Jan-Christian Meyer, Berlin Space Technologies GmbH
Ashvij Narayanan, Berlin Space Technologies GmbH
Andreas Wiegand, Astos Solutions GmbH
Jan-Christian Meyer, Senior Systems Engineer, Berlin Space Technologies GmbH
Satellite applications in very low earth orbit (VLEO) have been investigated in the literature for a long time. One of the very few realised missions is GOCE to measure Earths gravity potential. It is evident that there is a discrepancy between theoretical possibility and the practical implementation.
One of the reasons have been the high satellite and launch costs. With the NewSpace approach this hurdle is getting lower. New business models become viable. Today, various startups and established companies are developing platform, satellite and mission concepts for VLEO. This includes funding by the European Defence Fund. It is thus evident, that VLEO applications have important potential that originates in the close proximity to Earth: For Earth observation the shorter distance increases resolution. For communications, signal time-of-flight is reduced.
For these reasons, Berlin Space Technologies (BST) is performing an investigation into the feasibility of an industrialised VLEO satellite platform. The present paper will introduce the study and outline first mission scenarios that are investigated.
Contrary to past approaches that focus on the application and derive mission and system requirements in the classical systems engineering way, the approach in the given study focuses on industrial viability. This means that the starting point for the investigation is BST’s LEOS satellite platform. A primary question to be answered is which application and mission scenarios are possible with the LEOS platform when adapted to VLEO. The resulting trade-off balances operational benefit of a given scenario against the cost of adapting an existing technology.
This trade-off varies parameters such as payload type, performance and resource needs, VLEO altitude, mission duration and constellation size.
Various mission scenarios are investigated in an open-minded approach. Several dedicated VLEO concepts are derived. One concrete VLEO business case that they are compared against is a VLEO extension of a LEO satellite. The idea is to operate a commercial Earth observation satellite at classical LEO altitude. After its end of life or at the request of a high-value customer, the satellite’s altitude is reduced to VLEO to increase its performance (e.g. optical resolution). Here, the satellite can operate for a given amount of time before it re-enters the atmosphere. In this scenario the satellite is not fully optimised for operations in VLEO. this will limit its orbital lifetime, but at the other hand also enable other commercial benefits by increasing the number of satellites built on the same platform.
Other scenarios leverage the modular nature of the LEOS platform to investigate to which extent a dedicated VLEO platform is a viable option. The ability to modularly change the capacity of the electrical power subsystem and accommodate multiple different propulsion systems enables an optimisation of the mission design parameters.
The study is funded through the DLR Raumfahrtagentur and will last for almost two years. This paper presents the first phase of the project. In subsequent phases, promising mission and system scenarios will be investigated in more detail before a single baseline will be designed up to production readiness at the end of the study.
BST is supported in this work by Astos Solutions GmbH who contribute their capabilities in orbital mechanics, mission analysis and the interactions between the VLEO atmosphere and the spacecraft.