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Panel 1: Space Debris Laser Ranging and the ILRS - how to foster fruitful cooperation

Chairs: Tim Flohrer, N.N.

Today, satellite laser ranging (SLR) to orbital targets is a very well-established technology in the scientific community, for operational satellites equipped with retro-reflectors as well as to the Moon. For a few years the use of this technology has been demonstrated also for the tracking of defunct (space debris) objects, e.g. in order to identify its attitude motion from range residual analysis. While a-priori information and favourable observation conditions are still needed, more sensitive receivers, more powerful transmission systems and improvement of track initialisation techniques allowed to receive and process echoes from uncooperative targets. An increasing number of SLR stations is now able to or plans to participate in coordinated efforts to observe space debris and discussions on the technical but also very important non-technical issues have been started.

In the future laser ranging to also smaller targets may provide a very useful operational alternative for traditional collision avoidance in orbit by acquiring precise orbital data and covariance information in order to reduce the unbearably high false alert rates, As more than 90% of the future collisions will occur between non-operational objects, the next technological step in reach is laser-based momentum transfer, for which feasibility studies are ongoing.

Capabilities to assess the attitude state and attitude motion of satellites have been demonstrated recently. These data need to be processed in collaboration with other (optical and radar) means, and results are essential input for the planning of in-orbit servicing missions, as well as for supporting contingency situations.

In this plenary discussion we want to address needs and ongoing developments and trends related to space debris observations using SLR. We invite participants to address sensors, data processing, data exchange means and formats, as well as reflections on upcoming challenges, and lessons learnt.


Panel 2: The role of the ILRS in the view of many new SLR applications

Chairs: Evan Hoffman, Sven Bauer

Thirty years ago, the ILRS network had less than 10 targets on its tracking list. Today, there are more than 100 targets, and this number is expected to see continued growth. With so many targets, network resources are stretched to their limit, and tracking efficiency is more important than ever.

It is valuable to take a step back and consider the charter of the ILRS and its alignment with our current activities. In our new reality, we would like to explore the role that the ILRS should play in laser ranging activities as a whole, and where its support is most appropriate. Although all ILRS stations are laser ranging stations, the reverse is not necessarily the case. We plan to discuss activities such as space debris, time transfer, and laser communications, and how these fit into our service.

We will also discuss how the ILRS can perhaps play a more active role in network coordination, and what tools can be provided at the network level to improve tracking as a whole (e.g. the GFZ Time Bias service). These will help us use our limited resources more effectively.