ESA | Space Science | 16 July 2010
ESA’s pioneering Cluster mission is celebrating its 10th anniversary. During the past decade, Cluster’s four satellites have provided extraordinary insights into the largely invisible interaction between the Sun and Earth.
Cluster’s four satellites, Rumba, Samba, Salsa, and Tango, fly in formation around Earth to provide a 3D picture of how the continuous ‘solar wind’ of charged particles or plasma from the Sun affects our near-Earth space environment and its protective ‘magnetic bubble, known as the magnetosphere.
... The observations have revealed a dramatic realm of invisible violence. Cluster has investigated how the solar wind penetrates near-Earth space and discovered that, under certain circumstances, magnetic whirlpools larger than the entire Earth bore into our magnetosphere, injecting their venomous particles.
When these solar wind particles reach Earth’s atmosphere, they trigger the sublime glow of the northern and southern auroras. Here too, Cluster has been a revelation.
Cluster has confirmed that black auroras, strange electrical phenomenon that generate dark, empty regions within the Northern and Southern Lights, are a kind of 'anti-aurora', sucking electrons from the ionosphere.
Undoubtedly one of the major highlights of the mission has been the first 3D map of the heart of a ubiquitous magnetic process called reconnection.
