An Open Letter to the Solar Physics Community on TRACE DATA Access One feature of the TRACE mission is the open data policy. The purpose of this letter is to clarify this policy and to encourage a dialog on how to insure its fair and reasonable implementation. Our fundamental data policy is simple: All TRACE data will be equally available to everyone on the World Wide Web. An open data policy is an experiment for Solar Physics space experiments. There will be misunderstandings that cause varying degrees of unhappiness. There is no perfect policy and it is naive to expect that deviations from established practice will not result in some problems. TRACE is currently scheduled to be an 8 month science mission. As a result the initial science priorities must be carefully planned and executed. There is in place a detailed plan for the first 30 days of science operations, which is available on the web. It will probably take longer than 30 calendar days to execute this program. The outline of the full 8 months of science operations is currently under development. Many of the science objectives of the planned investigations will be greatly enhanced by the coordination with other instrument teams both in space and on the ground. TRACE will be operated in daily coordination with the SOHO mission from an Experiment Operations Facility (EOF) adjacent to the SOHO EOF. TRACE co-investigators are members of the SOI/MDI, CDS, EIT, and YOHKOH experiment teams and are experts in the scientific and operational capabilities of these instruments. Other co-investigators are responsible for major groundbased facilities. We are now working on joint observing programs with other missions that can enhance the scientific output of the TRACE data set. We encourage all participants in joint observing programs to make all data obtained in TRACE joint observing programs available to everyone as quickly as possible. We can not, however, guarantee it as the collaborators may not have an open data policy. The TRACE data catalogs will have pointers to joint observing data of other instruments and the catalog will indicate the requirements of other experiments for data usage. TRACE data will be transferred after station passes to a data archive that will maintain a large fraction of the TRACE data set on line for ftp transfer. Data will be requested via a web form. The form will have windows that include a statement of scientific objectives, the estimated date of completion of the investigation, and whether the data is being used as a part of a PhD thesis. All information beyond that of the request of a specified data set is optional. A catalog of all data transfers and scientific program objectives will be maintained on the TRACE website. In order to use the TRACE data effectively there will be a TRACE Analysis Guide on the web. This guide will contain descriptions of the data organization, data catalogs, and descriptions of the TRACE calibration procedures. It will also contain descriptions of, and pointers to, the TRACE image calibration software, tested analysis software, and user contributed software. Because TRACE is complex instrument there will always be a TRACE scientist available to provide aid in starting science investigations. The personal aid will be implemented via e-mail, phone, and direct contacts. Our belief is that the vast majority of the science community will agree that quick general release of science data is a goal worth working toward. We hope that TRACE data users share data together with an open mind and assume that perceived unfairness or improper usage of data is accidental, so that difficulties be resolved before they become serious problems. Alan Title

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(Lockheed Martin Missile & Space)		(The Lockheed Martin Solar and Astrophysics Labs)
Dr. Neal Hurlburt email: hurlburt@sag.lmsal.com