After months of preparation, integration tests and operational simulations, European Space Agency(ESA) is all set to launch its new earth observation satellite Sentinel-2B on 7 March 2017 at 01:49 UTC (02:49 CET). The satellite will be injected into orbit from Kourou, French Guiana to complete the constellation and shift the Sentinel-2 mission into high gear.
Sentinel-2B was shipped to Kourou in early January, where it has been tested, fuelled, encapsulated in its Vega rocket fairing, rolled out to the launch pad and hoisted into the tower Carrying a multispectral camera to image Earth’s changing land and vegetation.
As the fifth satellite of Europe‘s environmental monitoring programme Copernicus Sentinel-2B mission is equipped with high-resolution Multispectral Imager with 13 spectral bands to cover every spot on the earth. The mission is a close collaboration of European Commission, an industrial consortium of about 60 companies led by Airbus Defence and Space, France’s CNES space agency and the Copernicus service providers.
About Sentinel-2B launch
Sentinel-2B is the next important milestone in Europe‘s Copernicus programme. The satellite will join its twin, Sentinel-2A, which has been in orbit since June 2015. With circling on opposite sides of Earth and providing 290 km-wide coverage.
To avoid any risk of collision with the already-in-orbit twin, Sentinel-2B will be injected into an orbit 11 km below the final, desired orbit. To make the plan successful the team will have to plan for a ‘raising manoeuvre sequence’ in order to bring the satellite into its final orbit. And, that is going to keep the team busy for three days around the clock.With the launch of Sentinel-2B the time will be cut in half to five days, and to just three days over Europe to take the image of the globe. With just one satellite Sentinel-2A the present earth observation duration is 10 days.
With the launch of Sentinel-2B the time will be cut in half to five days, and to just three days over Europe to take the image of the globe. With just one satellite Sentinel-2A the present earth observation duration is 10 days.
Sentinel-2B is part of ESA’s Sentinel mission
Twin sisters, Sentinel-2A and 2B belong to the family of ESA’s Sentinel Mission. In close collaboration with Copernicus, each Sentinel mission is based on a constellation of two satellites to fulfill revisit and coverage requirements, providing robust datasets. These missions carry a range of technologies, such as radar and multi-spectral imaging instruments for land, ocean and atmospheric monitoring:
Comprising a constellation of two identical polar-orbiting satellites following the same ground track, and separated by an argument of latitude difference of 180°. The Sentinel-2 orbit crosses the equator at a specific time of day (10:30 local) so as to guarantee the best illumination conditions for the optical acquisitions of the main instrument, the MSI.
Sentinel-2 is a polar-orbiting, multispectral high-resolution imaging mission for land monitoring to provide, the imagery of vegetation, soil and water cover, inland waterways and coastal areas. The applications of the mission are numerous, ranging from agriculture to forestry. Sentinel- 2 data can be used to map changes in earth coverage and monitor the world forest. It also provides information about lake pollution and coastal water pollution. Sentinel satellite also plays role in providing information in civil security by monitoring floods, volcanic activities, and landslides which can be used for humanitarian relief efforts during disasters.
Vega-The launch window
Sentinel-2B will be lifted-off on the Vega Launcher. To achieve this orbit and target the 10:30 local time, the Vega launcher can lift off at only one moment in the day. Vega launches from Europe’s Spaceport in Kourou, French Guiana, and is designed to be launched toward the north from Kourou, so as to facilitate recovery of the boosters over open ocean.
To calculate the lift-off time, various factors are taken into account, from the length of the ascending trajectory and the expected thrust performance of each Vega stage to the wind conditions. In case of any delay caused by a technical issue, even if it would only take a short time to fix, the next launch window opportunity will only come around 24 hours later.
The launch, of course, is just the start of operational activities for the flight dynamics team at ESA.
