Percival Lowell detail in mid-1896 soon after the Alvan Clark & Sons refracting telescope was installed at his new Flagstaff, Arizona observatory. Lowell observed the planet high in the daytime sky with the telescope's lens stopped down to 3 inches in diameter to reduce the effect of the turbulent daytime atmosphere. Lowell observed spoke-like surface features including a central dark spot, contrary to what was suspected then (and known now): that Venus has no surface features visible from Earth, being covered in an atmosphere that is opaque. It has been noted in a 2003 "Journal for the History of Astronomy" paper and
National Optical Astronomy Observatory shape the System and gain steady, state-of-the-art research capabilities of all apertures for open, merit based science. A future major capability for the US system is an Extremely Large Telescope with diameter up to 30 meters. Two private consortia are currently working on such projects which may be operational before the end of the decade. These are the Thirty Meter Telescope and Giant Magellan Telescope. NOAO is working with both projects in planning for potential future involvement of the broad US community through operational support funding by the NSF. National Optical Astronomy Observatory The National Optical Astronomy Observatory (NOAO) is