In celebration of Astronomy Day on May 10, the Space Telescope Science
Institute is unveiling one of the largest mosaic images of a celestial
object ever taken by NASA’s Hubble Space Telescope. The colorful
ring-shaped Helix Nebula is Hubble’s latest picture-perfect target.
Poster-sized prints will go on display at 22 select science museums,
planetariums, and astronomy clubs throughout the United States and
Canada as part of Astronomy Day festivities. Internet surfers will be
able to come to the Space Telescope Science Institute’s Hubblesite
Newscenter (at http://hubblesite.org/newscenter) to download the image
in full resolution, or simply as computer wallpaper. Beginning May 5,
Hubblesite visitors will also be able to test their astronomy skills
by playing an online astronomy quiz hosted by our Astronomy Day mascot,
“Milky the Cow.” The space quiz is available in three versions for the
entire family: “novice,” “pretty smart,” and “astro-brainiac.”

The Helix Nebula is a popular target of amateur astronomers. This
expanding shell of a nearby dying star can be seen as a ghostly,
donut-shaped object in the constellation Aquarius. The nebula’s angular
diameter is one-half the diameter of the full Moon, so Hubble
astronomers had to take several exposures with the Advanced Camera for
Surveys to capture most of the sprawling nebula. Valuable Hubble
observing time became available during the November 2002 Leonid meteor
storm. To protect the Hubble spacecraft and its precise mirror,
controllers turned Hubble’s aft end into the direction of the meteor
stream for about half a day. Fortunately, the Helix Nebula was almost
exactly in the opposite direction of the meteor stream, so Hubble used
nine orbits to photograph the nebula while it waited out the storm.

To make a poster-sized version of the Helix Nebula image, the Hubble
data were carefully processed to smooth out seams between pictures.
The image was then combined with a wider, ground-based telescopic
image from the National Optical Astronomy Observatory in Tucson,
Arizona.

Electronic image files and additional information will be available at
http://hubblesite.org/newscenter/2003/11.

The Space Telescope Science Institute (STScI) is operated by the
Association of Universities for Research in Astronomy, Inc. (AURA), for
NASA, under contract with the Goddard Space Flight Center, Greenbelt,
MD. The Hubble Space Telescope is a project of international
cooperation between NASA and the European Space Agency (ESA).