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How do you view a high resolution image on a low resolution screen? Web surfers often encounter poorly-designed web pages that require the user to scroll around an onscreen graphic much too large for their computer monitor. During the last week of October 1998, about 100 scientists gathered in northern Alabama to discuss a similar problem in magnetospheric physics: How do you study the Earth's magnetosphere, with its wide range of spatial and temporal scales, using the poor spatial resolution of today's limited fleet of spacecraft? The answers they came up with were threefold -- use imaging to fill in the gaps, use much larger fleets of spacecraft, and use modeling to tie everything together.

The Sixth Huntsville Modeling Workshop, entitled "The New Millennium Magnetosphere: Integrating Imaging, Discrete Observations, and Global Simulations", was held from October 26 - 30, 1998 at Lake Guntersville Lodge in Guntersville, Alabama. One of the principal accomplishments to emerge from the weeklong workshop was a new definition of imaging, one that includes not only the traditional concept of building pictures by collecting photons, but that also includes detection of energetic neutral atoms (ENA) and the synthesis of large collections of discrete observations (both ground and space based). This new definition was illustrated with results from current research as well as descriptions of upcoming missions, e.g. IMAGE and TWINS, and proposed future missions.

A second principal accomplishment of the workshop was an elucidation of the challenges facing the magnetospheric community. The magnetospheric analyst of the future is faced with a variety of challenges, first because the approaches to studying magnetospheric dynamics will be evolving early in the next decade and second because of mission programmatics in the near future. Important facets of the first challenge include: 1) the poor spatial resolution or distribution of spacecraft within the magnetosphere yielding data sets that are data rich locally but sparse globally, 2) the wide range of scale sizes involved (spatial and temporal), and 3) multiple source and loss mechanisms for magnetospheric plasma with multiple drivers of magnetospheric dynamics (each with multiple candidate mechanisms).

Addressing these challenges will require the use of new techniques and new ways of looking at the magnetosphere, a situation described by one participant as "waiting for Godot". But the community is doing much more than passively waiting for the future. They are actively developing new experimental and theoretical approaches which were discussed throughout the workshop. ENA imaging received much attention, starting with presentation of current images from POLAR/CEPPAD and ASTRID, and continuing with an extended discussion of ENA image inversion techniques. In addition to neutral atom imaging, presentations focused on Radio Plasma Imaging, a new technique that will be flown for the first time on the IMAGE mission. This technique involves sending out radio wave packets in all directions and measuring the time delay, arrival angle, amplitude, and Doppler shift of reflected echoes. The concept of imaging was further redefined to include synthesis of discrete observations, either from arrays of groundbased instruments, or new fleets of satellites such as those proposed under the Magnetospheric Multiscale and Magnetospheric Constellation missions. For example, a number of techniques were reviewed that used particle data, obviously collected in-situ, but whose interpretation defined conditions remotely. Particle distributions have been used to test magnetic field models, and the non-gyrotropic distributions due to the large gyroradius of high energy particles have been used to detect the location and motion of boundaries, especially the magnetopause.

In short, imaging was defined to be any technique that synthesized information from a large region of space with sufficient resolution to yield results quantitative enough to address current problems in magnetospheric science. The question facing us today is, will such approaches be sufficient, and are we as a community up to the challenge of using these newly defined 'images'?

With some exceptions for low-cost missions, single satellites with in-situ measurements have gone about as far as they can in providing unique data. The large complements of instruments on any one satellite that provide complete characterizations of the plasma environment are phasing out. With the ISTP missions ending early in the next decade, a new and different type of fleet of simultaneously operating spacecraft will be launched, many of which will be carrying imagers of various types. Groups of satellites will be launched that contain common, but limited sets of in-situ measuring instruments. Thus the analyst must become familiar with different types of data sets that demand different analysis techniques. Imagers will provide large scale characteristics of plasma regions from which time-dependent representations of plasma characteristics should be able to be derived. Fleets of common satellites will provide, in theory, the capability of separating spatial and temporal phenomena. With these new data sets the analyst will face two fundamental challenges: 1) Can sufficiently quantitative parameters be derived from the data, especially images, which will allow a distinction to be made between various candidate source, loss, and driver mechanisms? and 2) Can the physics of the dynamics be derived from such databases, especially from the fleets of satellites with more limited instrumentation?

Space plasma physics, and magnetospheric physics in particular, is a maturing field. Seldom is a new frontier exposed. Thus the identification of compelling science for new missions becomes more difficult. The ultimate question to be asked is: "When the mission is over, what new understandings will we have?" With the compression in the mission operations and data analysis period, the time lag from launch to maximum science productivity must be reduced. History has shown three to five years, but this must be reduced to two years or less. Thus the utilization of the new types of data, in particular the inversion of image data and the rapid access and visualization of large volumes of data from arrays of spacecraft must be prepared before launch.

A final challenge facing us is communicating scientific findings outside the immediate scientific community. With that challenge in mind, the workshop included a special 'virtual' outreach session. Scheduled throughout the workshop were talks and presentations on dealing with the public, students, and the media.

Can the magnetospheric community meet these challenges? The next few years are critical, because how we approach the challenges in that time will produce the roadmap for implementation.

The meeting conveners are grateful to all the participants for making the meeting a success. We are also grateful for the input provided by session chairpeople for this article. More details of the meeting and the attendees can be found online at http://science.msfc.nasa.gov/ssl/pad/sppb/workshop/default.htm.