
All In The Family [More]
Hunter-gatherer – Biodiversity – Human evolution – Fiction – Arts
07/23/2010
08:36 AM
Superstar Is the Remnant of a Three-Star System Mangled by a Black Hole
Here’s what scientists think happened, oh, about a hundred million years ago. There was this three-star system. The three linked stars were strolling through the Milky Way but got too close to the giant black hole at the center. The hole swallowed one of those stars and hurled away the other two. Those two careening stars merged to form one super-hot, incredibly fast-moving blue star, which is now on the very outskirts of the Milky Way.
And here’s how scientists came up with that dramatic tale, which they just published in Astrophysicial Journal Letter s. [Warren Brown et al., http://bit.ly/aSLafm ]
[More]
Milky Way – Black hole – Star – Astronomy – Galaxies
07/22/2010
12:01 PM
When should a scientist’s data be liberated for all to see?
When researchers make an exciting discovery, the data behind it are often closely guarded until they can be examined, developed and then revealed–at least in part–in a peer-reviewed journal with all of the proverbial fanfare. [More]
Peer review – Journals – Health – Medicine – Medical Specialties
07/16/2010
01:36 PM
Gas-Giant Planet May Sport Cometlike Tail
Whaddya get when you cross a planet with a comet? Well, HD 209458 b looks like a candidate. It’s a gas giant planet also called Osiris, and it’s orbiting so close to its star that some of its atmosphere gets blown away by the stellar wind. Astronomers think that it may then have a tail like a comet’s.
The researchers studied the odd object using the Hubble Space Telescope and reported their finding in the July 10th issue of The Astrophysical Journal . [Jeffrey Linsky et al., http://bit.ly/b77vzS ] [More]
Hubble Space Telescope – HD 209458b – Comet – Gas giant – Astrophysical Journal
07/13/2010
08:00 AM
Perturbing Discovery: Does an Exoplanet’s Orbital Oddity Reveal a Neighboring World?
Astronomers are uncovering newfound planets in orbit around other stars at a meteoric rate these days. The tally of known planets outside the solar system now stands at more than 450, of which about 50 have been discovered just this year. That pace promises to increase as NASA’s Kepler mission carries out its multiyear survey of a large patch of stars; the campaign has already located several hundred planetary candidates for follow-up study and confirmation. [More]
Solar System – NASA – Extrasolar planet – Kepler Mission – Astronomy
07/07/2010
08:00 AM
Luminary Lineage: Did an Ancient Supernova Trigger the Solar System’s Birth?
One star dies, another is born. The remains of the old are gathered up, at least in some small measure, to become part of the new. That is the astronomical circle of life, the reason that stars have evolved through the eons, each generation incorporating new elements synthesized in the stars that came before. Unlike the earliest stars of hydrogen and helium, stars nowadays contain heavier elements passed down to them by their predecessors, such as carbon, iron and oxygen. [More]
07/03/2010
08:00 AM
Study shows how sunlight on Titan yields life-precursor compounds
Titan, Saturn’s largest moon, does not harbor alien life as far as anyone knows, but the prospects for extraterrestrial biology there are about as good there as anywhere else in the solar system. [More]
Saturn – Titan – Solar System – Extraterrestrial life – Astronomy
07/01/2010
02:15 PM
Getting the Lead out: New Look at Apollo 17 Moon Sample Reveals Graphite Delivered by a Lunar Impactor
Humans have not set foot on the moon since December 14, 1972, when astronauts Eugene Cernan and Harrison Schmitt of the Apollo 17 mission departed the lunar surface to return home. Thankfully, Cernan and Schmitt, a trained geologist , collected 110 kilograms of lunar material–the largest-ever haul of moon rocks and soil–before heading for Earth. [More]
Earth – Moon – Apollo 17 – Eugene Cernan – Space
06/30/2010
10:00 PM
An Extra Quiet Sun
Miami–In rough terms, the sun’s activity ebbs and flows in an 11-year cycle, with flares, coronal mass ejections, and other energetic phenomena peaking at what is called solar maximum and bottoming out at solar minimum. Sunspots, markers of magnetic activity on the sun’s surface, provide a visual proxy for the cycle’s evolution; they appear in droves at maximum and all but disappear at minimum. But the behavior of our host star is not as predictable as all that–the most recent solar minimum of late 2008 was surprisingly quiet and prolonged.
