... Sextans A: A Seemingly Square Galaxy . ... This image from the Hubble Space Telescope reveals The Cat's Eye Nebula to be one of the most complex planetary nebulae known. ... John Glenn: Discovery Launch . ... At left, the Space Shuttle Discovery waits in darkness on Kennedy Space Center's launch pad 39B. At right, on Thursday October 29, Discovery blasts through a bright afternoon sky returning Senator John Glenn to space over 36 years after he became the first American in orbit. ...