Featured Posts
Astro Watch
31 Jul 2014, 20:01 UTC
Earth and Mercury are both rocky planets with iron cores, but Mercury's interior differs from Earth's in a way that explains why the planet has such a bizarre magnetic field, University of California, Los Angeles (UCLA) planetary physicists and colleagues report. Measurements from NASA's Messenger spacecraft have revealed that Mercury's magnetic field is approximately three times stronger at its northern hemisphere than its southern one. In the current research, scientists led by Hao Cao, a UCLA postdoctoral scholar working in the laboratory of Christopher T. Russell, created a model to show how the dynamics of Mercury's core contribute to this unusual phenomenon. The magnetic fields that surround and shield many planets from the sun's energy-charged particles differ widely in strength. While Earth's is powerful, Jupiter's is more than 12 times stronger, and Mercury has a rather weak magnetic field. Venus likely has none at all. The magnetic fields of Earth, Jupiter and Saturn show very little difference between the planets' two hemispheres.Within Earth's core, iron turns from a liquid to a solid at the inner boundary of the planet's liquid outer core; this results in a solid inner part and liquid outer part. The solid inner core is growing, and ...
Mercury's Magnetic Field Tells Scientists How Its Interior Is Different from Earth's
31 Jul 2014, 20:01 UTC
Earth and Mercury are both rocky planets with iron cores, but Mercury's interior differs from Earth's in a way that explains why the planet has such a bizarre magnetic field, University of California, Los Angeles (UCLA) planetary physicists and colleagues report. Measurements from NASA's Messenger spacecraft have revealed that Mercury's magnetic field is approximately three times stronger at its northern hemisphere than its southern one. In the current research, scientists led by Hao Cao, a UCLA postdoctoral scholar working in the laboratory of Christopher T. Russell, created a model to show how the dynamics of Mercury's core contribute to this unusual phenomenon. The magnetic fields that surround and shield many planets from the sun's energy-charged particles differ widely in strength. While Earth's is powerful, Jupiter's is more than 12 times stronger, and Mercury has a rather weak magnetic field. Venus likely has none at all. The magnetic fields of Earth, Jupiter and Saturn show very little difference between the planets' two hemispheres.Within Earth's core, iron turns from a liquid to a solid at the inner boundary of the planet's liquid outer core; this results in a solid inner part and liquid outer part. The solid inner core is growing, and ...
SPACE.com
31 Jul 2014, 18:58 UTC
NASA's next big Mars rover launching in 2020 will be packed to the brim with high-tech instruments, including twin lasers, a water-hunting radar and a new drill to collect samples of Mars. See the seven science instruments on NASA's Mars rover 2020.
NASA's Next Mars Rover to Collect Martian Samples, Carry Lasers
31 Jul 2014, 18:58 UTC
NASA's next big Mars rover launching in 2020 will be packed to the brim with high-tech instruments, including twin lasers, a water-hunting radar and a new drill to collect samples of Mars. See the seven science instruments on NASA's Mars rover 2020.
io9 Space
31 Jul 2014, 18:30 UTC
We've heard about lots of big plans for the Moon: mining colonies, space tourism, science outposts, observatories, even art installations . But now we might be able to add "fossil park." New research suggests that fossils dislodged from Earth could have hit the lunar surface — and remained intact.Read more...
Could There Really Be Fossils From Earth On The Moon?
31 Jul 2014, 18:30 UTC
We've heard about lots of big plans for the Moon: mining colonies, space tourism, science outposts, observatories, even art installations . But now we might be able to add "fossil park." New research suggests that fossils dislodged from Earth could have hit the lunar surface — and remained intact.Read more...
Sky and Telescope
31 Jul 2014, 18:05 UTC
Astronomers have detected gamma-ray emission from three classical novae, an unexpected discovery that has left them perplexed.Some days, it seems like everything is dumped on you. As the pressure builds, you finally hit a point at which you just lose it and explode.In a classical nova, a white dwarf siphons material off a companion star, piling up material on its surface until thermonuclear processes kick off, creating a brilliant outburst.NASA / JPL-CaltechWhite dwarfs can have the same problem. When one of these stellar corpses funnels gas off a companion star, the white dwarf builds up a layer of material on its own surface until the temperature and pressure are so high that they trigger a thermonuclear explosion. The bright outburst, called a nova, can blaze for months. And unlike their brighter cousins the supernovae, novae don’t destroy the star and can actually repeat.Observations with NASA’s Fermi Gamma-ray Space Telescope now show that nova-ing white dwarfs throw a surprisingly energetic fit when they’ve had enough. Fermi observations of three “classical” novae — V959 Monocerotis 2012, V1324 Scorpii 2012, and V339 Delphini 2013 — reveal that these eruptions produce gamma rays, heretofore unexpected from this type of system.Each of the three novae ...
Novae Surprise with Gamma Rays
31 Jul 2014, 18:05 UTC
Astronomers have detected gamma-ray emission from three classical novae, an unexpected discovery that has left them perplexed.Some days, it seems like everything is dumped on you. As the pressure builds, you finally hit a point at which you just lose it and explode.In a classical nova, a white dwarf siphons material off a companion star, piling up material on its surface until thermonuclear processes kick off, creating a brilliant outburst.NASA / JPL-CaltechWhite dwarfs can have the same problem. When one of these stellar corpses funnels gas off a companion star, the white dwarf builds up a layer of material on its own surface until the temperature and pressure are so high that they trigger a thermonuclear explosion. The bright outburst, called a nova, can blaze for months. And unlike their brighter cousins the supernovae, novae don’t destroy the star and can actually repeat.Observations with NASA’s Fermi Gamma-ray Space Telescope now show that nova-ing white dwarfs throw a surprisingly energetic fit when they’ve had enough. Fermi observations of three “classical” novae — V959 Monocerotis 2012, V1324 Scorpii 2012, and V339 Delphini 2013 — reveal that these eruptions produce gamma rays, heretofore unexpected from this type of system.Each of the three novae ...
