OPTI 521 Presentation By Tianquan Su HOW HUBBLE
OPTI 521 Presentation By Tianquan Su HOW HUBBLE SPACE TELESCOPE FAILED
Background Mission Work Launch Fail
Failure Further analysis and computer simulation of the WF/PC images indicated that 0. 5 -waverms wavefront spherical aberration at 547 nm, which could not be eliminated by adjustment.
Where is the problem? Only spherical aberration, no coma: -- probably the primary mirror
About the primary mirror The primary mirror is an aspherical mirror with 2. 4 m diameter. It should have 0. 04 wave rms wavefront error at 632. 8 nm.
Why it was misshaped -- wrong testing Three measures used in the testing of the primary mirror: o Refractive Null Corrector (Rv. NC) -- whose data showed the mirror flaw that match with the telescope error o Reflective Null Corrector (RNC) -- whose data showed the mirror has no flaw o Inverse Null Corrector (test the Rv. NC by stimulate the mirror) -- whose data also showed aberration Funny thing is the manufacturer, Perkin-Elmer Corporation (P-E), trusted the only black sheep of the three
What is RNC? Rv. NC (refractive null corrector) RNC (reflective mull corrector) RNC structure
Testing Chamber
What’s wrong with it?
What’s wrong with RNC The metering rod (with the field cap on)
The initiator of evil Top view of the field cap
Lesson learned -- don’t but your eggs in one basket!
Thank you!
- Slides: 13
