... Radio astronomers at Arecibo Observatory observe a wide variety of phenomena in the Milky Way and in other galaxies. ... Some REU projects are carried out on pre-existing data, and others rely on obtaining new data. ... Deriving a new shape model from existing radar images has been a popular student project in past years, and there are data sets that could be used for this. We are collecting thermal infrared emission data for many of the near-Earth asteroids that are also observed with radar. ...

... 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. ...