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Two views of the 3-D image of the neutral gas in the Helix nebula
-front and from below. The nebula is shown as a statue-like structure
illuminated from the rear, so the darker areas are nearer.These views were made from observations with the 10.4 meter telescope of the Caltech Sub-millimeter Observatory, Mauna Kea, HI, and were presented to the American Astronomical Society meeting in Austin, TX on January 6, 1999. PHOTO CREDIT: P. J. Huggins, K. Young. (Full size image available through contact) |
A team of astronomers have developed a 3-D globe-like image of the Helix nebula (NGC 7293), a planetary nebula located 500 light years away in the constellation Aquarius. The astonomers' 3-D image of the nebula -- which is based on data from the Caltech Sub-Millimeter Observatory -- allows the team to inspect it from all sides: front, back, sides, top and bottom. Based on this inspection, they have proposed an explanation for the nebula's characteristic shape.
(Note: two views of the 3-D image are attached to the press release. The image
can also be obtained at www.physics.nyu.edu/faculty/huggins/index.html.
Close analysis of the image reveals evidence that the Helix nebula behaves much like a double-headed garden sprinkler. For each blob of gas ejected on one side of the nebula, there is a similar structure being ejected on the opposite side. The researchers say this behavior is likely caused by a nearby star that is affecting how the dying Helix star ejects its outer layers.
NYU physics professor Patrick J. Huggins said, "Using data from a radio telescope, we have essentially developed a globe of the Helix nebula. Our 3-D image allows us to closely examine this dying star from a variety of perspectives: front, back, sides, top and bottom. These observations are significant in revealing the true shape of the Helix and in suggesting how the nebula was formed."
These observations are being presented at the 193rd meeting of the American Astronomical Society in Austin, Texas, by Patrick J. Huggins of New York University, Ken Young of the Smithsonian Astrophysical Observatory, Pierre Cox of the University of Paris (France), Thierry Forveille of the University of Grenoble (France), and Rafael Bachiller of the Observatorio Astronomico Nacional, Madrid (Spain).
In contrast to earlier optical photographs, this 3-D image was generated from data collected by a radio telescope. Each pixel represents carbon monoxide molecules that form part of the nebula's envelope. These molecules were observed at a wavelength of 1.3 millimeters, which corresponds to a frequency of 230 Gigaherz. The telescope used was the 10.4 meter telescope of the Caltech Sub-Millimeter Observatory, located on Hawaii's Mauna Kea (13,800 ft).
This research is supported in part by the National Science Foundation.