Interstellar Boundary Explorer (IBEX) has captured the best and most complete glimpse yet of what lies beyond the solar system. The new measurements give clues about how and where our solar system formed, the forces that physically shape our solar system, and the history of other stars in the Milky Way.

The Earth-orbiting spacecraft observed four separate types of atoms including hydrogen, oxygen, neon and helium. These interstellar atoms are the byproducts of older stars, which spread across the galaxy and fill the vast space between stars. IBEX determined the distribution of these elements outside the solar system, which are flowing charged and neutral particles that blow through the galaxy, or the so-called interstellar wind.

“IBEX is a small Explorer mission and was built with a modest investment,” said Barbara Giles, director of the Heliophysics Division at NASA Headquarters in Washington. “The science achievements though have been truly remarkable and are a testament to what can be accomplished when we give our nation’s scientists the freedom to innovate.”

In a series of science papers appearing in the Astrophysics Journal on Jan. 31, scientists report finding 74 oxygen atoms for every 20 neon atoms in the interstellar wind. In our own solar system, there are 111 oxygen atoms for every 20 neon atoms. This translates to more oxygen in any part of the solar system than in nearby interstellar space.

“Our solar system is different than the space right outside it, suggesting two possibilities,” says David McComas, IBEX principal investigator, at the Southwest Research Institute in San Antonio. “Either the solar system evolved in a separate, more oxygen-rich part of the galaxy than where we currently reside, or a great deal of critical, life-giving oxygen lies trapped in interstellar dust grains or ices, unable to move freely throughout space.”

The new results hold clues about the history of material in the universe. While the big bang initially created hydrogen and helium, only the supernovae explosions at the end of a star’s life can spread the heavier elements of oxygen and neon through the galaxy. Knowing the amounts of elements in space may help scientists map how our galaxy evolved and changed over time.

Scientists want to understand the composition of the boundary region that separates the nearest reaches of our galaxy, called the local interstellar medium, from our heliosphere. The heliosphere acts as a protective bubble that shields our solar system from most of the dangerous galactic cosmic radiation that otherwise would enter the solar system from interstellar space.

IBEX measured the interstellar wind traveling at a slower speed than previously measured by the Ulysses spacecraft, and from a different direction. The improved measurements from IBEX show a 20 percent difference in how much pressure the interstellar wind exerts on our heliosphere.

“Measuring the pressure on our heliosphere from the material in the galaxy and from the magnetic fields out there will help determine the size and shape of our solar system as it travels through the galaxy,” says Eric Christian, IBEX mission scientist, at NASA’s Goddard Space Flight Center in Greenbelt, Md.

The IBEX spacecraft was launched in October 2008. Its science objective is to discover the nature of the interactions between the solar wind and the interstellar medium at the edge of our solar system.

The Southwest Research Institute developed and leads the IBEX mission with a team of national and international partners. The spacecraft is one of NASA’s series of low-cost, rapidly developed missions in the Small Explorers Program. Goddard manages the program for the agency’s Science Mission Directorate at NASA Headquarters in Washington.

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In early December, an international team of astronomers discovered an incredibly fast rotating star, rotating at a radial velocity of 1.6 million km/h (1 million mph), which is approximately 100 times faster than the sun rotates (roughly four times a day). If the star, dubbed VFTS (short for VLT-FLAMES Tarantula Survey) 102, spun any faster, the centrifugal forces would rip it apart.

Working at the European Southern Observatory’s Very Large Telescope at the Paranel Observatory in Chile, the team located VFTS 102 160,000 light-years away from the Earth in the Tarantula Nebula, which is part of the Large Magellanic Cloud, a satellite galaxy of our Milky Way galaxy. They detected the star because its traveling velocity was 30 km/s (70,000 mph) – much faster than those of other stars in the vicinity.

Philip Dufton, lead author of the paper that presents the team’s findings, stated, “The remarkable rotation speed and the unusual motion compared to the surrounding stars led us to wonder if this star had an unusual early life.” Dufton works at the Department of Physics and Astronomy at Queen’s University Belfast, Northern Ireland. “It was suspicious.”

The centrifugal forces of VFTS 102 (which is a blue giant and has twenty-five times the mass and 100,000 times the luminosity of the sun) are so great that the star has an oblate spheroid shape. Furthermore, they cause VFTS 102 to spin out a disk of plasma at its equator.

The team of astronomers speculate that VFTS 102 had a violent past. It may have been part of a binary star system in which it and its companion star closely rotated around each other. VFTS 102′s fast rotation may have come from the two stars being so close together, which could have caused the companion star to stream gas over to VFTS 102.

Another member of the team, Matteo Cantiello, an astrophysicist at the University of California, Santa Barbara, further explains in the university’s press release, “This gas falls onto the companion star, increasing the mass and spinning it up. Similar to a tennis ball spinning fast after being hit by a glancing blow, a star rotates quickly after being hit off-center by the in-falling gas.”

At some point, the companion star went supernova, expelling much of its gas. The intense explosion ejected VFTS 102, which was sent hurdling through space at the current velocity in which it was discovered. Presently, a supernova remnant and pulsar lie near the blue giant. That these two objects are located nearby VFTS 102 serves as evidence that supports the team’s hypothesis, as the supernova remnant and pulsar may belong to the late companion star, which may have collapsed into a neutron star following its exploding.

“This is a compelling story because it explains each of the unusual features that we’ve seen,” Dufton writes. “This star is certainly showing us unexpected sides of the short, but dramatic lives of the heaviest stars.”

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A pair of two-billion-year-old clouds of gas are providing scientists with new clues about the origins of the universe this week. These recently discovered pockets of “pristine gas” have remained untouched since the time of the Big Bang, and have never been mingled with heavier elements forged by later stars — giving them the lowest measurement of “metallacity” in the universe.

The discovery will help to lend further credence to the Big Bang theory, as researchers have long believed that only the lightest elements in the universe formed immediately after it’s creation. The lack of dense metals in the pristine clouds, which formed just minutes after the initial Big Bang, serves as some of the first hard evidence of the theory’s accuracy.

In an interview with SPACE.com, astronomer Michele Fumagalli of UC Santa Cruz commented;

“It’s actually a very nice confirmation of the theory, because the theory predicts that in the first few minutes after the Big Bang, things like hydrogen and helium were produced and no metals. So, this is the first time that we have a very strong observation and evidence that indeed this theory is correct. It’s good news for cosmology.”

Distant objects in space are able to analyzed from Earth by rays of light that provide a “fingerprint” of the gases they contain, which is how it was discerned that these particular clouds contain only hydrogen and deuterium. The fact that such pockets of the universe exist uncontaminated by heavier elements is sufficient cause to reexamine the way stars disperse metals.

Originally, it was assumed that pristine gas was not locatable by scientists because heavy elements from early stars had been very thoroughly spread throughout the universe. Now that the clouds’ existence has been proven, researchers will be forced reconsider certain aspects of how matter travels through space.

Previous efforts have been made by scientists to find pristine gas, but this is the first successful attempt. An ongoing study of extragalactic gases revealed the clouds by chance near the constellations of Leo and Ursa Major. It is currently unknown how many other examples of pristine gas might exist throughout the universe, but the search is on for cosmologists.

Physicist John O’Meara of Saint Michael’s college was quoted by Discovery News explaining, ”One of our biggest questions in cosmology is how galaxies get the gas they need to form stars, and how they also sent out the remnants of stars into their surroundings.” Some researchers now theorize that pristine clouds may in fact be the source that feeds young galaxies the cold gas to create stars.

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