3. November 2020

Space Science at Droptower SEMINAR TALK

Location: ZARM Bremen - Online seminar
When: 3.11.2020, 16:00 CET - Online

Speaker: Matthias Weigelt (Leibniz Universit├Ąt Hannover)
Title: Low-low satellite-to-satellite tracking: from geometry to gravity

Abstract: GRACE-type satellite missions are implementations of the low-low satellite-to-satellite tracking concept, where two (or more) low-orbiting satellites observe their relative motion. GRACE and GRACE-Follow On provide along-track inter-satellite ranging information using K-Band or LRI ranging information. Evaluating the variations in the ranging information allows to recover the gravity field and its temporal variations. As the ranging is a geometric observation by nature, the connection to gravity is not intuitive. The presentation will show the necessary derivations to fully understand the geometry of a GRACE-type mission and presents ways to connect the observations to gravity field quantities for precise modelling. We will also look at the orbit geometry to understand the observed limited sensitivity in the East-West direction.