Sentinel-1B, the second spacecraft in the Sentinel-1 family of synthetic aperture radar (SAR) observation satellites, is part of a vast joint research program by ESA and the European Union called Copernicus.

Copernicus aims to provide operational information on land masses, oceans and the Earth’s atmosphere – data that will play a critical role in determining the policies needed to protect our environment and security, and to meet the needs of both consumers and service providers.

The Microscope satellite (Micro-Satellite à traînée Compensée pour l’Observation du Principe d’Equivalence) will test the equivalence principle described by Albert Einstein, with a precision on the order of 10^-15. In space, it is possible to study the relative motion of two bodies in almost perfect and permanent free fall aboard an orbiting satellite, shielded from perturbations encountered on Earth (notably seismic), over the course of several months.

To achieve this, two concentric cylindrical test masses made of different materials – one titanium and one a platinum-rhodium alloy – will be minutely controlled to keep them motionless with respect to the satellite inside independent differential electrostatic accelerometers. If the equivalence principle is verified, the two masses will be subjected to the same control acceleration. If different accelerations have to be applied, the principle will be violated: an event that would shake the foundations of physics.

Fly Your Satellite! is an educational program of the ESA Education and Knowledge Management Office operated in close collaboration with European universities and aimed at complementing academic education.

It is providing university students across Europe with the unique opportunity to gain practical experience in key phases of a challenging, real satellite project: a CubeSat – from integration, test and verification to launch and operations. Through Fly Your Satellite! and other educational projects, ESA acts to inspire, engage and better prepare students to undertake scientific and technological careers, particularly in the space sector. Fly Your Satellite! is part of the newly-established ESA Education and Knowledge Management Office’s program.

As part of the Fly Your Satellite! Program, 3 student-built CubeSats have been selected for launch out of the 6 initial participating teams, and have been working hard to perfect their spacecraft:

• OUFTI-1 from the University of Liege, Belgium, will test a new communications subsystem;
• e-st@r-II from the Polytechnic of Turin, Italy, will demonstrate an attitude determination system using measurements of the Earth’s magnetic field;
• AAUSAT-4 from the University of Aalborg, Denmark, will operate an Automated Identification System (AIS) receiver in order to identify and track the position of ships transiting away from coastal areas.

The Fly Your Satellite! CubeSats will be respectively, the 52nd, 53rd and 54th ESA spacecraft launched by Arianespace.