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SpaceX
Whenever someone proposes to do something that has never been done before, there will always be skeptics. So when I started SpaceX, it was not surprising when people said we wouldn’t succeed. But now that we’ve successfully proven Falcon 1, Falcon 9 and Dragon, there’s been a steady stream of misinformation and doubt expressed about SpaceX’s actual launch costs and prices.NASA Featured Images and Galleries
Flying at an altitude of about 240 miles over the eastern North Atlantic, the Expedition 30 crew aboard the International Space Station photographed this nighttime scene. This view looks ... City lights of Dubai, United Arab Emirates, are featured in this image taken by the Expedition 30 crew aboard the International Space Station.The HET is one of the world's largest optical telescopes, with an effective aperture of 9.2 meters and a 78 square meter, hexagonal mirror array made from 91 segments. Its design is revolutionary. It sits at a fixed elevation angle of 55º, and rotates in azimuth to access 81% of the sky visible from McDonald Observatory (discounting the "high airmass" zone right next to the horizon which telescopes normally avoid). The HET was built for approximately 15-20% of the cost of other 9 meter class telescopes. The tilted Arecibo design, and the cost savings realized throughout the mechanical systems of the HET from the fixed axis concept, broke the standard cost paradigm for large aperture telescopes.

