The first way is to use the antenna as part of a radar system, where it detects orbiting spacecraft and debris and gains information that can be used to better inform spacecraft operators. This is called Space Surveillance and Tracking (SST), and the facility has recently been part of campaigns involving European and International sensors.
The second way is to use the antenna as part of a sensitive receiver, and to make measurements of transmissions from the satellite payload. This is called in-orbit-testing (IOT) and the facility was used to conduct the IOT of ESA’s GIOVE-A and GIOVE-B satellites.
There are millions of objects greater then 1mm in diameter in orbit around the Earth. These include around 1000 active satellites, as well defunct ones and other debris which has resulted from our exploitation of space. Have a look at the following video to see the scale of the situation.
Space debris 1957-2015 (link opens in a new window)
Space surveillance and tracking (SST)
The 25m antenna is host to a new radar that is being developed to provide the UK with additional capability to track and detect spacecraft and debris. The new radar is called CASTR (Chilbolton Advanced Satellite Tracking Radar). It can currently detect targets with Radar Cross Sections (RCS) around 1 square metre in Low Earth Orbit (LEO) out to 2500 km. When the upgrades are completed, it is anticipated that the sensitivity will increase by more than 100 times, and extend its ability to detect micro-satellites and space debris.
2016: STFC has recently joined the UK Space Agency (UKSA), the Ministry of Defence (MoD), NERC’s Satellite Geodesy Facility, Space Insight Ltd, and the Defence Science and Technology Laboratory (DSTL) as the UK’s membership to a European Union (EU) consortium for Space Surveillance and Tracking (EU SST). The full consortium is made up organisations from five member states including France, Germany, Italy, Spain and the UK.
2015: Chilbolton used CASTR in an observation campaign to characterise the re-entry of ESA’s ATV-5 (Autonomous Transfer Vehicle) after it departed from the International Space Station (ISS) in February 2015.
2014: Chilbolton collaborated with DSTL and DSTO (Australian Defence Science and Technology Organisation) to conduct a radar / EO sensor data-fusion experiment. Multiple radar tracks of a number of designated objects were used to generate a ‘better than TLE’ quality cue for EO systems in Australia.
2010/2011: Chilbolton participated in ESA’s CO VI Space Situational Awareness preparatory programme. The radar tracked and detected over 40 satellites over several weeks to demonstrate the radar’s capability to support Europe’s requirement.
The 25m antenna can be used to conduct in orbit testing of satellites. It can measure and evaluate transmissions from global navigation system satellites (GNSS) as they are tracked. Between 2005 and 2011, Chilbolton was funded by ESA to conduct the IOT for the Galileo In Orbit Validation Experiment satellites (GIOVE-A and GIOVE-B).
In January 2006, the Chilbolton Observatory received the first signals from the new GIOVE-A satellite