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Jack Williams is the weather editor for USA Today. Check a FAQ, get weather-homework help or send Jack a message.

Two experts fielded questions during the airing of PBS's "Mysteries of Deep Space" program. Read selected questions and the experts' responses.

Students can ask questions about the solar system, space flight and astronomic phenomena. Consult an archive of past questions and answers.

Team of researchers at the university post previously asked trivia questions and invite visitors to ask just about anything.