Our research basically originates from two classical branches of astronomy that evolved into numerous space techniques and applications. The first one includes dynamics of the artificial satellites that orbit planetary bodies and that collect a lot of information about that bodies. In this way we primarily study Earth's outer environment like the upper atmosphere, the gravitational and geomagnetic field. Our other concern originates from terrestrial space observation that for example contributes to star catalogues, our knowledge of the Earth's orientation parameters (EOPs), planetary rotation etc. The group resides at two sites of ASI (inPragueand inOndřejov - a small village 30 km far from Prague). People working on Earth's rotation & EOPs can be found in Prague while people from artificial satellites are mostly seen in Ondřejov.