ZARM-Talk: Wie können wir hochpräzise Uhren im Weltall nutzen?

- Der Vortrag findet in englischer Sprache statt - 

Talk by Moritz Huckfeldt
from ZARM, University of Bremen

• Date: 19 June 2025
• Time: 14:00
• Location: ZARM, room 1730

The understanding of our climate and its changes requires a global view of the ever-changing system Earth. This is provided since the early 2000s by the GRACE and GRACE Follow-On satellite gravimetry missions. How can this knowledge be extended and refined in the future?

Improvements of the determination of mass-redistribution processes in the Earth system demands novel measurement concepts and sensors for future satellite gravimetry missions. The utilization of quantum sensors may enhance the precision of measurements and designing new satellite formations can improve the temporal resolution.

Among the quantum sensors, future atomic clocks show significant potential. Theoretically, clocks are predestined for precise determination of the Earth’s gravity field due to the gravitational time dilation related to the gravitational potential. However, clocks also experience a time dilation due to their state of motion. Hence their velocity needs to be known very precisely.

Moritz presents the mathematical foundations for clock observations in satellite gravity field estimation and shows gravity field recovery results from simulated scenarios. He investigates the principle of different mission scenarios and measurement principles, as well as comparing measurements between two or more satellites to determine the feasibility of small satellite swarms. Considering different noise models for the clock measurements and discussing the achievable accuracy of the results, makes it possible to assess how much the development of ultra-stable clocks has to be advanced to enable these kind of satellite missions.