Solar physicists have offered a number of mechanisms to shed light on the solar cycle. Beyond improving fundamental scientific understanding, better predictions of solar behavior would help safeguard against electrical grid disruptions, damage to Earth-orbiting satellites and radiation threats to astronauts. In a press conference at the semiannual meeting of the American Astronomical Society in May, researchers laid out different approaches to tracking and predicting the sun’s activity, but the final explanation–or, more likely, explanations–for the sun’s curious recent lull remained opaque. “I think we’re almost in violent agreement that this is an interesting minimum,” said David Hathaway of the NASA Marshall Space Flight Center in Huntsville, Ala.
[More]
NASA – Sun – Marshall Space Flight Center – Sunspot – American Astronomical Society
06/30/2010
10:00 PM
NASA’s Plan to Use Commercial Rockets Lifts Off
Private access to space took a giant leap forward on June 4 with a successful test launch of the Falcon 9 rocket, developed and built by SpaceX, a venture headed by PayPal co-founder Elon Musk.
The two-stage Falcon 9, which stands 48 meters tall, lifted off from Cape Canaveral carrying a dummy capsule that could soon deliver supplies to the International Space Station–and, one day, even astronauts to orbit.
[More]
Falcon 9 – International Space Station – NASA – Cape Canaveral – SpaceX
06/30/2010
03:04 PM
What can a three-legged dog teach robots about resilience?
Anyone who’s ever seen a dog move around on three limbs knows that canines are remarkably resilient creatures. Scientists are now wondering whether such adaptability could likewise be programmed into robots, in the event they experience damage or malfunction far from a repair shop (look no further than NASA’s Mars Spirit rover to see why this is important). [More]
NASA – Mars – Spirit rover – Space – Dog
06/30/2010
08:00 AM
Some Milky Way Stars Are Survivors of Older Galaxies
It’s a plotline worthy of an action film–galaxies, violently torn apart, smashing into one another, leaving remnants of themselves behind billions of years later. That’s the scene that accounts for some of the oldest stars in our own Milky Way galaxy, according to work published in the journal Monthly Notices of the Royal Astronomical Society. [Andrew Cooper et al., http://bit.ly/9hMtBZ ]
Researchers ran a huge computer simulation of the evolution of the universe starting shortly after the big bang, more than 13 billion years ago. It’s the most detailed model ever produced, and allowed a close examination of the make-up of the Milky Way’s stellar halo. The stellar halo is debris that surrounds our familiar white swirl of stars. The halo is much larger and much older than the Milky Way itself.
[More]
Milky Way – Astronomy – Galaxies – Star – Big Bang
06/29/2010
03:59 PM
How did life begin on Earth?
LINDAU, Germany–What steps led to the origin of life on Earth? Scientists may be zeroing in on that most profound of questions. “We’ve gone a long way to showing” the processes that “set the stage” for cellular life on Earth, Jack Szostak said Tuesday here in his talk at the 60th annual Nobel Laureate Lectures at Lindau .
Recent findings–such as that life seems to be everywhere on Earth–have encouraged scientific inquiries into the nature of life’s beginnings, said Szostak. Along with Elizabeth H. Blackburn and Carol W. Greider, Szostak won the 2009 Nobel Prize in Physiology or Medicine for work in understanding telomeres [see Blackburn and Greider's Scientific American article “ Telomeres, Telomerase and Cancer ”]. His talk focused on his recent research on life’s start [see his Scientific American 2009 article, “ The Origin of Life on Earth ”]. He cited discoveries of microbes eking out existence in steaming hot springs in Yellowstone, in an acidic environment in Rio Tinto, Spain, and other hostile locations. “Even in rocks, there’s life,” he added, showing the audience an image of a green streak tenaciously spreading through rock. “Once life gets started, it can adapt and colonize many, many different environments.” In addition, astronomers have found hundreds of planets in other solar systems , and the space-based Kepler telescope recently identified more than 700 more candidate exoplanets. Many of those could have Earth-like conditions, raising the possibility that they also could harbor some form of life. How common might life be? “The question is: Is it easy or hard to make the transition in the chemistry of planets from not alive to alive?” asked Szostak.
