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ISSI/IACG-C4 Working Group Activity

The International Space Science Institute (ISSI) is hosting and co-chairing an InterAgency Consultative Group Campaign IV (IACG-C4) Working Group Meeting (small workshop) on "Open and Closed Solar Fields and the Solar Wind". The workshop will be small and hence attendence is by invitation, only. It is scheduled to be held on the ISSI premises in Bern, Switzerland, the week of July 8-12, 1996. (This is the week preceding the COSPAR meeting in Birmingham, UK.)

The suggested subtopics for the workshop are:

KICKOFF MEETING AT SOLAR WIND 8

We would like to have an small, informal "kickoff" meeting among interested
parties during the upcoming Solar Wind 8 conference. This is one of
the few conferences where the solar and space physics communities are in
mutual attendence. We request that the PIs of investigations on the
core and other primary missions (Ulysses, Yohkoh, Solar Ground Observatories,
and Spartan) forward this message to their team members who are
attending SW8 and who can participate in this kickoff meeting.
Representatives of other contributory missions (for example WIND, SOHO,
IMP-8, PIONEER, VOYAGER, CORONAS) are also welcome to attend.

The kickoff meeting will be held on Wednesday, after the SW8 morning
session and business meeting have concluded. The exact time and
place will be announced at the meeting. Please let us know by e-mail
if you are interested in attending, and we may be able to circulate
more information by e-mail prior to arrival at Dana Point.

Best regards,

The Campaign IV Co-Leaders:

Toni Galvin

galvin@umdsp.umd.edu

Hugh Hudson
hudson@isass6.solar.isas.ac.jp

NASA PRESS RELEASE ON ULYSSES

		From:   MX%"NASANews@luna.osf.hq.nasa.gov" 19-JUN-1995 16:23:30.16
		
Subj:   Ulysses Begins Exploration of Sun's Northern Pole
		
		

Doug Isbell
		
Headquarters, Washington, DC 
		
June 19, 1995
		
(Phone:  202/358-1547)
		
		

		Diane Ainsworth
		
Jet Propulsion Laboratory, Pasadena, CA
		
(Phone:  818/354-5011)

		

		RELEASE:  95-96

		

		ULYSSES BEGINS EXPLORATION OF THE SUN'S NORTHERN POLE
		

				The Ulysses spacecraft has begun to explore the
		 northern pole of the Sun, initiating the second phase of its
		 primary mission to study regions above and below the Sun never
		 before explored by spacecraft.
		

				Ulysses, a joint NASA-European Space Agency mission,
		 climbed to 70 degrees north of the Sun's equator at 4 a.m. EDT
		 today.  The spacecraft will spend the next 110 days gathering
		 data on the complex forces at work over this high-latitude
		 region of the Sun, reaching a maximum northern latitude of
		 80.2 degrees on July 31.
		

			   The spacecraft then will begin to journey out to the
		 orbit of Jupiter, returning in September 2000 to the vicinity
		 of the Sun, again at high latitudes.  At that time, during the
		 peak of the Sun's 11-year solar cycle, scientists expect to
		 find a dramatically changed global view of the Sun (the Sun is
		 currently nearing its most inactive or "quiet" phase of that
		 cycle, meaning that fewer sunspots -- massive storms on the
		 Sun's surface -- form in a given period of time).
		

				As the spacecraft begins its pass over the northern
		 polar region of the Sun, scientists are reporting a variety of
		 new discoveries from Ulysses' recently completed pass over the
		 southern pole.  These findings are allowing them to begin
		 assembling a new, three-dimensional picture of the Sun.  Among
		 their latest results:
		

				* Ulysses has verified global differences in the speed
		 of the wind flowing out from the Sun at different latitudes.
		 Most notably, solar winds at high southern latitudes traveled
		 at roughly double the speed found in the equatorial zone.  The
		 solar winds flow at approximately two million miles per hour 
		(800 kilometers per second) at high southern latitudes, while
		 dropping in velocity to about one million miles per hour (400
		 kilometers) near the equator.
		

			   * As the spacecraft approached the equator, the solar
		 wind continued to be very fast until around 20 degrees south
		 latitude, at which time an abrupt transition to the low-speed,
		 low-latitude solar wind was seen.  Large variations in the
		 solar wind speed and other properties then continued until the
		 spacecraft reached 20 degrees north latitude, at which time
		 only the fast solar wind was again observed continuously.
		

				* The loss of material from the Sun over the south
		 pole, caused by the flow of the solar wind, is roughly one
		 million tons per second.  This matter consists of hydrogen,
		 helium and a small fraction of metals and heavy atoms.
		  Results of the southern pass also revealed the outward
		 pressure of the solar wind to be much greater over the pole
		 than it is around the equator.  As a consequence, the shape of
		 the heliosphere -- that region of space dominated by solar
		 particles and electromagnetic fields -- may be elongated in
		 the polar direction, extending much farther out into
		 interstellar space than it does near the equator.
		

				* High energy cosmic radiation entering the inner
		 solar system and, eventually, Earth's atmosphere, from the
		 galaxy is controlled at all latitudes by the level of solar
		 activity, which is determined by each phase of the Sun's 11- 
		year sunspot cycle.   The findings suggest the Sun's control
		 over how much cosmic radiation enters the solar system is just
		 as effective in the polar regions as it is near the equator.
		

				* Plasma waves -- electrical and magnetic fields that
		 result from unstable distributions in the particles making up
		 the solar wind -- play a role in regulating the behavior of
		 solar wind particles and were expected to be found at nearly
		 identical levels in both hemispheres of the Sun.  However, as
		 Ulysses crossed the Sun's equator and entered the northern
		 hemisphere, observations revealed significantly higher levels
		 of several varieties of plasma waves in the northern region of
		 the Sun, compared to their presence in the southern
		 hemisphere.  The cause of this asymmetry is not yet 
		understood, but plasma wave measurements will continue to be
		 used as a diagnostic tool for studying the local properties of 
		the solar wind along the spacecraft's trajectory.
		

				Coordinated observations are under way using Ulysses
		 and a recently launched NASA spacecraft called Wind, designed
		 to study the solar wind flowing between the Sun and Earth.  In
		 addition, these two Sun probes are successfully tracking
		 electrons which stream away from the Sun after the eruption of
		 solar flares in the Sun's outer atmosphere.
		

			   These measurements will allow scientists to map for the
		 first time the magnetic field lines along which electrons
		 travel and provide new insights and observations into large- 
		scale magnetic field structures occurring in the solar wind.
		

				Ulysses also will conduct coordinated observations
		 with NASA's Spartan spacecraft when it is launched later this
		 summer aboard the Space Shuttle.  The aim of these coordinated
		 observations will be to study the distribution of matter in
		 the Sun's outer atmosphere and help engineers design science
		 software for the scientific payload of a future European-built
		 solar probe, known as the Solar and Heliospheric Observatory.
		

				The Ulysses mission is managed jointly by the European
		 Space Agency and NASA to study the regions over the Sun's
		 poles.  The Jet Propulsion Laboratory oversees the U.S. 
		portion of the mission for NASA's Office of Space Science, 
		Washington, DC.
		

								 - end -
		

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