The Galactic Arecibo L-band Feed Array HI (GALFA-HI) Survey has mapped neutral hydrogen in and around our Galaxy with the Arecibo 305 meter telescope. GALFA-HI has an angular resolution of 4' and a channel spacing of 0.184 km/s. It was a commensal survey with the ALFALFA, AGES and GALFACTS surveys. The GALFA-HI Survey DR2 covers ~13,000 sq. deg. and all of the data are public at, https://purcell.ssl.berkeley.edu/.
A 40 degree x 30 degree section of the DR1 data toward RA = 20 deg, Dec = 15 deg
Support for the GALFA-HI survey has been partially provided by the National Science Foundation.
A 20x40 area of sky shown in three different velocity slices (click for high-res version)