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North versus South

Gemini
Gemini North
La Silla

Ground-based telescopes in both hemispheres continue to record ground-breaking images that rival those from their orbiting kin. On June 25, astronomers unveiled the first images from the new Gemini North Observatory (left) near the summit of Mauna Kea in Hawaii. They are some of the sharpest infrared pictures ever produced, thanks to the 8-meter wide telescope's immense resolving power, which at times tops that of the Hubble Space Telescope. Meanwhile, astronomers at the Wide Field Imager, a 67-million pixel digital camera at La Silla Observatory in the Chilean Andes (right), just released some stunning shots of two distant nebulae.

gemini pics

In Hawaii, the Gemini instrument's thin, large mirrors can focus starlight with a precision equivalent to separating car headlights at a distance of 2,000 miles. This enabled it to capture spectacular pictures of distant objects, such as a planetary nebula (left), some ten thousand light years away in the direction of the constellation Cygnus, that was not unlike our own sun several million years ago.

The Gemini Project calls for two such telescopes at a cost of $192 million. "Gemini's innovative optics and thremal controls give these telescopes a significant edge in studying the universe using infrared light," said Matt Mountain, director of the the international project, involving seven nations. Gemini North should start formal scientific operations by mid-2000. It's twin, Gemini South--now under construction atop Chile's Cerro Pachon--will join it the following year.

la silla pic

The second Gemini will be a neighbor to the La Silla Observatory, which is operated by European Southern Observatory (ESO), the Max-Plank-Institut fur Astronomie and the Astronomical Observatory of Capodimonte. On March 25 and 26, it captured several some of the most revealing images yet of two nebulae in the Large Magellanic Cloud (LMC), a galaxy some 170,000 light years away.

The new images are composites based on exposures made using three optical filters, including one centered on the H-alpha spectral line from hydrogen. The red color in the images highlights ionized hydrogen distributed throughout the nebulae, named N44 and N119, and gives some indication of their origins. Red also indicates cooler stars, whereas hotter stars appear blue.

But the earthbound astronomers had better keep their eye's peeled. There will soon be new competition from aloft. An orbiting observatory called FUSE was launched on June 24. It's mission: to test the Big Bang theory and collect the most complete observations yet of the Milky Way's mysterious star-making machinery.

Then, in late July, space shuttle astronauts are scheduled to fire into an orbit more than one-third of the way to the Moon, an x-ray observatory called Chandra. If all goes well, Chandra will allow scientists to obtain unprecedented x-ray images of exploding stars, black holes and other exotic environments to help them understand the structure and evolution of the universe.

North and South; up and down.

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