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CAMBRIDGE, Mass. -- A conference featuring many of the world's experts on the life cycles of stars, "Asymmetrical Planetary Nebulae II: from Origins to Microstructures," will be held at the Massachusetts Institute of Technology's Tang Center Aug 3-6, 1999.
Participants will review the latest images and spectra of planetary nebulae, which are stars similar to our sun but are in their final death throes.
Astronomers have expressed renewed interest in planetary nebulae due largely to recent Hubble Space Telescope (HST) images and new data from ground-based observatories. The new information has forced them to re-examine their existing theories concerning the last stages in the lives of stars, said Joel Kastner of the Rochester Institute of Technology, one of the conference organizers.
"The new HST images reveal planetary nebulae to be extraordinarily complex objects that feature a wide variety of shapes and structures," Kastner said. "This complexity and variety presents a challenge to astronomers seeking to understand planetary nebulae in terms of the last stages of 'normal' stars like the sun."
The recently launched Chandra X-ray Observatory (which features instruments and software designed and built in part at MIT), will provide new opportunities to observe planetary nebulae.
Among the speakers are:
- ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½Yervant Terzian of Cornell University and Arsen Hajian of the U.S. Naval Observatory will highlight the most recent results from the Hubble Space Telescope.
- Margaret Meixner of the University of Illinois, who will talk about properties of pre-planetary nebulae, has uncovered some key clues as to how stars expel their outer atmospheres as they die.
- Saul Rappaport of MIT will discuss the likelihood that many planetary nebulae arise out of binary star systems.
- ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½Kastner, a longtime staff member at the Chandra X-ray Science Center at MIT, will describe the motions of the gas ejected from stars as they die, including some exciting evidence for a rotating disk around a dying star.
For more information on speakers and on the conference, see http://space.mit.edu/PN_conf.