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Archive for September, 2012

Navigating The Seas Of Titan

September 28, 2012 Leave a comment

Humanity has landed a rover on Mars. Now, say scientists, it’s time to land a boat on Titan. This outlandish scenario could become reality, according to engineers presenting their proposals at the European Planetary Science Congress on 27 September.

Titan, Saturn’s largest moon, is one of the most Earth-like bodies in the Solar System. With a thick atmosphere, a diameter between that of Earth and the planet Mercury, and a network of seas, lakes and rivers, it is in many respects more like a planet than a moon like the Earth’s.

The new plans, called the Titan Lake In-situ Sampling Propelled Explorer, proposes a boat-probe, propelled by wheels, paddles or screws. The probe would land in the middle of Ligeia Mare (the biggest lake, near Titan’s north pole), then set sail for the coast, taking scientific measurements along the way. The mission would last around six months to a year.

Full Story: http://www.europlanet-eu.org/outreach/index.php?option=com_content&task=view&id=391&Itemid=41

Fireworks In The Early Universe

September 28, 2012 Leave a comment

Artist impression (ESA/NASA/RUG
/MarcelZinger)

Galaxies in the early universe grew fast by rapidly making new stars. Such prodigious star formation episodes, characterized by the intense radiation of the newborn stars, were often accompanied by fireworks in the form of energy bursts caused by the massive central black hole accretion in these galaxies. This discovery by a group of astronomers led by Peter Barthel of the Kapteyn Institute of the University of Groningen in the Netherlands is published today in the Astrophysical Journal Letters.

Until recently these distant active galaxies were only interesting in their own right as peculiar exotic objects. Little was known about the composition of their galaxies, or their relationship to the normal galaxy population. However, in 2009 ESA’s Herschel space telescope was launched. Herschel is considerably larger than NASA’s Hubble, and operates at far-infrared wavelengths. This enables Herschel to detect heat radiation generated by the processes involved in the formation of stars and planets at a small scale, and of complete galaxies at a large scale.

Full Story: http://www.rug.nl/corporate/nieuws/archief/archief2012/nieuwsberichten/126-barthel

Sharpest-Ever Ground-Based Images Of Pluto And Charon: Proves A Powerful Tool For Exoplanet Discoveries

September 28, 2012 Leave a comment

Credit: Gemini Observatory/NSF/NASA/AURA

Despite being infamously demoted from its status as a major planet, Pluto (and its largest companion Charon) recently posed as a surrogate extrasolar planetary system to help astronomers produce exceptionally high-resolution images with the Gemini North 8-meter telescope. Using a method called reconstructive speckle imaging, the researchers took the sharpest ground-based snapshots ever obtained of Pluto and Charon in visible light, which hint at the exoplanet verification power of a large state-of-the-art telescope when combined with speckle imaging techniques. The data also verified and refined previous orbital characteristics for Pluto and Charon while revealing the pair’s precise diameters.

“The Pluto-Charon result is of timely interest to those of us wanting to understand the orbital dynamics of this pair for the 2015 encounter by NASA’s New Horizons spacecraft,” said Steve Howell of the NASA Ames Research Center, who led the study. In addition, Howell notes that NASA’s Kepler mission, which has already proven a powerful exoplanet discovery tool, will benefit greatly from this technique.

Full Story: http://www.gemini.edu/node/11893

Asteroid’s Troughs Suggest Stunted Planet

September 28, 2012 1 comment

Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Enormous troughs that reach across the asteroid Vesta may actually be stretch marks that hint of a complexity beyond most asteroids. Scientists have been trying to determine the origin of these unusual troughs since their discovery just last year. Now, a new analysis supports the notion that the troughs are faults that formed when a fellow asteroid smacked into Vesta’s south pole. The research reinforces the claim that Vesta has a layered interior, a quality normally reserved for larger bodies, such as planets and large moons.

Asteroid surface deformities are typically straightforward cracks formed by crashes with other asteroids. Instead, an extensive system of troughs encircles Vesta, the second most massive asteroid in the solar system, about one-seventh as wide as the Moon. The biggest of those troughs, named Divalia Fossa, surpasses the size of the Grand Canyon by spanning 465 kilometers (289 miles) long, 22 km (13.6 mi) wide and 5 km (3 mi) deep.

Full Story:

Sagan Planet Walk, Now The World’s Largest Exhibition, Extends To Hawaii

September 28, 2012 Leave a comment

The three-quarter-mile model of the solar system, with tiny spheres scattered across Ithaca representing the planets, will soon be the world’s largest exhibition, as it extends to Hawaii with a station depicting the star nearest the sun.

In keeping with the exhibition’s 1-to-5-billion scale, this new station representing Alpha Centauri will be located at the ‛Imiloa Astronomy Center on the University of Hawaii’s Hilo campus. The expanded walk will measure 5,000 miles from end to end, handily eclipsing the previous record of 66 miles held by artwork in the subway tunnels of Stockholm, Sweden.

