NATIONAL ASTRONOMY AND IONOSPHERE CENTER . ... Astronomy . ... Visitor Center . ... Kick-Off Ceremony of the Arecibo Observatory 50th Anniversary . ... ASTEROID 2005 YU55 . ... ASTEROID FLYBY : NASA radars are monitoring 2005 YU55, an asteroid the size of an aircraft carrier, as it heads for a Nov. 8th flyby of the Earth-Moon system. ... Astronomers used the planetary radar system at the Arecibo Observatory radio telescope to spot the asteroid, called 2005 YU55, over four days starting on April 19 . ...
... 2.3 Data acquisition Spectra generated by the Multibeam correlator contain the usual structure seen in spectra from other H i instruments: a bandpass spectrum which is the sum of the sky , ground and receiver temperatures multiplied by the product of the filters in the receiver chain; superimposed on this is a noise ... Note also that sources extended much beyond ,40 arcmin can be imaged poorly in HIPASS images because of the bandpass sidelobe effect described in Section 3.3. ...