There's been so much interest in Hale-Bopp, I thought you all might be
interested in this press release as well.

Peggi


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>Date: Thu, 3 Apr 1997 15:00:38 -0800 (PST)
>From: JPL Public Information Office <JPLNews at jpl.nasa.gov>
>To: news-release at www-onlab.jpl.nasa.gov
>Subject: Stardust team studies Hale-Bopp's cometary cousin
>Sender: domo at www-onlab.jpl.nasa.gov
>
>PUBLIC INFORMATION OFFICE
>JET PROPULSION LABORATORY
>CALIFORNIA INSTITUTE OF TECHNOLOGY
>NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
>PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
>http://www.jpl.nasa.gov
>
>Contact: Jane Platt
>
>FOR IMMEDIATE RELEASE April 3, 1997
>
>NASA'S STARDUST TEAM STUDIES HALE-BOPP'S COMETARY COUSIN
>
> Just as Comet Hale-Bopp continues its journey across the
>nighttime sky, another currently visible comet, Wild 2, is
>capturing the attention of NASA's Stardust Project for a vitally
>important reason.
>
> Stardust, a spacecraft with a planned 1999 launch, will
>capture samples of comet dust from Wild 2 in 2004 for return to
>Earth in 2006. This current appearance by Wild 2 (pronounced
>"Vilt 2"), offers the Stardust team a prime opportunity to
>prepare for the spacecraft's historic journey by gathering data
>on the comet's brightness and the size and quantity of its gas
>and dust particles.
>
> The spacecraft is protected from oncoming cometary particles
>with a front "Whipple Bumper," a shield named for renowned
>astronomer Fred Whipple, with a composite structure that includes
>metals and several curtains of the same material as bullet-proof
>vests. However, the bumper does not offer unlimited protection
>against a barrage of numerous, large particles.
>
> "We want to study the dust envelope of Wild 2 so we'll know
>how close we can fly without jeopardizing the spacecraft," said
>Stardust Project Manager Dr. Kenneth Atkins. "These current
>observations will help us significantly reduce the risk."
>
> By observing Wild 2 in both visible and infrared light, the
>Stardust team will be able to fine-tune models of the comet
>environment and mission logistics. Final trajectory adjustments
>may be made up to a few hours before encounter, using
>observations made by Stardust en route to Wild 2. That encounter
>will take place on January 2, 2004, about 98 days after the
>comet's perihelion, or closest pass by the Sun. During Wild 2's
>current visit, scientists will study the comet's activity at a
>comparable post-perihelion point, gathering data crucial to the
>success of the Stardust mission.
>
> Wild-2 studies are being conducted at numerous
>observatories, including Lowell Observatory, Flagstaff, AZ; the
>Lunar and Planetary Laboratory, University of Arizona, Tucson;
>the W.M. Keck Observatory and other major telescopes atop Mauna
>Kea, HI; and the 200-inch Hale telescope at Palomar Observatory
>near San Diego, CA. Amateur astronomers can see Comet Wild 2
>with a relatively small telescope through August, with the best
>viewing before the end of May. With an apparent magnitude of
>9.6, Wild 2 is currently visible almost directly overhead about
>one hour after sunset and is located in the constellation of
>Cancer close to the Praesepe open star cluster.
>
> Comet Wild 2, a short-period comet with a six-year orbit,
>was discovered in 1978 by the Swiss astronomer Paul Wild, after
>its close encounter with Jupiter in 1974. This may have been the
>comet's first journey to the inner solar system in recent
>centuries, which means it is in a more pristine state than other
>comets which have been "around the block" more often. For this
>and several other reasons, Wild 2 was chosen as the destination
>comet for Stardust.
>
> As Atkins explained, "Wild 2's orbit presents attractive
>features for doing a sample return. The comet will be in the
>right place at the right time so that when Stardust encounters
>it, Wild 2 will have a relatively low flyby speed of 6 kilometers
>per second (3.7 miles). This makes the task of catching the
>comet dust as it whizzes by much easier. In addition, the
>orbital geometry of Wild 2 enables us to save money by launching
>Stardust on a Delta rocket and designing an efficient
>trajectory."
>
> To capture the comet dust without harming it, Stardust will
>use aerogel, a spongy, silica-based solid with 99 percent empty
>space. The tiny cometary particles will bury themselves in the
>transparent aerogel, awaiting retrieval by scientists on Earth.
>On its way to Wild 2, Stardust will loop twice around the Sun and
>collect interstellar dust particles. By returning these space
>and cometary materials to Earth, Stardust will mark the first
>space sample return mission since the Apollo missions collected
>moon rocks in the 1960s and 1970s.
>
> Stardust co-investigator Ray Newburn said comets are
>apparent leftovers from the formation of the solar system and may
>unlock many cosmic secrets. As he put it, "Comets are a
>different sort of beast. They've been in a cosmic deep-freeze
>for most of the solar system's 5-billion-year history. Many
>scientists believe comets added complex organic molecules to the
>primordial soup of oceans that helped form life. Stardust should
>give us some hard facts about Wild 2 and other comets, including
>chemical composition and age."
>
> Stardust is one of NASA's Discovery missions, which team the
>agency with industry and universities to launch low-cost
>spacecraft in a short time frame with highly-focused science
>goals. Stardust's principal investigator is Dr. Don Brownlee of
>the University of Washington, Seattle, WA.
>
> The Stardust spacecraft and sample return capsule are being
>built by Lockheed Martin Astronautics in Denver, CO. The mission
>is managed by NASA's Jet Propulsion Laboratory for NASA's Office
>of Space Science, Washington, DC. JPL is also developing the
>aerogel and the spacecraft's navigational camera, also to be used
>for scientific imaging. Stardust's cometary and interstellar
>dust analyzer instrument is provided by Jochen Kissel through the
>Max Planck Institute in Germany; the University of Chicago, IL,
>is building a Whipple Shield dust impact counter.
>
> Additional information is available on the Stardust home
>page on the World Wide Web at:
>http://pdc.jpl.nasa.gov/stardust/home.html.
>
> #####
>4/02/97 JP
>#9733
>.-
>
>
Ben & Peggi Rodgers
Aptos, CA (near Santa Cruz 122 W, 37 N)
USA
woodduck at cruzio.com


"A bird does not sing because it has an answer,
It sings because it has a song"