Stellary Starry Universe

NASA's Voyager probes have reached the edge of the solar system and found something surprising there–a froth of magnetic bubbles separating us from the rest of the galaxy.

To commemorate an unprecedented tripling of flybys, orbital insertions and launches to planets, comets and asteroids, NASA has declared the year ahead "The Year of the Solar System."

 

Giant planet GJ 436b in the constellation Leo is missing something–and that something is swamp gas. To the surprise of astronomers who have been studying the Neptune-sized planet using NASA’s Spitzer Space Telescope, GJ 436b has very little methane–an ingredient common to many planets in our own solar system.

This artist’s concept shows the unusual, methane-free world partially eclipsed by its star. Models of planetary atmospheres indicate that any world with the common mix of hydrogen, carbon and oxygen, and a temperature up to 1,000 Kelvin (1,340 degrees Fahrenheit) should have a large amount of methane and a small amount of carbon monoxide. But at about 800 Kelvin (or 980 degrees Fahrenheit), GJ 436b it does not. The finding demonstrates the diversity of exoplanets and the need for further study. Image Credit: NASA/JPL-Caltech

 

NASA’s IBEX spacecraft has discovered a vast, glowing ribbon at the edge of the solar system. One mission scientist calls the discovery "shocking" and says theorists are "working like crazy" to explain the finding.

October 15, 2009: For years, researchers have known that the solar system is surrounded by a vast bubble of magnetism. Called the “heliosphere,” it springs from the sun and extends far beyond the orbit of Pluto, providing a first line of defense against cosmic rays and interstellar clouds that try to enter our local space. Although the heliosphere is huge and literally fills the sky, it emits no light and no one has actually seen it.

Until now.

NASA’s IBEX (Interstellar Boundary Explorer) spacecraft has made the first all-sky maps of the heliosphere and the results have taken researchers by surprise. [...]

 

 

Source: Nasa Science – click here for full article

 

SYDNEY: New evidence backs up the idea that a shockwave from the explosion of massive star triggered the collapse of a dense, dusty gas cloud to form our Sun and its retinue of planets.

For many decades astronomers have postulated that the after effects of this violent supernova led to the birth of the Solar System.

But detailed models of this formation process have only produced the right results under the simplifying – and likely wrong – assumption that the temperatures during the violent events remained constant.

Devil in the details

Now, U.S. astrophysicists at the Carnegie Institution, in Washington DC, have shown for the first time that a supernova could indeed have triggered the Solar System’s formation under the more likely conditions of rapid heating and cooling.

They argue that their results, published last month in the Astrophysical Journal, resolve a long-standing debate.

“We’ve had chemical evidence from meteorites that points to a supernova triggering our Solar System’s formation since the 1970s,” said Alan Boss, lead author of the study.

“But the devil has been in the details,” he said. “Until this study, scientists have not been able to work out a self-consistent scenario, where collapse is triggered at the same time that newly created isotopes from the supernova are injected into the collapsing cloud.”

Short-lived radioactive isotopes – versions of elements with the same number of protons, but a different number of neutrons – found in very old meteorites decay on time scales of millions of years and turn into different ‘daughter’ elements.

Source: Cosmos Online – click here or title for full article