Space research days in the space station, but this achievement was quickly overshadowed since the crew died on reentry to Earth. Salyut 1 was intentionally deorbited six months into orbit since it prematurely ran out of fuel. Skylab was the first American space station. It was 4 times larger than Salut 1. Skylab was launched in May 19, 1973. It rotated through three crews of three during its operational time. Skylab’s experiments confirmed coronal holes and were able to photograph eight solar flares. From 1986 to 2001, Russian space station Mir served as a permanent microgravity research laboratory in which crews conducted
Artificial satellites in retrograde orbit day over Israel and the surrounding countries, though this optimal Sun-synchronized orbit degrades after several months. They were launched in retrograde orbit so that launch debris would land in the Mediterranean Sea, and not over populated neighboring countries on an eastward flight path. The United States launched two Future Imagery Architecture (FIA) radar satellites into 122° inclined retrograde orbits in 2010 and 2012. The use of a retrograde orbit suggest that these satellites employ SAR techniques. Earth-observing satellites may also be launched into a sun-synchronous orbit, which is slightly retrograde. This is typically done in order to keep a constant