Spectroscopy of human-made space objects: from low Earth orbit debris to satellite constellations and exotic outliers

Abstract As the commercial space industry advances, the number of artificial objects orbiting the Earth rises exponentially. To categorize the reflectivity of bright Low Earth Orbit (LEO) objects, a number of spectroscopic observations of such objects was performed in collaboration with the Astronomical Institute of the University in Bern, Switzerland. Supported by laboratory measurements of various aerospace materials, spectra of space objects were analyzed to search for correlations with material samples. On top of that, near-Earth object 2020 SO originally discovered as asteroid was later identified as Surveyor 2 rocket debris. Spectroscopic observation of this object was conducted with the OSIRIS camera-spectrograph at the 10.4m Gran Telescopio Canarias (GTC) located in La Palma (Spain). Spectrum of this object is compared with spectra of upper stage rockets observed by the ZimMain telescope to investigate correlations within their material properties and search for signs of space weathering.