JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
for JPL activities:
Stephanie Zeluck/Comet Chasers Night
FOR IMMEDIATE RELEASE
PLANS COMET HALE-BOPP OBSERVING CAMPAIGN, ACTIVITIES
the orbit of Comet Hale-Bopp (C/1995 O1) brings it closer
to the Sun in late March, NASA and agency-supported scientists
will study the large and bright comet using sounding rockets,
spacecraft and ground-based observations. Using NASA's Hubble
Space Telescope, Hale-Bopp's nucleus was measured at roughly
three to four times larger than that of comet Halley (six
miles in diameter), making it one of the largest comets
ever observed. Researchers are studying Hale-Bopp to better
understand comets, primitive bodies of loosely-packed ice
and dust that many scientists consider the best-preserved
remnants of the early solar system.
agency activities, including a media day for coverage of
the sounding rocket launches, and special Internet home
pages for posting images obtained by NASA missions as well
as amateur astronomers, are outlined below with points of
contact and other relevant information.
Wallops Flight Facility (WFF), Wallops Island, VA, will
conduct four sounding rocket launches starting March 24
through April 5. The missions will be launched for NASA
by the U.S. Navy at the White Sands Missile Range (WSMR),
NM. The payloads, launched on two-stage Black-Brant IX rockets,
will observe the comet in the ultraviolet wavelengths of
light for about five minutes before returning to Earth.
The payloads will be recovered following a parachute descent
at White Sands. Images of the sounding rocket activity at
WSMR will be posted to the Internet at: http://www.wff.nasa.gov/~web/comet.html.
and WSMR will host a media day at White Sands Missile Range
from noon to 4 p.m. MST, March 24. Dr. Alan Hale, co- discoverer
of the comet, will be at the site to speak to reporters.
Media also are invited to cover the 8:15 p.m. MST launch.
For clearance to visit White Sands, call the White Sands
Public Affairs Office (PAO) at 505/678-1134. For more information
on the sounding rocket campaign, call WFF PAO at 757/824-1579.
joint NASA/European Space Agency Ulysses spacecraft, now
in solar orbit, will study what happens to comets as they
are exposed to different solar wind conditions at various
solar latitudes. Hale-Bopp is about to enter the Sun's lower
latitude zone, where solar wind (a continuous outflow of
charged particles streaming from the Sun in all directions
at a million miles per hour) is disturbed compared with
the equatorial regions. Dramatic changes in the comet's
plasma tail are expected to occur at these lower celestial
related observing program, called "Ulysses Comet Watch,"
a collaboration between the Jet Propulsion Laboratory (JPL),
Pasadena, CA, and the University of Colorado, will provide
images from more than 200 amateur observers around the world.
These images will be posted on the Ulysses Comet Watch home
page on the Internet at http://lasp.colorado.edu/ucw/. Observations
will continue to be posted after the comet makes its closest
approach to the Sun on April 1.
Hubble Space Telescope has made a series of observations
of the comet, particularly the nucleus, since September
1995. Hubble cannot observe Hale-Bopp during the next few
months because the comet is too close to the Sun -- Hubble's
sensitive detectors could be damaged if pointed in that
direction. The last observation was made on Oct. 18, 1996,
and the next possible opportunity will be this autumn.
Harold Weaver will publish the results of his observations
with Hubble in the March 28 issue of Science magazine. For
more information, contact the Space Telescope Science Institute
(STScI), Baltimore, MD, at 410/338-4514. Images already
obtained by Hubble are available from the Internet at http://oposite.stsci.edu/pubinfo/PR/95/41.html.
NASA Comet Investigations
Polar spacecraft will make observations of Hale- Bopp
ultraviolet and visible imaging instruments. For more information
call the Goddard Space Flight Center, PAO, Greenbelt,
at 301/286-0697. Images obtained by Polar will be posted
to the Internet
site at: http://pao.gsfc.nasa.gov/gsfc/spacesci/pictures/spacepic.htm
Scientists have been using NASA's Infrared Telescope Facility,
Mauna Kea, HI, to observe Hale-Bopp in the infrared region
of the spectrum. Their observations will be made through
Hale-Bopp's perihelion and continue until summer. For more
information call NASA Headquarters at 202/358-1547.
also will fly a mid-deck experiment on the Space Shuttle
Discovery's STS-85 mission in July. The experiment is the
Southwest Ultraviolet Imaging System, designed to complement
the capabilities of the 5-10 minute sounding rocket flights
by observing the comet more extensively during the Shuttle's
11-day mission. For more information call NASA Headquarters
at 202/358- 1547.
addition, NASA and the National Science Foundation are collaborating
on ground-based observations and analyses of Hale- Bopp.
For information, contact NASA Headquarters at 202/358- 1547.
"Comet Chasers: On the Trail of a Comet" Public
will host a public event called "Comet Chasers: On
the Trail of a Comet" on Friday, April 11, at JPL.
The event is co- sponsored by the Galileo and Stardust projects.
Galileo, which is touring the Jovian system, observed the
1994 Comet Shoemaker- Levy 9 impact on Jupiter. Stardust
will launch in 1999, capture samples of comet dust from
the Comet Wild-2 and return them to Earth for study. Activities
will include a comet viewing session (weather permitting),
and a round-table discussion of the study of comets and
NASA's role in comet studies, featuring David Levy, co-discoverer
of Comet Shoemaker-Levy 9, Dr. Don Yeomans of JPL, and Dr.
Alan Hale and Thomas Bopp, co-discoverers of Comet Hale-
Bopp. The panelists also will discuss NASA's Stardust mission
to Comet Wild-2 in 2004. For more information, call 818/354-5011.
Near-Earth Asteroid Tracking (NEAT) system has also imaged
the comet. Information is available by calling (818) 354-
5011 or checking the NEAT Home Page at: http://huey.jpl.nasa.gov/~spravdo/neat.html.
Sites, Images, Information and Experts
addition to the Internet sites already listed, the
Home Page is a comprehensive information and image resource,
including many images taken by amateur observers. The
A mirror site is: http://galileo.ivv.nasa.gov/comet.
Additional comet information is also available at: http://encke.jpl.nasa.gov
and, for the general public, at: http://encke.jpl.nasa.gov/hale_bopp_info.html.
images and information and links will be posted at
home page at http://www.hq.nasa.gov/office/pao/NewsRoom/today.html.
astronomers who have images of Hale-Bopp in electronic file
format are invited to post their pictures to a NASA web
page at URL: http://comet.hq.nasa.gov/.
Prior to posting, one must first register following the
prompts on that page.
researchers are available for interviews, both in person
and via satellite, at NASA Headquarters as well as GSFC,
WFF, JPL and STScI and other Centers. Contact the respective
Public Affairs Offices for further information.