相关论文: Secular Brightness Trends of Starlink and OneWeb S…
The mean visual magnitude of OneWeb satellites at the standard satellite distance of 1,000 km is 7.18 +/-0.03 . When this value is adjusted to the nominal 1,200 km altitude of a OneWeb satellite in orbit it corresponds to magnitude 7.58…
The mean of 830 visual magnitudes adjusted to a distance of 550 km (the operational altitude) is 4.63 +/-0.02. The data on DarkSat, the low-albedo satellite, indicate that it is fainter than the others by 1.6 magnitudes or 78%. However,…
The mean apparent magnitude and the mean of magnitudes adjusted to a standard distance are reported. The illumination phase function for OneWeb satellites is determined and it differs strongly from that of VisorSat spacecraft. Brightness…
The mean of 430 visual magnitudes of VisorSats adjusted to a distance of 550-km (the operational altitude) is 5.92 +/-0.04. This is the characteristic brightness of these satellites when observed at zenith. VisorSats average 1.29 magnitudes…
A large dataset of visual magnitudes for all three designs of Starlink satellites is analyzed. Brightness phase functions are derived for the Original, VisorSat and Post-VisorSat models. Similarities and differences between the functions…
Magnitudes for the VisorSat and Original-design types were analyzed separately and by time. Mean values are compared with those from other large-scale photometric studies, and some signficant differences are noted. The illumination phase…
Observations of Starlink V2 Mini satellites during orbit-raising suggest that SpaceX applies brightness mitigation when they reach a height of 357 km. The mean apparent magnitudes for objects below that height threshold is 2.68 while the…
Starlink is a low-Earth orbit (LEO) satellite constellation operated by Space Exploration Technologies Corp. (SpaceX) which aims to provide global satellite internet access. Thus far, most photometric observations of Starlink satellites…
Measuring photometric brightness is a common tool for characterizaing satellites. However, characterizing satellite mega-constellations and their impact on astronomy research requires a new approach and methodology. A few measurements of…
The mean apparent magnitude of Starlink Mini Direct-To-Cell (DTC) satellites observed in brightness mitigation mode is 5.16, while the mean of magnitudes adjusted to a uniform distance of 1,000 km is 6.47. The DTCs have faded since early in…
The brightness of Starlink satellites during orbit parking and orbit raising decreased significantly in 2020 when the operator modified their orientation. The mean apparent magnitude before the change was 3.90 +/- 0.18, while afterward it…
A model that combines celestial geometry and atmospheric physics is used to calculate the dimming of artificial satellites as they enter and exit the Earth's shadow. Refraction of sunlight by the terrestrial atmosphere can illuminate a…
The mean apparent magnitude of Starlink Mini Direct-To-Cell (DTC) satellites is 4.62 while the mean of magnitudes adjusted to a uniform distance of 1000 km is 5.50. DTCs average 4.9 times brighter than other Starlink Mini spacecraft at a…
The Steward Observatory LEO Satellite Photometric Survey is a comprehensive observational survey to characterize the apparent brightness of the Starlink and OneWeb low Earth orbit satellites and evaluate the potential impact on astronomy.…
Visual magnitudes and sky coordinates are projected for the full constellation of Starlink satellites. The results are presented in the form of sky maps and numerical tables. Observer latitudes from the equator to 60 degrees are considered.…
A model of the brightness of the visorsat Starlink spacecraft is presented based on published information on the engineering design and from analysis of 131 observations of individual visorsats in late 2020. Comments are offered on the…
Starlink Generation 2 Mini satellites are fainter than Gen 1 spacecraft despite their larger size. The mean of apparent magnitudes for satellites in brightness mitigation mode is 7.06 +/- 0.10. When these magnitudes are adjusted to a…
The development of low earth orbit (LEO) mega-constellation fundamentally threatens ground-based optical astronomical observations. To study the photometric properties of the LEO mega-constellations, we used the Xinglong 50 cm telescope to…
Photometric characteristics for all models of Starlink satellites launched to date are reviewed. The Original design that lacked brightness mitigation is the most luminous. SpaceX installed a sunshade on the VisorSat model which reduced its…
We present observations of 23 Starlink satellites in the $g'$ bandpass, obtained from the Dominion Astrophysical Observatory's Plaskett 1.8 metre telescope. The targets include a mixture of satellites with and without brightness mitigation…