ESA Science & Technology - Publication Archive
This special issue of Annales Geophysicae presents the mission, the instruments and the first results of the Double Star programme. Double Star is the first mission in collaboration between China and ESA. Double Star has been a great opportunity for the European and Chinese scientists to enhance the knowledge of the Sun-Earth connection. Double Star, together with Cluster, brings six coordinated spacecraft to study small-, medium- and large-scale plasma processes in geospace. This is the first time that European instruments have been flown on a Chinese spacecraft as part of the payload.
Per Tegnér, Chairman of Council
- 4th Announcement of Opportunity (AO-4)
- The INTEGRAL Users Group
- INTEGRAL Mission Status
- Science Highlights
- Galactic Bulge Monitoring Program
- Science Operations - Highlights
- The ISOC Science Data Archive
- The 6th INTEGRAL workshop
- ISOC now at ESAC
- Contact INTEGRAL science operations
The Venus Entry Probe study is one of the European Space Agency's (ESA) technology reference studies. It aims to identify; the technologies required to develop a low-cost, science-driven mission for in-situ exploration of the atmosphere of Venus, and the philosophy that can be adopted. The mission includes a science gathering spacecraft in an elliptical polar Venus orbit, a relay satellite in highly elliptical Venus orbit, and an atmospheric entry probe delivering a long duration aerobot (aerial robot) which will drop several microprobes during its operational phase.
The atmospheric entry sequence is initiated at 120 km altitude and an entry velocity of 9.8 kms-1. Once the velocity has reduced to 15 ms-1 the aerobot is deployed. This consists of a gondola and balloon and has a floating mass of 32 kg (which includes 8 kg of science instruments and microprobes). To avoid Venus' crushing surface pressure and high temperature an equilibrium float altitude of around 55 km has been baselined. The aerobot will circumnavigate Venus several times over a 15-22 lifetime analysing the Venusian middle cloud layer. Science data will be returned at 2.5 kbps over the mission duration. At scientifically interesting locations 15 drop-sondes will be released.
This paper focuses on the final mission design with particular emphasis on system level trade-offs including the balloon and pressurisation system, communications architecture, power system, design for mission lifetime in a hostile and acidic environment. It discusses the system design, design drivers and presents an overview of the innovative mission-enabling and mission-enhancing technologies.