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Posts Tagged ‘solar systems’

NASA’s Voyager 1 Explores Final Frontier Of Our ‘Solar Bubble’

July 2, 2013 1 comment

Artist's concept. Image Credit: NASA/JPL-Caltech

Artist’s concept. Image Credit: NASA/JPL-Caltech

Data from Voyager 1, now more than 11 billion miles (18 billion kilometers) from the sun, suggest the spacecraft is closer to becoming the first human-made object to reach interstellar space.

Scientists have seen two of the three signs of interstellar arrival they expected to see: charged particles disappearing as they zoom out along the solar magnetic field, and cosmic rays from far outside zooming in. Scientists have not yet seen the third sign, an abrupt change in the direction of the magnetic field, which would indicate the presence of the interstellar magnetic field.

“This strange, last region before interstellar space is coming into focus, thanks to Voyager 1, humankind’s most distant scout,” said Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. “If you looked at the cosmic ray and energetic particle data in isolation, you might think Voyager had reached interstellar space, but the team feels Voyager 1 has not yet gotten there because we are still within the domain of the sun’s magnetic field.”

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-209
Also: http://www.jhuapl.edu/newscenter/pressreleases/2013/130627.asp

Wide Binary Stars Can Wreak Havoc In Planetary Systems

January 9, 2013 Leave a comment

An international team of astrophysicists has shown that planetary systems with very distant binary stars are particularly susceptible to violent disruptions, more so than if the systems had two stellar companions with tighter orbits around each other.

The team, led by Northwestern University’s Nathan Kaib, conducted 3,000 computer simulations to study the effects of binary stellar companions (some with tight orbits around each other and others with wide or distant orbits) on the formation and evolution of planetary systems.

The researchers found that wide binary stars in planetary systems can lead to dramatic events over time. In one hypothetical system, the researchers added a wide binary companion to the Earth’s solar system. This triggered at least one of four giant planets (Jupiter, Saturn, Uranus and Neptune) to be ejected in almost half of the simulations.

Full Story: http://www.northwestern.edu/newscenter/stories/2013/01/wide-binary-stars-can-wreak-havoc-in-planetary-systems.html

Astronomers Discover And “Weigh” Infant Solar System

December 8, 2012 Leave a comment

Astronomers have found the youngest still-forming solar system yet seen, an infant star surrounded by a swirling disk of dust and gas more than 450 light-years from Earth in the constellation Taurus.

The star currently has about one-fifth the mass of the Sun, but, the scientists say, will likely pull in material from its surroundings to eventually match the Sun’s mass. The disk surrounding the young star contains at least enough mass to make seven Jupiters, the largest planet in our Solar System.

“This very young object has all the elements of a solar system in the making,” said John Tobin, of the National Radio Astronomy Observatory. Tobin and his colleagues used the Submillimeter Array and the Combined Array for Millimeter-wave Astronomy to study the object, called L1527 IRS, residing in a stellar nursery called the Taurus Cloud.

Full Story: http://www.nrao.edu/pr/2012/youngsystem/

Voyager Observes Magnetic Field Fluctuations In Heliosheath

October 29, 2012 Leave a comment

As they near the outer reaches of the solar system, for the past several years the two Voyager spacecraft have been sending back observations that challenge scientists’ views of the physics at the edge of the heliosphere, the bubble created by charged particles flowing outward from the Sun. A new study looks at magnetic field fluctuations and cosmic ray intensity observed by Voyager I.

In 2004, Voyager I crossed the termination shock, the region where the solar wind begins to slow as it interacts with the interstellar medium. Just outside the termination shock is the heliosheath, where the solar wind continues to slow, reaching a stagnation region where solar wind speed drops to zero. Burlaga and Ness studied the magnetic field observed by Voyager I during 2010, when the spacecraft was moving through this stagnation region. Their analysis shows that magnetic field fluctuations outside the termination shock were primarily compressive fluctuations in field strength along the direction of the motion of the planets around the Sun. The fluctuations were observed on time scales of several hours.

Full Story: http://www.agu.org/news/press/jhighlight_archives/2012/2012-10-29.shtml#one

Slow-Moving Rocks Improve Oodds That Life Crashed To Earth From Space

September 25, 2012 1 comment

Microorganisms that crashed to Earth embedded in the fragments of distant planets might have been the sprouts of life on this one, according to new research presented at the European Planetary Sciences Congress (EPSC) on 25 September.

The researchers report that under certain conditions there is a high probability that life came to Earth — or spread from Earth to other planets — during the Solar System’s infancy when Earth and its planetary neighbours orbiting other stars would have been close enough to each other to exchange lots of solid material.

