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Case for Massive Black Hole Strengthened

UCLA astronomer Andrea Ghez announced more than four years ago that a monstrous black hole resides at the center of our Milky Way galaxy, 24,000 light years away, with a mass more than 2 million times that of our sun. Some astronomers greeted the announcement with skepticism, and proposed exotic forms of matter as alternatives. At the American Association for the Advancement of Science meeting Feb. 16 in Denver, Ghez reported that the case for the black hole has been strengthened substantially, and that all of the proposed alternatives can be excluded.

Planet-Hunting Machine is Getting Even Better

The world’s best planet-hunting machine, the Keck High Resolution Echelle Spectrometer, will be getting even better this year with an advanced imaging array that will improve efforts to detect extra-solar planets, examine distant quasars, measure extragalactic stars and do other research requiring very precise wavelength measurements of thousands of color channels with one exposure. HIRES, a visible-wavelength spectrometer responsible for 20 percent of the science on the Keck I telescope, will be getting an advanced new detector that will increase photon detection rates at ultraviolet wavelengths by a factor of 8 (at 3200 ?), expand single-exposure wavelength coverage, provide finer sampling of spectral features, and allow faster readout rates to provide higher-quality science in less time.

Exceptionally Bright Eruption on Io Rivals Largest in Solar System

Routine monitoring of volcanic activity on Jupiter’s moon Io has turned up the largest eruption to date on Io’s surface or in the solar system. The eruption took place in February 2001, though image analysis was only recently completed by a team of University of California, Berkeley, astronomers. Their results are published in the November issue of the planetary sciences journal Icarus. “The Surt eruption appears to cover an area of 1,900 square kilometers, which is larger than the city of Los Angeles and even larger than the entire city of London,” said the lead researcher. “The total amount of energy being released by the eruption is amazingly high, with the thermal output from this one eruption almost matching the total amount of energy emitted by all of the rest of Io, other volcanoes included.”