In 1984, a Delta 3920 rocket blasted off from Vandenberg airbase in California carrying two satellites destined to make a difference– NASA’s Landsat 5 and University of Surrey’s UoSAT-2.
Almost 30 years on, these satellites are far from being forgotten.
, the workhorse of the Landsat programme, was officially decommissioned this month, after an impressive 29 years in operation. It has imaged almost every major event in the last 3 decades and mapped the vast changes Earth has experienced over that time– not least the affect of a growing population (from 5 billion to 7 billion since it was launched) on our planet.
Against expectations, Landsat 5 lasted long enough to prevent what seemed like an inevitable data gap– and held out until the Landsat Data Continuity Mission (LDCM
), or Landsat 8, took over this year. All this from a satellite that was only originally intended as a backup for Landsat 4, which itself lasted almost 19 years.
, which is still broadcasting now, has been operational for over 29 years– longer than some SSTL staff have been alive! UoSAT-2, as one of Surrey’s inaugural satellites, has always held a special significance and has remained a constant in SSTL’s evolution from University offshoot to the World-leading small satellite manufacturer. It was one of the first satellites to prove that microprocessors and memory chips, which became readily available, mass produced and cheaper in the early 80s as part of the microcomputer revolution, could be used to build small, cost-effective and capable satellites. The idea to take advantage of new commercially available technology, instead of designing everything from scratch, was virtually unheard of at the time.
UoSAT-2 provided a novel communication system for the 1988 Ski-trek arctic expedition
and thousands tuned in to hear its broadcasts, created by its speech synthesiser. Since, the satellite has been enthusiastically tracked by AMSAT members and organisations for educational and recreational purposes.
The lifespan of these satellites is testament to the engineers who worked on the missions and the ground station staff who have carefully operated them over the years. Both satellites were part of a lasting legacy– the Landsat programme continues to provide valuable Earth observation data and UoSAT-2 led the way for small satellites and also successful collaboration between the University of Surrey and SSTL that is still going strong today. These satellites’ heyday may be over, but their longevity is a sign of what satellites can achieve and how they can make a difference to our lives on Earth.