The findings provide the strongest support yet for lithopanspermia, the hypothesis that basic life forms are distributed throughout the Universe via meteorite-like planetary fragments cast forth by disruptions such as volcanic eruptions and collisions with objects such as asteroids.

Full Story: http://www.europlanet-eu.org/outreach/index.php?option=com_content&task=view&id=382&Itemid=41

Slow-Moving Rocks Better Odds That Life Crashed To Earth From Space

September 25, 2012 Leave a comment

Microorganisms that crashed to Earth embedded in the fragments of distant planets might have been the sprouts of life on this one, according to new research from Princeton University, the University of Arizona and the Centro de Astrobiología (CAB) in Spain.

The researchers report in the journal Astrobiology that under certain conditions there is a high probability that life came to Earth — or spread from Earth to other planets — during the solar system’s infancy when Earth and its planetary neighbors orbiting other stars would have been close enough to each other to exchange lots of solid material.

The findings provide the strongest support yet for “lithopanspermia,” the idea that basic life forms are distributed throughout the universe via meteorite-like planetary fragments cast forth by disruptions such as volcanic eruptions and collisions with other matter. Eventually, another planetary system’s gravity traps these roaming rocks, which can result in a mingling that transfers any living cargo.

Full Story: http://www.princeton.edu/main/news/archive/S34/82/42M30/

Signs Changing Fast For Voyager At Solar System Edge


Image credit: NASA/JPL-Caltech

Two of three key signs of changes expected to occur at the boundary of interstellar space have changed faster than at any other time in the last seven years, according to new data from NASA’s Voyager 1 spacecraft.

For the last seven years, Voyager 1 has been exploring the outer layer of the bubble of charged particles the sun blows around itself. In one day, on July 28, data from Voyager 1’s cosmic ray instrument showed the level of high-energy cosmic rays originating from outside our solar system jumped by five percent. During the last half of that same day, the level of lower-energy particles originating from inside our solar system dropped by half. However, in three days, the levels had recovered to near their previous levels.

A third key sign is the direction of the magnetic field, and scientists are eagerly analyzing the data to see whether that has, indeed, changed direction. Scientists expect that all three of these signs will have changed when Voyager 1 has crossed into interstellar space. A preliminary analysis of the latest magnetic field data is expected to be available in the next month.

Full Story:

Going Out Of Business: Planet-Forming DISK TURNS Off Lights, Locks Doors …


That surprise you feel when your favorite store turns off its lights, locks up its doors, and suddenly, for no apparent reason, goes out of business? That’s just how astronomers felt recently when a dusty disk of rocky debris around a nearby star abruptly shut down and by all appearances went out of business.

The star — designated TYC 8241 2652 and a young analog of our Sun — only a few years ago displayed all of the characteristics of hosting a solar system in the making. Now, it has transformed completely: very little of the warm dusty material thought to originate from collisions of rocky planets is apparent – it’s a mystery that has astronomers baffled.

The lack of an existing model for what is going on around this star is forcing astronomers to rethink what happens within young solar systems in the making.

Full Story: http://www.gemini.edu/node/11836

NASA’s Kepler Announces 11 Planetary Systems Hosting 26 Planets

January 26, 2012 Leave a comment

Image credit: NASA Ames/Dan Fabrycky, University of California, Santa Cruz

Image credit: NASA Ames/Dan Fabrycky, University of California, Santa Cruz

NASA’s Kepler mission has discovered 11 new planetary systems hosting 26 confirmed planets. These discoveries nearly double the number of verified Kepler planets and triple the number of stars known to have more than one planet that transits, or passes in front of, its host star. Such systems will help astronomers better understand how planets form.

The planets orbit close to their host stars and range in size from 1.5 times the radius of Earth to larger than Jupiter. Fifteen of them are between Earth and Neptune in size, and further observations will be required to determine which are rocky like Earth and which have thick gaseous atmospheres like Neptune. The planets orbit their host star once every six to 143 days. All are closer to their host star than Venus is to our sun.

“Prior to the Kepler mission, we knew of perhaps 500 exoplanets across the whole sky,” said Doug Hudgins, Kepler program scientist at NASA Headquarters in Washington. “Now, in just two years staring at a patch of sky not much bigger than your fist, Kepler has discovered more than 60 planets and more than 2,300 planet candidates. This tells us that our galaxy is positively loaded with planets of all sizes and orbits.”

Full Story: http://www.nasa.gov/mission_pages/kepler/news/new-multi-systems.html