ESBO DS followed a two-tier approach throughout the entire project: on the one side, the development and construction of a prototype astronomical balloon gondola, including a 50 cm-aperture telescope with a newly-developed UV instrument; and on the other side, the conceptual design of a long-term, balloon-based research infrastructure, prominently including a flight system suitable for carrying a next-generation, 5-m aperture class telescope for far infrared observations. On these two tiers, the following work was performed:
Work performed on the infrastructure concept study:
- Science needs for the mid- and long-term to be addressed by the infrastructure were reviewed and defined;
- The feasibility and benefit of innovative infrastructure technologies, including super pressure balloons, novel flight trajectories, and soft landing systems were studied for the infrastructure;
- Particularly for the balloon gondola / bus, subsystems that could be scaled & built in a modular fashion were studied;
- A conceptual technical design was carried out for three different flight platforms and associated ground systems (including a 0.5 m aperture telescope for UV observations, a 1.5 m aperture telescope for near infrared applications, and a 5 m aperture telescope for far infrared applications);
- Different operations and governance options for a long-term astronomical balloon observatory infrastructure were studied.
Work performed on the prototype development:
- Detailed requirements for the prototype were derived from both the technology demonstration perspective as well as the perspective of a later scientific exploitation of the prototype (primarily for studying variable hot compact stars in the galactic plane);
- Performance simulators for several of the prototype components were developed, including the newly-developed UV-instrument, the secondary visible light instrument (as part of the image stabilization system), the star tracker for guiding, and the Image Stabilization System;
- A thermal simulation model for the prototype at float altitude (~40 km ) was developed to support the design of the thermal control system;
- Test procedures for environmental qualification tests of components for stratospheric balloons were developed;
- A highly precise Image Stabilization System for stratospheric balloons was developed and built;
- A modular and scalable balloon gondola and service subsystems, including payload support systems, were developed and built.
Results achieved:
- Conceptual design for a regularly operating balloon-borne astronomical observatory finished;
- Prototype balloon gondola for astronomical observations in the UV, including a 50 cm aperture telescope, a new-generation UV microchannel plate detector, and a highly precise gondola pointing and image stabilization system manufactured.
Exploitation and dissemination activities carried out:
- Presentation of project results at five conferences;
- (Co-)organization of workshops on balloon- and air-borne astronomy;
- Presentation of results in an Executive Summary and a Development Roadmap;
- Dissemination of results through direct contact with European funding and political bodies.
Further planned exploitation and dissemination activities:
- Test flight of the prototype gondola and telescope preferably in 2022;
- Prototype platform and telescope available for science flights with the microchannel plate detector or other instruments thereafter;
- Preparation of a White Paper;
- Further development of the infrastructure based on the prepared development roadmap.
