Visibility Analysis of Domestic Satellites on Proposed Ground Sites for Optical Surveillance

Abstract

The objectives of this study are to analyze the satellite visibility at the randomly established ground sites, to determine the five optimal ground sites to perform the optical surveillance and tracking of domestic satellites, and to verify the acquisition of the optical observation time sufficient to maintain the precise ephemeris at optimal ground sites that have been already determined. In order to accomplish these objectives, we analyzed the visibility for sun-synchronous orbit satellites, low earth orbit satellites, middle earth orbit satellites and domestic satellites as well as the continuous visibility along with the fictitious satellite ground track, and calculate the effective visibility. For the analysis, we carried out a series of repetitive process using the satellite tool kit simulation software developed by Analytical Graphics Incorporated. The lighting states of the penumbra and direct sun were set as the key constraints of the optical observation. The minimum of the observation satellite elevation angle was set to be 20 degree, whereas the maximum of the sun elevation angle was set to be-10 degree which is within the range of the nautical twilight. To select the candidates for the optimal optical observation, the entire globe was divided into 84 sectors in a constant interval, the visibility characteristics of the individual sectors were analyzed, and 17 ground sites were arbitrarily selected and analyzed further. Finally, five optimal ground sites (Khurel Togoot Observatory, Assy-Turgen Observatory, Tubitak National Observatory, Bisdee Tier Optical Astronomy Observatory, and South Africa Astronomical Observatory) were determined. The total observation period was decided as one year. To examine the seasonal variation, the simulation was performed for the period of three days or less with respect to spring, summer, fall and winter. In conclusion, we decided the optimal ground sites to perform the optical surveillance and tracking of domestic satellites and verified that optical observation time sufficient to maintain the precise ephemeris could be acquired at the determined observatories.

Analysis of a Simulated Optical GSO Survey Observation for the Effective Maintenance of the Catalogued Satellites and the Orbit Determination Strategy

“…The Optical Wide-field Patrol (OWL) team at Korea Astronomy and Space Science Institute plans to develop five optical satellite tracking sites worldwide. The OWL, an optical satellite tracking network, can be very useful for surveying the GSO region (Kim et al 2011;Park et al 2012).…”

Preliminary analysis of data product of a Korean optical space surveillance system (OWL-Net)

“…The locations of the five observatories were selected by considering with the observation rate for Korean LEO satellites. The observation simulation was done using STK with optical observation condition [1]. Kim et al show that the site located over 30 degree of latitude is more suitable to track the optical tracking of dawn to dusk sun synchronous LEO satellite.…”

Characteristics of Orbit Determination with Short-Arc Observation by an Optical Tracking Network, OWL-Net

“…Monitoring the South Korean geostationary Earth orbit (GEO) region near 128 degrees of longitude is another goal of the OWL-Net. The candidate sites were selected in the light of results for an optical tracking simulation with 11 observation targets of LEO satellites [5]. The OWL-Net can make an observation with a chopper to obtain dozens of measurements per shot [6,7].…”