An overview of the Chandra mission and goals, Chandra's namesake, top 10 facts.
Classroom activities, printable materials, interactive games & more.
Overview of X-ray Astronomy and X-ray sources: black holes to galaxy clusters.
All Chandra images released to the public listed by date & by category
Current Chandra press releases, status reports, interviews & biographies.
A collection of multimedia, illustrations & animations, a glossary, FAQ & more.
A collection of illustrations, animations and video.
Chandra discoveries in an audio/video format.
Q&A: Cosmology

Q:
What if there was an event(source)) picked up by Chandra, detected opposite the center of the universe, 20 billion l/y away, and moving toward us, not expanding or moving away. Could we possibly "see" something that did not originate from "our" universe?

A:
This is counterintuitive, but the universe is actually 156 billion light years wide, according to a NASA study of 2 years ago, because of what happens to light when the universe expands (they may have released a revised number more recently but I didn't see a press release about it). Please see:

http://www.space.com/scienceastronomy/mystery_monday_040524.html There is interesting discussion in the section given under "Impossible? Cornish explains further".

To directly address your question, no event or source can move fast enough to overcome the expansion of the universe that is faster than the speed of light.

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