| About ROSAT |
ROSAT Home Page | ROSAT Images |
|---|
The PSPC detector entrance window, as well as some of the WFC filters, are
made of polycarbonate materials; when exposed to atomic oxygen,
the predominant species at ROSAT's flight altitudes, such substrates
will be ablated quickly. The problem will be most severe when
the viewing direction of ROSAT coincides with the instantaneous velocity
vector. Therefore the angle between viewing and instantaneous velocity
direction will be kept greater than
. The atomic oxygen problem will be most severe
at those times when the Sun reaches maximum elongation above
or below the orbit plane.