The ROSAT configuration is characterized by two main features.
One is the size of the X-ray telescope (XRT), and the design
for a Delta II launch the other.
The XRT is enclosed by the square shaped central central body
in which that part which serves as optical bench between mirror
assenbly and focal plane instrumentation.
The isostatic mounting via three bearings decouples the telescope
from thermal/mechanical distortions of the satellite structure.
At the front end the telescope carries the two star trackers and
the gyro package, the most important units for attitude measurement,
thus experiencing the same deformations as the telescope and
allowing to meet the stringent accuracy requirements.
The XRT door serves as sunshade during the mission.
On ground is also protects both the telescope and the star trackers
The XRT can be dismounted entirely after removal of the rear central
body panel, which also supports the wide field camera (WFC).
Two compartments on both sides of the central body house almost all
This allows good accessibility and a simple and independent integration.
At the rear part of the central body the Delta II adaption cone is
attached which provides the interface to the second stage of the
Delta II launch vehicle.
The area of the solar generator totals to about 12 m²,
distributed on one fixed central panel anf two hinged deployable panels.
The largely free rear surface allows the dissipation of excess heat
into space and consequently limits the temperature to reasonable levels.
A deployable boom carries the S-band antenna and the magnetometer.
For transportation the satellite can be disassembled into the central
body, including the XRT andsolar panels stowed and into the WFC.
Thus in spite of the size the spacecraft still fits into conventional
A summary of ROSAT system parameters is given in the following table:
Major System Parameter
|dimension (launch configuraion)
||2,38 × 2,13 × 4,50
- sun phase
||700 Mbit pro 21 h|