Full Story: http://www.news.cornell.edu/stories/Sept12/PlanetWalk.html

Dawn Suggests Special Delivery Of Hydrated Material To Vesta

September 27, 2012 Leave a comment

The mechanism by which water is incorporated into the terrestrial planets is a matter of extensive debate for planetary scientists. Now, observations of Vesta by NASA’s Dawn mission suggest that hydrous materials were delivered to the giant asteroid mainly through a build-up of small particles during an epoch when the Solar System was rich in dust. This is a radically different process from the way in which hydrous materials are deposited on the moon and may have implications for the formation of terrestrial planets, including the delivery of the water that forms Earth’s oceans.

Maria Cristina De Sanctis, of the Institute of Astrophysics and Space Planetology in Rome, said, ‘Vesta’s surface shows distinct areas enriched with hydrated materials. These regions are not dependent on solar illumination or temperature, as we find in the case of the Moon. The uneven distribution is unexpected and indicates ancient processes that differ from those believed to be responsible for delivering water to other airless bodies, like the Moon.’

Full Story: http://www.europlanet-eu.org/outreach/index.php?option=com_content&task=view&id=387&Itemid=1

Hubble Goes To The eXtreme To Assemble The Deepest Ever View Of The Universe

September 26, 2012 Leave a comment

Image Credit: NASA, ESA, G. Illingworth, D. Magee, and P. Oesch (University of California, Santa Cruz), R. Bouwens (Leiden University), and the HUDF09 Team

Like photographers assembling a portfolio of their best shots, astronomers have assembled a new, improved portrait of our deepest-ever view of the Universe. Called the eXtreme Deep Field, or XDF, the photo was assembled by combining ten years of NASA/ESA Hubble Space Telescope observations taken of a patch of sky within the original Hubble Ultra Deep Field. The XDF is a small fraction of the angular diameter of the full Moon.

The new full-colour XDF image is even more sensitive than the original Hubble Ultra Deep Field image, thanks to the additional observations, and contains about 5500 galaxies, even within its smaller field of view. The faintest galaxies are one ten-billionth the brightness that the unaided human eye can see.

Peppered across the field are tiny, faint, and yet more distant galaxies that are like the seedlings from which today’s magnificent galaxies grew. The history of galaxies — from soon after the first galaxies were born to the great galaxies of today, like the Milky Way — is laid out in this one remarkable image.

Full Story: http://www.spacetelescope.org/news/heic1214/
Also: http://hubblesite.org/newscenter/archive/releases/2012/37

Curiosity Finishes Close Inspection Of Rock Target

September 26, 2012 Leave a comment

This image shows the robotic arm of NASA’s Mars rover Curiosity with the first rock touched by an instrument on the arm. Image credit: NASA/JPL-Caltech

NASA’s rover Curiosity touched a Martian rock with its robotic arm for the first time on Sept. 22, assessing what chemical elements are in the rock called “Jake Matijevic.”

After a short drive the preceding day to get within arm’s reach of the football-size rock, Curiosity put its Alpha Particle X-Ray Spectrometer (APXS) instrument in contact with the rock during the rover’s 46th Martian day, or sol. The APXS is on a turret at the end of the rover’s 7-foot (2.1-meter) arm. The Mars Hand Lens Imager (MAHLI), on the same turret, was used for close-up inspection of the rock. Both instruments were also used on Jake Matijevic on Sol 47 (Sept. 23).

The Chemistry and Camera (ChemCam) instrument, which shoots laser pulses at a target from the top of Curiosity’s mast, also assessed what chemical elements are in the rock Jake Matijevic. Using both APXS and ChemCam on this rock provides a cross calibration of the two instruments.

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2012-300

The Rich Colours Of A Cosmic Seagull

September 26, 2012 Leave a comment

This new image from the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile shows the head part of the Seagull Nebula. It is just one part of the larger nebula known more formally as IC 2177, which spreads its wings with a span of over 100 light-years and resembles a seagull in flight. This cloud of gas and dust is located about 3700 light-years away from Earth. The entire bird shows up best in wide-field images.

The complex of gas and dust that forms the head of the seagull glows brightly in the sky due to the strong ultraviolet radiation coming mostly from one brilliant young star — HD 53367 — that can be spotted in the centre of the image and could be taken to be the seagull’s eye.

The radiation from the young stars causes the surrounding hydrogen gas to glow with a rich red colour and become an HII region. Light from the hot blue-white stars is also scattered off the tiny dust particles in the nebula to create a contrasting blue haze in some parts of the picture.

Full Story: http://www.eso.org/public/news/eso1237/

Where is Deimos?

September 25, 2012 Leave a comment

Mars Express image of the moons Phobos (foreground) and Deimos (background). Credit: ESA/DLR/FU Berlin (G. Neukum)

Despite more than a century of observations, the orbit of the Martian moon Deimos is still not known to a high degree of accuracy, but a new study using images taken by ESA’s Mars Express orbiter has provided the best orbital model to date.

135 years have passed since Asaph Hall discovered Phobos and Deimos, two small companions of the planet Mars. Since that time, the satellites have been imaged innumerable times from the Earth and from spacecraft, including recent measurements by the panoramic cameras on the Mars Exploration Rovers and instruments on the Mars Reconnaissance Orbiter.

Full Story: http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=50842