[More]
Lindau – Abiogenesis – Earth – List of Nobel laureates – Jack W. Szostak
06/23/2010
02:31 PM
Once more into the breach for Orbital Sciences and the carbon observatory
The Orbiting Carbon Observatory was meant to precisely measure carbon dioxide throughout Earth’s atmosphere. Instead, it wound up shattering on the Pacific Ocean* near Antarctica in 2009, a victim of a failed fairing–the aerodynamic nose cone shroud that keeps the satellite from burning up during launch. [More]
Orbiting Carbon Observatory – Atlantic Ocean – Earth – Orbital Sciences Corporation – Antarctica
06/23/2010
12:58 PM
NASA may delay final space shuttle launch until 2011
The final planned space shuttle mission, currently slated for mid-November at the earliest, may not lift off until February 2011, according to a NASA spokesperson. [More]
Space Shuttle – NASA – Space – Technology – Missions
06/23/2010
12:30 PM
Extra-Stormy Weather: Exoplanet Atmosphere Roils with Superspeed Winds
A long-studied planet orbiting a star 150 light-years away has been given a new look, thanks to a novel method of studying extrasolar planets from Earth. [More]
Extrasolar planet – Earth – Astronomy – Light-year – Solar System
06/23/2010
11:19 AM
Neutrino Mass Upper Limit Estimated by Galactic Distribution
“Six thousand billion of them are going through your body every second.” That’s physicist Lawrence Krauss on neutrinos, on the June 15th weekly Science Talk podcast. “Neutrinos are the lightest elementary particles we know of. The name comes from the fact that they had to be neutral because we couldn’t see them in detectors. But they had to be light. So Enrico Fermi called them "a little neutron," in Italian is neutrino. So they were baby neutrons, which were the only other neutral particles at the time that were known.”
Now astrophysicists [Shaun Thomas, Ofer Lahav and Filipe Abdalla] have put a best-guess upper limit on the mass of the neutrino. The research is being reported this week at the Weizmann U.K. conference at University College London and will appear in an upcoming issue of Physical Review Letters .
[More]
Neutrino – University College London – Physics – Enrico Fermi – Elementary particle
06/22/2010
01:20 PM
Space Rock Watch: Next Generation of Near-Earth Asteroid Lookout Comes Online
A new sentry is on guard atop the Haleakala volcano in Hawaii, scanning the skies for potentially threatening asteroids and comets. The first of four telescopes planned for the Pan-STARRS project, short for Panoramic Survey Telescope and Rapid Response System, began a dedicated survey of the sky May 13. [More]
Pan-STARRS – Near-Earth object – Hawaii – Asteroid – Telescope
06/21/2010
12:50 PM
Data Deluge: Texas Flood Canyon Offers Test of Hydrology Theories for Earth and Mars
A geologic scar left by a catastrophic Texas flood in 2002 is providing an unexpected scientific benefit. A new study demonstrates how researchers can use a channel carved by floodwaters pouring over the dam of a flooded reservoir as a laboratory to test scientific theories of how such canyons are formed. The research could help to inform the hydrological histories of Earth and Mars by indicating the kind of imprints large, sudden floods leave on a planet’s surface. [More]
Flood – Mars – Dam – Earth – Earth Sciences
06/21/2010
09:30 AM
Is the Universe Leaking Energy? (preview)
Energy can neither be created nor destroyed. This principle, called conservation of energy, is one of our most cherished laws of physics. It governs every part of our lives: the heat it takes to warm up a cup of coffee; the chemical reactions that produce oxygen in the leaves of trees; the orbit of Earth around the sun; the food we need to keep our hearts beating. We cannot live without eating, cars do not run without fuel, and perpetual-motion machines are just a mirage. So when an experiment seems to violate the law of energy conservation, we are rightfully suspicious. What happens when our observations seem to contradict one of science’s most deeply held notions: that energy is always conserved?
Skip for a moment outside our Earthly sphere and consider the wider universe. Almost all of our information about outer space comes in the form of light, and one of light’s key features is that it gets redshifted–its electromagnetic waves get stretched–as it travels from distant galaxies through our ever expanding universe, in accordance with Albert Einstein’s general theory of relativity. But the longer the wavelength, the lower the energy. Thus, inquisitive minds ask: When light is redshifted by the expansion of the universe, where does its energy go? Is it lost, in violation of the conservation principle?
[More]
Albert Einstein – Energy conservation – General relativity – Metric expansion of space – Physics