Q&A: Chandra Mission
I would like to know more about chandra exposure times versus
visible light images taken with Hubble for Cas A.
Chandra exposure for Cas A: 3000 sec (out of 5000 sec total
observing time, due to technical difficulties during this
checkout phase) Optical exposure: 2400 sec. (A ground based
observation. The Hubble observation didn't turn out to well,
because of the wide field of view and the rapid motions)