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Latest News About ISSAC™ Success! (Partially) After many years of development and testing followed by a launch last November, ISSAC installation by astronauts was finally completed May 31, 2009 and checkout of the system in orbit could begin - an exciting time for all of us! During April and May there were several challenges overcome during astronaut installation. Our first order of business was to check out system communications and monitoring. Commands from our Operations Center at UND do reach the sensor onboard the International Space Station and we can monitor system operation and receive telemetry from it. As we proceeded through our checkout though, some operational anomalies presented themselves, which needed to be cleared up before routine operations could begin.   Science Operations Center (SOC) at the University of North Dakota Challenges Overcome As of Monday, April 20th, the International Space Station Agricultural Camera (ISSAC) personnel, NASA and astronauts onboard the International Space Station (ISS) believed they had completed the installation process and were prepared to initiate testing and operations.   Pictures of ISSAC installation aboard the ISS However once the ISSAC payload was powered for the first time, student operators at UND discovered an unexpected anomaly while viewing the ISSAC Health and Status data [see pic below].   (Left) Health and Status Telemetry; (Right) Commands/Communication System After extensive troubleshooting - which involved ISSAC operators at UND, NASA personnel at both Houston TX and Huntsville AL, astronaut Michael Barratt in orbit, and a second powered operation on April 30th, it was determined that a problem with the NASA-supplied laptop was likely. Detailed technical procedures were written to accomplish this, and over Memorial Day weekend (Saturday May 23rd) astronaut Michael Barratt replaced the NASA laptop. The ISSAC team then repeated the process of powering on and the original problem was determined to now be fixed.   Astronaut Mike Barratt helping fix ISSAC anomalies However, even with the new laptop a new anomaly was detected, which ISSAC operators traced to a loose cable. Again astronaut Mike Barratt was called upon to remedy the situation; he re-secured the cabling and official ISSAC operations could begin. Current Status "Third time's the charm" didn't quite work for ISSAC. After these first two problems were solved, we were finally able to start operating the sensor. Everything seems to work, except there are abnormalities when we attempt to take an image. We have gone through several troubleshooting steps, are currently reviewing results, and hope to soon have the problem resolved. Crew members are now currently busy preparing for the arrival of the next shuttle, but we can get more of Mike Barratt's time later in June should we need astronaut assistance again. Next Steps We have successfully resolved two on-orbit anomalies so far, and gained some operational seasoning in the process, which bodes well for eventually figuring out this last one. Unfortunately given the late date, and even if we have a quick resolution of the current problem, routine operations of ISSAC are not expected to begin this growing season. At this time we do expect the problem to be resolved such that we can complete our on-orbit checkout and imaging characterization, and perhaps have some limited operations later this year. If you have indicated your interest in getting data in the past, we will keep your name on our list and let you know when ISSAC is expected to be operational. If you have yet to register and would like to be kept informed of ISSAC progress, please do so here. Prior News About ISSAC
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ISSAC Initial Activation