Bad Astronomy
31 Jul 2014, 16:53 UTC
On July 31, 1964 — 50 years ago today — the Ranger 7 probe snapped the very first picture of the Moon ever taken by a US spacecraft. Here's what it saw: Ranger 7 was the first of many to follow. It was designed to do two things: impact the Moon, and take pictures along the way. It worked beautifully. That picture above was taken at 13:08:45 UTC, when it was just over 2000 km from the surface. It took thousands of pictures before impacting minutes later (I've always loved the final image it took). I have to say, thinking about this gave me chills. We've been exploring other worlds via spacecraft for (just barely) longer than I've been alive. Since that time, over 50 additional spacecraft have achieved orbit around another celestial body (not including those orbiting the Sun). Many more have performed flybys; every big planet in the solar system has been visited, and we have a probe flying past Pluto next year. A dozen humans have walked on another world, and more than 500 have been into space. I'm tempted to say we live in a time of miracles of wonders, but they're not miracles. They're the ...
50 Years Ago Today, Ranger 7 Took a Lunar Death-Dive
31 Jul 2014, 16:53 UTC
On July 31, 1964 — 50 years ago today — the Ranger 7 probe snapped the very first picture of the Moon ever taken by a US spacecraft. Here's what it saw: Ranger 7 was the first of many to follow. It was designed to do two things: impact the Moon, and take pictures along the way. It worked beautifully. That picture above was taken at 13:08:45 UTC, when it was just over 2000 km from the surface. It took thousands of pictures before impacting minutes later (I've always loved the final image it took). I have to say, thinking about this gave me chills. We've been exploring other worlds via spacecraft for (just barely) longer than I've been alive. Since that time, over 50 additional spacecraft have achieved orbit around another celestial body (not including those orbiting the Sun). Many more have performed flybys; every big planet in the solar system has been visited, and we have a probe flying past Pluto next year. A dozen humans have walked on another world, and more than 500 have been into space. I'm tempted to say we live in a time of miracles of wonders, but they're not miracles. They're the ...
Astro Watch
31 Jul 2014, 16:42 UTC
Although ESA’s GOCE satellite is no more, all of the measurements it gathered during its life skirting the fringes our atmosphere, including the very last as it drifted slowly back to Earth, have been drawn together to offer new opportunities for science. Carrying the first 3D gravity sensor in space, this state-of-the-art satellite measured Earth’s gravity with unprecedented accuracy. GOCE’s four years in orbit resulted in a series of four gravity models, each more accurate than the last. These models have been used to generate corresponding ‘geoids’ – the surface of a global ocean moulded by gravity alone.Shaped by differences in gravity, the geoid is a crucial reference for understanding ocean circulation, sea-level change and ice dynamics.From a mission that just keeps giving, a fifth model has now been produced. It incorporates data collected throughout the satellite’s 42-month operational life.The previous geoid, released in March 2013, was based on 27 months of measurements.The satellite was designed to orbit at an extremely low altitude of 255 km to gain the best possible gravity measurements. At the end of 2012, low fuel consumption allowed operators to extend its life and start to lower the satellite a further 31 km for even more ...
Lifetime of Gravity Measurements Heralds New Beginning
31 Jul 2014, 16:42 UTC
Although ESA’s GOCE satellite is no more, all of the measurements it gathered during its life skirting the fringes our atmosphere, including the very last as it drifted slowly back to Earth, have been drawn together to offer new opportunities for science. Carrying the first 3D gravity sensor in space, this state-of-the-art satellite measured Earth’s gravity with unprecedented accuracy. GOCE’s four years in orbit resulted in a series of four gravity models, each more accurate than the last. These models have been used to generate corresponding ‘geoids’ – the surface of a global ocean moulded by gravity alone.Shaped by differences in gravity, the geoid is a crucial reference for understanding ocean circulation, sea-level change and ice dynamics.From a mission that just keeps giving, a fifth model has now been produced. It incorporates data collected throughout the satellite’s 42-month operational life.The previous geoid, released in March 2013, was based on 27 months of measurements.The satellite was designed to orbit at an extremely low altitude of 255 km to gain the best possible gravity measurements. At the end of 2012, low fuel consumption allowed operators to extend its life and start to lower the satellite a further 31 km for even more ...
Astrobiology Magazine
31 Jul 2014, 16:00 UTC
An international team of researchers has devised a precise method for calculating the mass of galaxies.
Weighing the Milky Way
31 Jul 2014, 16:00 UTC
An international team of researchers has devised a precise method for calculating the mass of galaxies.
Science World Report
31 Jul 2014, 15:33 UTC
Astronomers have long known that young protostars eject supersonic jets of gas from their north and south poles. Now, though, researchers have detected more than ever before--all at the same time.
Supersonic Jets Ejected from Young Stars Spied with New Sky Survey
31 Jul 2014, 15:33 UTC
Astronomers have long known that young protostars eject supersonic jets of gas from their north and south poles. Now, though, researchers have detected more than ever before--all at the same time.
io9 Space
31 Jul 2014, 15:00 UTC
Animals in space just can't get a break. First, everything from kittens to snakes were sent on the vomit comet to confusedly tumble around in zero-gravity. Then, mice were recruited to live aboard the International Space Station . Now, Russia sent a harem of geckos to get lucky in orbit. Read more...
