ATLANTA - "These observations will challenge the theorists."
That was the most-often heard comment uttered by astronomers at Friday's American Astronomical Society press conference, where the stunning results of the Chandra X-ray Observatory were announced. No doubt it will be heard again and again.
Chandra, launched last July, focuses on the hottest, most violent phenomena in the universe. Its sensitivity is 50 to 100 times that of any previous X-ray telescope. Judging by the orbiting observatory's smorgasbord of discoveries made in just the last six months, Chandra's crusade to study the most extreme objects in the universe will be a long and productive one for astronomy.
Among Chandra's discoveries:
- The first-time detection of X-rays from a black hole 2.6 million times the mass of the sun at the center of our galaxy, the Milky Way
- An unusually "cool" black hole 30 million times the Sun's mass at the center of the Andromeda galaxy
- A mother lode of 2,000 X-ray emitting stars congregated in the center of the Orion Nebula, the richest X-ray field ever obtained
- An extremely oxygen-rich supernova remnant, enough for thousands of solar systems
- A "cauldron" of exploding stars in a nearby galaxy, where short-lived massive stars are being born and dying at a rate far greater than our own galaxy
- A pervasive glow of X-ray radiation across the sky emitted by at least 70 million sources, a third of which are some of the most distant galaxies ever observed
Dr. Claude Canizares of the Massachusetts Institute of Technology (MIT) announced his team's discovery of a ring-like structure of oxygen and neon expanding rapidly through space -- the violent aftermath of a supernova explosion a thousand years ago. Dr. Canizares said the 10 million-degree-Fahrenheit (5.5 million-degree-Celsius) ring contains 10 times the mass of the sun in oxygen alone, enough for thousands of solar systems.
"Supernovae provide much of the oxygen in the universe," said Dr. Canizares. "They might be called fountains of life."
The supernova remnant, E 0102-72, is located nearly 200,000 light-years (1 light-year is 5.88 trillion miles) away in the Small Magellanic Cloud and contains more complex structure and motion than can be explained by current theories. The Chandra results will "challenge the theorists" to testing their assumptions about supernovas, Canizares said.
Dr. Stephen S. Murray of the Harvard-Smithsonian Center for Astrophysics, in Cambridge, Massachusetts relayed his team's discovery of an unusual super-massive black hole in the center of the nearest large galaxy to our own, the Andromeda galaxy, also known as M 31.
Using an instrument aboard Chandra known as the Advanced CCD Imaging Spectrometer (ACIS), the previously known black hole was imaged in X-rays, essentially taking the object's temperature. To their surprise, they found that gas funneling into the black hole was only a million degrees Fahrenheit (555,538 degrees Celsius) -- much lower than what would be expected of a black hole with this much mass.
"We cannot explain what we're seeing by any of the usual models for super-massive black holes," said Dr. Murray. "These observations represent a challenge to our theorist friends that must be explained."
Meanwhile, a black hole resides in the center of our galaxy that is only 2.6 million times the mass of the sun. For the first time, Chandra may have resolved the radio source, known as Sagittarius A*, into X-rays.
Again, ACIS observations show what looks like a faint quasar at the innermost 10 light-years of galactic central.
MIT's Dr. Frederick K. Baganoff, lead scientist for the ACIS team's "Sagittarius A* and the Galactic Center" project, said, "the race to be the first to detect X-rays from Sagittarius A* is one of the hottest and longest-running in all of X-ray astronomy. Theorists are eager to hear the results of our observations so they can test their ideas."
The other Chandra results expose the clutch of hot X-ray emitting stars at the center of the Orion Nebula, the explosive nature of M 82 and the discovery that millions of the most distant galaxies known provide the source of the ubiquitous X-ray background evoked similar comments.
Perhaps what Penn State University's Dr. Gordon Garmire -- head of the team that conceived and built ACIS -- said in reference to Chandra's X-ray background discovery applies to the observatory's task in general: "With Chandra, we are pushing into the Dark Age of the universe."
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