We are informed that the main payload of the launch, the ARGOS satellite, has passed its final (almost) test and that the new launch date is December 17, 1998. The total slip in launch now amounts to more than 3 years - a delay caused by problems in the ARGOS program. This has the unfortunate effect of bringing the mission closer to solar maximum. The Danish Oersted team therefore convened a meeting recently to discuss if further raise of the orbit perigee was needed. Using the same procedure as last time we went through this exercise, the meeting decided to recommend that perigee be raised to "not below 600 km". This means that the launcher target perigee will be app. 620 km.
We are very sorry that this step had to be taken, because we know it will affect the crustal/ionospheric sources science investigations. The driver is not a concern for satellite lifetime, but a requirement of the Attitude Control System (ACS) to keep the orientation of Oersted within certain angles of a set point. With the new perigee altitude, simulations of the ACS using the MSIS86 atmospheric model show that the system can handle f10.7 = 180 (average), with f10.7 = 250 (peak) on the previous day.
Our most recent information on the launch and orbit parameters are shown on the Oersted homepage:
http://www.dmi.dk/projects/oersted/
From:Torsten Neubert (neubert@dmi.dk)
Since you last heard from us, Therese Moretto left the Danish Meteorological Institute (DMI) to take up a position at the Danish Space Research Institute (DSRI), where, as you know, Eigil Friis-Christensen is Director. Negotiations are underway as to how the project should be organized to accommodate the interests of both institutions as well as the interests of the Oersted project. In the mean time, Therese Moretto has stepped down as Oersted Project Scientist, and I have taken on the role of interim Project Scientist in addition to my position as head of the Oersted Science Data Center. The new project administrator is Grethe T. Joergensen (gtj@dmi.dk).