The critical phase of ADEOS ended after the 22nd orbit on August 19 NASDA then began the initial on-orbit check-out of bus system and the mission instruments. The initial mission check-out continued for approximately 90 days, and after which ADEOS was declared ready to ADEOS enter the routine operation phase on November26.
The mission objective of the ADEOS is to accumulate knowledge and understanding necessary to solve the Earth environment issues, especially problems related to global warming, ozone depletion, and terrestrial environmental change. To investigate global warming, ADEOS will observe the elements related to energy circulation and car-bon circulation. It will also observe the ozone variation, especially in polar regions, to facilitate understanding the mechanism of ozone dynamics and related chemical process. In the terrestrial environmental change area, ADEOS instruments will monitor global vegetation distribution and its variation. It also will observe the snow and ice extent and its relation with climate change. ADEOS instruments will provide new data such as global chlorophyll distribution by OCTS, atmospheric temperature and humidity profile and greenhouse effect gases by IMG, and polarization and directionality data by POLDER.
On-orbit check-outs of the mission instruments were con-ducted in parallel with the initial orbital control which placed the spacecraft into the planned orbit at altitude of 800km. The first images were widely reported by major news-papers. These images are accessible on the ADEOS home page(http://www.eorc.nasda.go.jp). In the check-out operations, anmalies were found with ILAS and IMG, but they were solved and all the mission instrument check-outs were completed by October 10.
ADEOS is the first mission of the International Earth Observation System(IEOS) which consists of Earth observation satellite of Japan, US and Europe. ADEOS data will be widely available to any used on the IEOS Data Exchange Principles(DEP) which have been agreed upon by the IEOS participating agencies for the access and use of the data from the IEOS missions. ADEOS data will be available at the lowest possible cost for research and non-commercial operational use for public benefit. In the field of meteorology and fishery, ADEOS NSCAY and OCTS data will be used on a near-real time basis via a network maintained by Japan Meteorological Agency (JMA) and NOAA for numerical weather forecasting; the OCTS data will used by NOAA for coastal environmental monitoring and by Japan Fishery Information Center (JAFIC) for fishing ground forecasting. NSCAT data will be widely used by many meteorological agencies around the world. The network is also widely used fore access by Principal Investigators (PIs) and other users.
NASDA currently distributes OCTS and AVNIR data to PIs for calibration and validation. On December 10, an anomaly was found in the OCTS tilt mechanism while tilts the scanning mirror in the spacecraft flight direction to decrease the effects of sun glitter on the image data. The tilt mechanism was fixed at O degrees on December 17 for the time being which an investigation is underway.
ADEOS provides a variety of data products to users, ranging from radiometric and geometric processed standard data to value added products. The data should be accurate to increase its utility. Most of the mission instruments are in the calibration and validation phase, and their data are avail-able to PIs. NASDA is conducting calibration and validation of AVMIR and OCTS using aircraft, ocean buoys, and in-situ data from the JMA and the Fishery Agencies. NASDA plans to release the AVNIR data and OCTS data to general users in April and June respectively. Other instrument data will also be made available to users from NASDA and individual instrument providers.
NASDA would like to express its sincere appreciation to the agencies and personnel who support this important mission.
