This week will likely provide you with your very last opportunities to get a glimpse of a big German satellite, first put into orbit back in June 1990 and which has been dormant since February 1999.
The decommissioned German X-ray space observatory, called the Roentgen Satellite or ROSAT, will likely re-enter Earth’s atmosphere sometime between Oct. 22 and 24. ROSAT is currently moving around the Earth in a nearly circular orbit at an altitude of about 145 miles (236 kilometers) at an inclination of 53 degrees, which means that it is visible from virtually all inhabited regions on Earth.
Satellites become visible only when they are in sunlight and the observer is in deep twilight or darkness. This usually means shortly after dusk or before dawn. On any clear evening within a couple of hours of local sunset and with no optical aid, you can usually spot several orbiting Earth satellites moving with a steady speed across the sky like moving stars. [Photos: Germany's ROSAT Satellite Falling to Earth]
Last Chance to See Doomed German Satellite in Night Sky
