Archive

Archive for May, 2012

Electric Moon Jolts The Solar Wind


With the moon as the most prominent object in the night sky and a major source of an invisible pull that creates ocean tides, many ancient cultures thought it could also affect our health or state of mind – the word “lunacy” has its origin in this belief. Now, a powerful combination of spacecraft and computer simulations is revealing that the moon does indeed have a far-reaching, invisible influence – not on us, but on the Sun, or more specifically, the solar wind.

Unlike Earth, the moon is not surrounded by a global magnetic field. “It was thought that the solar wind crashes into the lunar surface without any warning or ‘push back’ on the solar wind,” says Dr. Andrew Poppe of the University of California, Berkeley. Recently, however, an international fleet of lunar-orbiting spacecraft has detected signs of the moon’s presence “upstream” in the solar wind. “We’ve seen electron beams and ion fountains over the moon’s day side,” says Dr. Jasper Halekas, also of the University of California, Berkeley.

Full Story: http://www.nasa.gov/topics/solarsystem/features/electric-moon.html

Advertisements

Astronomers And Students From Williams College To Study The Transit Of Venus


WILLIAMSTOWN, Mass., May 30, 2012 – The June 5 transit of the planet Venus across the face of our Sun, a rare event that won’t recur until 2117, is the subject of detailed study by a team of faculty and students from Williams College and their collaborators around the country and the world. They will be observing the event from the 10,000 foot location of the University of Hawaii’s Mees Solar Observatory on Haleakala, a dormant volcano on Maui, in a Science Park of telescopes there that is soon to contain the Advanced Technology Solar Telescope. Their work is sponsored by a research grant from the Committee for Research and Exploration of the National Geographic Society.

Full Story: http://communications.williams.edu/news/5_30_2012_pasachoff_venus/

Stellar Archaeology Traces Milky Way’s History


Unfortunately, stars don’t have birth certificates. So, astronomers have a tough time figuring out their ages. Knowing a star’s age is critical for understanding how our Milky Way galaxy built itself up over billions of years from smaller galaxies.

Jason Kalirai of the Space Telescope Science Institute and The Johns Hopkins University’s Center for Astrophysical Sciences, both in Baltimore, Md., has found the next best thing to a star’s birth certificate. Using a new technique, Kalirai probed the burned-out relics of Sun-like stars, called white dwarfs, in the inner region of our Milky Way galaxy’s halo. The halo is a spherical cloud of stars surrounding our galaxy’s disk.

Those stars, his study reveals, are 11.5 billion years old, younger than the first generation of Milky Way stars. They formed more than 2 billion years after the birth of the universe 13.7 billion years ago. Previous age estimates, based on analyzing normal stars in the inner halo, ranged from 10 billion to 14 billion years.

Full Story: http://hubblesite.org/newscenter/archive/releases/2012/25/

NASA Preparing To Launch Its Newest X-Ray Eyes


PASADENA, Calif. — NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, is being prepared for the final journey to its launch pad on Kwajalein Atoll in the central Pacific Ocean. The mission will study everything from massive black holes to our own sun. It is scheduled to launch no earlier than June 13.

“We will see the hottest, densest and most energetic objects with a fundamentally new, high-energy X-ray telescope that can obtain much deeper and crisper images than before,” said Fiona Harrison, the NuSTAR principal investigator at the California Institute of Technology in Pasadena, Calif., who first conceived of the mission 20 years ago.

Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2012-147

Mars Missions May Learn From Meteor


Scientists have tried to find out how the planet’s environment came to contain methane gas, which contains carbon – a substance found in all living things.

They found that meteorites, which continually bombard the surface of Mars, contain enough carbon compounds to generate methane when they are exposed to sunlight.

Scientists planning future missions to Mars could use the findings to fine-tune their experiments, potentially making their trips more valuable.

Full Story: http://www.ed.ac.uk/news/all-news/300512-mars

ALMA Turns Its Eyes To Centaurus A


Centaurus A is a massive elliptical radio galaxy — a galaxy which emits strong radio waves — and is the most prominent, as well as by far the nearest, radio galaxy in the sky. Centaurus A has therefore been observed with many different telescopes. Its very luminous centre hosts a supermassive black hole with a mass of about 100 million times that of the Sun.

In visible light, a characteristic feature of the galaxy is the dark band that obscures its centre . This dust lane harbours large amounts of gas, dust and young stars. These features, together with the strong radio emission, are evidence that Centaurus A is the result of a collision between a giant elliptical galaxy, and a smaller spiral galaxy whose remains form the dusty band.

To see through the obscuring dust in the central band, astronomers need to observe using longer wavelengths of light. This new image of Centaurus A combines observations at wavelengths around one millimetre, made with ALMA, and observations in near-infrared light. It thus provides a clear view through the dust towards the galaxy’s luminous centre.

Full Story:http://www.eso.org/public/news/eso1222/

There’s More Star-Stuff Out There But It’s Not Dark Matter


More atomic hydrogen gas — the ultimate fuel for stars — is lurking in today’s Universe than we thought, CSIRO astronomer Dr Robert Braun has found.

This is the first accurate measurement of this gas in galaxies close to our own.

By taking a new look at some archival data, Dr Braun, Chief Scientist at CSIRO Astronomy and Space Science in Sydney, Australia, has discovered that galaxies around us are hiding about a third more atomic hydrogen gas than previously calculated.

Full Story: http://www.csiro.au/en/Portals/Media/Atomic-hydrogen-gas.aspx