NGC6537 on July 5th, 04:41ut. The Red Spider Nebula (NGC 6537) is a planetary nebula and is located in the Sagittarius constellation. It is about 4,000 light years away. The white dwarf at the center is one of the hottest white dwarfs ever observed. It also produces a hot and very powerful wind at a speed of 300 km/s. Lower image in Ha filter (1hr,10min).