[1] The 1C catalogue listed about 50 radio sources, detected at 3.7 m with a fixed meridian interferometer.
According to researchers at the Special Astrophysical Observatory [2], most of the sources from 1C were later recognized to be the effect of confusion, i.e. they were not real objects.
The survey was produced using the Long Michelson Interferometer at the Old Rifle Range in Cambridge in 1950.
)−1 x 1025 Note that the position can be specified more accurately for sources of small declination, since the nature of the instrument is such as to make the table errors overstated if the axis is not exactly East-West.
The isotropy of the sources lead the team to conclude that radio stars were either local phenomena, or extragalactic.