Salsa hangs on as onboard power plummets

ESA’s Cluster mission is coming to an end, with the first of the mission’s four satellites, nicknamed Salsa (formally ‘Cluster 2’), scheduled to reenter Earth’s atmosphere on 8 September. As Salsa’s altitude has decreased, it has begun to face a phenomenon known as a ‘perigee power drop.’ This occurs when the satellite is at its closest point to Earth in its orbit, called perigee. Here, the thermal radiation emitted by Earth causes the satellite’s solar arrays to heat up, reducing their...