all Antony Stark stories

'Wintering-over' at the South Pole

70652986 — Mon, 26 Mar 2007 06:26:25 -0400

They came to the South Pole, enduring months of bitter cold, darkness, and isolation, to peer at the galaxy's center through clear, dry skies. And in December, they - scientists from the Harvard-Smithsonian Center for Astrophysics (CfA) - declared "mission accomplished."

After 11 years, the Antarctic Submillimeter Telescope and Remote Observatory, AST/RO, was dismantled last fall. The 1.7- meter telescope was boxed up for transport and now sits on the snow, awaiting a decision on its next stop.

Frequent starbursts sterilize center of Milky Way

70652986 — Mon, 26 Mar 2007 05:36:13 -0400

A scenario in which exploding stars kill all life within the center of our galaxy is detailed by stronomer Antony Stark (Harvard-Smithsonian Center for Astrophysics) and colleagues in the October 10, 2004, issue of The Astrophysical Journal Letters. The team's discovery was made possible using the unique capabilities of the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO). It is the only observatory in the world able to make large-scale maps of the sky at submillimeter wavelengths. The gas for each starburst comes from a ring of material located about 500 light-years from the center of our galaxy. Gas collects there under the influence of the galactic bar -- a stretched oval of stars 6,000 light-years long rotating in the middle of the Milky Way. Tidal forces and interactions with this bar cause the ring of gas to build up to higher and higher densities until it reaches a critical density or "tipping point." At that point, the gas collapses down into the galactic center and smashes together, fueling a huge burst of star formation. "A starburst is star formation gone wild," says Stark. The next starburst in the Milky Way is coming relatively soon, predicts Stark. "It likely will happen within the next 10 million years."

South Pole telescope maps heart of Milky Way

70652986 — Mon, 26 Mar 2007 05:21:54 -0400

Research results obtained by a team of astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) led by Chris Martin and Antony Stark suggest that we are headed for some celestial fireworks. Sometime in the next 300 million years, the galactic center will experience a dramatic burst of star formation and will shine with the light of thousands of newborn suns. The effects of these starbursts will be dramatic. "Many of the stars that form will be very massive and short-lived," says Stark. "They'll quickly use up their fuel and explode as supernovae. Right now, we see one supernova in our galaxy about every 100 years. When the starburst happens, we'll see one supernova every year."

South Pole telescope sees origin of starbursts

70652986 — Mon, 26 Mar 2007 05:09:23 -0400

Astronomers have seen how star formation occurs in the center of our own Milky Way Galaxy by using a telescope based at the South Pole. The observations contribute to our knowledge of how stars form in "bursts" near the center of the galaxy at roughly 500-million-year intervals. The scientists were able to show that a ring of material near the galaxy center contains, on average, several thousand molecular hydrogen molecules per cubic centimeter. This density is near a critical value. If the density is below this value, then the ring can persist as a uniform ring of material in orbit around the galactic center. If additional material is added, however, increasing the density, then the ring will come together under its own gravity and form a giant molecular cloud.