Subject: [SLR-Mail] No. 80: To Conclude RIS Experiment From: H. Kunimori, CRL/Japan <[Mailed EDC ]> ******************************************************************************** SLR Electronic Mail 1997-09-10 12:00:00 UTC Message No. 80 ******************************************************************************** Author: H. Kunimori, CRL/Japan Subject: To Conclude RIS Experiment September 10, 1997 Dear colleagues, We thank you very much for your cooperation in SLR to the ADEOS satellite. As was announced by NASDA, the ADEOS satellite had a serious malfunction on the solar paddle, and the satellite has been no longer operated since June 30. We have continued observing sun lit image of the satellite and trying laser ranging to the RIS. But it turned out to be difficult to obtain laser return from the RIS, because it is difficult to predict the attitude of the ADEOS. Considering this situation, we would like to conclude the experiment using the RIS. Though the period of operation of the ADEOS was short, we have obtained some valuable results with the RIS experiment. - The RIS was the largest single element hollow corner cube with a special surface design. We confirmed it worked perfectly in orbit. - We succeeded in active tracking of the RIS using visible return. We obtained tracking accuracy of better than 30 micro radians both in daytime and nighttime. - We measured absorption spectra of ozone using TEA CO2 lasers. This was the first spectrum measurement with the laser long-path absorption method between the ground and a satellite. We validated the measurement by comparing with a simultaneous heterodyne spectrometer measurement. - We have obtained a series of data useful for error analysis of the earth-to- satellite laser long path absorption method. These experiments were carried out using the orbital prediction based on the SLR support. Although no further tracking request will be issued from us, we will continue to generate TIRV for next 6 months to who try optical tracking for Engineering and Test purposes. We would like to thank you again for your cooperation. Sincerely yours, Nobuo Sugimoto RIS Science Team Leader sugimoto@sun51b.nies.go.jp Hiroo Kunimori RIS Tracking Support Coordinator, CRL kuni@crl.go.jp and Masao Hirota, National Space Aganecy of Japan hirota.masao@nasada.go.jp [Mailed From: EDC ] ********************************************************************************