Washington, D.C. – Fire, it is often said, is mankind’s oldest chemistry experiment.
For thousands of years, people have been mixing the oxygen-rich air of Earth with an almost endless variety of fuels to produce hot luminous flame.
There’s an arc of learning about combustion that stretches from the earliest campfires of primitive humans to the most advanced automobiles racing down the superhighways of the 21st century.
Pasadena, CA – NuSTAR has been busy studying the most energetic phenomena in the universe. Recently, a few high-energy events have sprung up, akin to “things that go bump in the night.”
When one telescope catches a sudden outpouring of high-energy light in the sky, NuSTAR and a host of other telescopes stop what they were doing and take a better look.
For example, in early April, the blazar Markarian 421 had an episode of extreme activity, brightening by more than 50 times its typical level. Blazars are a special class of galaxies with accreting, or “feeding,” supermassive black holes at their centers.
Pasadena, CA – Ocean waters melting the undersides of Antarctic ice shelves are responsible for most of the continent’s ice shelf mass loss, a new study by NASA and university researchers has found.
Scientists have studied the rates of basal melt, or the melting of the ice shelves from underneath, of individual ice shelves, the floating extensions of glaciers that empty into the sea. But this is the first comprehensive survey of all Antarctic ice shelves. The study found basal melt accounted for 55 percent of all Antarctic ice shelf mass loss from 2003 to 2008, an amount much higher than previously thought.
Pasadena, CA – Researchers have discovered that temperatures in the Martian atmosphere regularly rise and fall not just once each day, but twice according to data from NASA’s Mars Reconnaissance Orbiter.
“We see a temperature maximum in the middle of the day, but we also see a temperature maximum a little after midnight,” said Armin Kleinboehl of NASA’s Jet Propulsion Laboratory in Pasadena, CA, who is the lead author of a new report on these findings.
Greenbelt, MD – A new study by astronomers at NASA, Johns Hopkins University and the Rochester Institute of Technology confirms long-held suspicions about how stellar-mass black holes produce their highest-energy light.
“Our work traces the complex motions, particle interactions and turbulent magnetic fields in billion-degree gas on the threshold of a black hole, one of the most extreme physical environments in the universe,” said lead researcher Jeremy Schnittman, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, MD.
Pasadena, CA – Newly formed stars shine brightly, practically crying out, “Hey, look at me!” But not everything in our Milky Way galaxy is easy to see. The bulk of material between the stars in the galaxy — the cool hydrogen gas from which stars spring — is nearly impossible to find.
A new study from the Herschel Space Observatory, a European Space Agency mission with important NASA participation, is shining a light on these hidden pools of gas, revealing their whereabouts and quantities. In the same way that dyes are used to visualize swirling motions of transparent fluids, the Herschel team has used a new tracer to map the invisible hydrogen gas.
Pasadena, CA – Nearly a decade ago, NASA’s Chandra X-ray Observatory caught signs of what appeared to be a black hole snacking on gas at the middle of the nearby Sculptor galaxy. Now, NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR), which sees higher-energy X-ray light, has taken a peek and found the black hole asleep.
“Our results imply that the black hole went dormant in the past 10 years,” said Bret Lehmer of the Johns Hopkins University, Baltimore, MD, and NASA’s Goddard Space Flight Center, Greenbelt, MD. “Periodic observations with both Chandra and NuSTAR should tell us unambiguously if the black hole wakes up again. If this happens in the next few years, we hope to be watching.” Lehmer is lead author of a new study detailing the findings in the Astrophysical Journal.
NASA’s Mars Reconnaissance Orbiter photos show Gullies on Martian Dunes that may have been created by Dry-Ice Sleds
Pasadena, CA – NASA research indicates hunks of frozen carbon dioxide — dry ice — may glide down some Martian sand dunes on cushions of gas similar to miniature hovercraft, plowing furrows as they go.
Researchers deduced this process could explain one enigmatic class of gullies seen on Martian sand dunes by examining images from NASA’s Mars Reconnaissance Orbiter (MRO) and performing experiments on sand dunes in Utah and California.
Pasadena, CA – Flying low and slow above the wild, pristine terrain of Alaska’s North Slope in a specially instrumented NASA plane, research scientist Charles Miller of NASA’s Jet Propulsion Laboratory, Pasadena, CA, surveys the endless whiteness of tundra and frozen permafrost below.
On the horizon, a long, dark line appears. The plane draws nearer, and the mysterious object reveals itself to be a massive herd of migrating caribou, stretching for miles. It’s a sight Miller won’t soon forget.
Pasadena, CA – Using an innovative satellite technique, NASA scientists have determined that a previously unmapped type of wildfire in the Amazon rainforest is responsible for destroying several times more forest than has been lost through deforestation in recent years.
In the southern Amazon rainforest, fires below the forest treetops, or “understory fires,” have been hidden from view from NASA satellites that detect actively burning fires. The new method has now led to the first regional estimate of understory fire damages across the southern Amazon.
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