In the Stars: Nature's atom-smasher

WASHINGTON, April 11 (UPI) -- In the world of astronomy, science fiction sometimes predicts science fact. Concepts and devices thought to be extreme or impossible can make surprising appearances in the world of reality.

When Sir Arthur C. Clarke wrote "2010," the sequel to his classic short story, "The Sentinel" -- which became much more famous as the 1968 film, "2001: A Space Odyssey" -- he mentioned the possibility of giant diamonds embedded in the cores of planets.

Recently, scientists at Princeton University analyzed the composition of meteorites and certain stars and concluded some planets might be so carbon-rich that part of their interiors have turned into diamond layers hundreds of miles thick.

In Carl Sagan's novel, "Contact," an alien from an advanced civilization discloses an engineering project on a galactic scale -- actually using black holes to power an interstellar rapid-transit system.

The terminus of the colossal system was none other than Sagittarius A, the super-massive black hole at the center of the Milky Way.

It is merely a coincidence, but British and German astronomers have just found a vast loop-like structure -- perhaps 20 light-years across -- that seems to be acting like a gigantic particle accelerator.

Using the European X-ray satellite, the team found the loop in the Arches stellar cluster, adjacent to the most massive star-forming region in the galaxy, itself very close to the area of the sky occupied by Sagittarius -- the Archer.

"The X-ray spectrum of the loop is extraordinary," said Masaaki Sakano, at the University of Leicester. "Most diffuse X-ray sources in the universe have a characteristic temperature because they are the residual radiation from an event, such as a supernova explosion. However, in this case the loop is non-thermal and this means that whatever the origin of the structure is, it is not stationary but rather the result of some ongoing process."

In other words, there does not seem to be an obvious source generating the tremendous power needed to operate this thing.

Certain phenomena in the universe produce awesome levels of energy -- supernovae and gamma-ray bursts, to name just two -- but those events are destructive and site specific. They wipe out anything in their paths across great distances -- in the case of gamma-ray bursts, across thousands of light-years -- but they are caused by a single exploding star.

Pulsars -- the burned out, super-dense remains of stars that have exploded -- represent another source of high-energy particles. Again, these objects, which also tend to wreak havoc in their neighborhoods by pouring out huge amounts of deadly radiation, represent specific causes.

Not the Arches loop. So far, Masaaki and colleagues have not been able to isolate the power generator that is creating the particles, whose energy is equivalent to a thousand trillion electron volts. Pound for pound, that is about 1,000 times more powerful than the biggest particle accelerators on Earth, whose activities last for only brief periods and which are infinitesimally smaller.

As with anything going on near the galactic center, the Arches cluster had to be observed in X-ray wavelengths of light because so much dust lies near the Milky Way's heart that it blocks the view of optical telescopes.

The team said they also have not been able to determine whether the loop is actually located near the Arches star cluster or just happens to be in the same line of sight. They need to conduct further observations to be sure.

If they find that Arches somehow is responsible for the phenomenon, it will suggest star-forming plays a role in the creation of cosmic rays, something entirely new in particle physics.

Or, it might, possibly, represent the slightest hint an advanced civilization is conducting atom-smashing experiments on an interstellar scale, for the whole galaxy to notice.

--

In the Stars is a series by UPI examining new discoveries about the cosmos. E-mail: sciencemail@upi.com