The Web Window to the Invisible Universe

We have produced a new map of the radio sky observed at a frequency of 4850 MHz. This map portrays how the sky would appear to the aided radio eye. Click on the image below to download a higher resolution JPEG (1.3MB).

In the map, the central band of bright emission originates from the plane of our galaxy. Along the plane are clouds of ionised hydrogren (HII regions) associated with stellar birth. You can also see galactic spurs, loops and shells of expanding gas resulting from supernovae, the remnants of stars past.

The numerous star-like objects distributed evenly throughout the image are distant sources of intense radio emission known as radio galaxies and quasars. Among these are some of the most luminous and distant objects in the known universe.

Image Details

The above map was produced by combining data from the NRAO 1987 Green Bank (87GB) and the Parkes-MIT-NRAO (PMN) radio surveys. An Aitoff projection was used to map the 87GB and PMN data over the whole sky. The Aitoff system has the "equal area" property, meaning that a unit area anywhere on the sky projects to a constant area on the map. The image was produced using the Astronomical Image Processing System (AIPS).

Only the central third of the projection is displayed above. Galactic longitude increases from the map centre (l=0 & b=0 deg) to the left of the image and the North Galactic Pole is off the top. When I find some spare time I will include the remaining images towards the north and south galactic poles. The arc-like gap in the image is due to missing data from the PMN Zenith survey, this data will be added when it becomes available. The circular gaps around the north and south celestial poles were not observed by the Green Bank and PMN surveys.

Other Radio Survey Web Sites

The NRAO VLA Sky Survey (NVSS) - The NVSS project will survey 82% of the sky at 1.4GHz by the end of 1996 using the NRAO Very Large Array (VLA).

Faint Images of the Radio Sky at Twenty-centimeters (FIRST) - The FIRST project will produce radio images for 10,000 square degrees of the sky around the North Galactic Cap using the NRAO VLA.

Westerbork Northern Sky Survey (WENSS) - The WENSS will survey a large part of the northern sky (b > 30 degrees) at a wavelength of 92cm using the Westerbork Synthesis Radio Telescope.

The Leiden/Dwingeloo HI Survey - A northern sky HI (neutral hydrogen/1420MHz) survey of our galaxy using the 25m telescope of the Netherlands Foundation for Research in Astronomy.

The Parkes 21cm Multibeam Survey - An HI survey of the southern sky using the upgraded Parkes 64m radio telescope.

The Sydney University Molonglo Sky Survey (SUMSS) - is a deep radio survey of the entire sky south of declination -30 degrees at a frequency of 843 MHz.

The Canadian Galactic Plane Survey (CGPS) is a survey which will cover Galactic longitudes from l=74.2 to 147.3 degrees and latitudes from b=-3.6 to +5.6 degrees at wavelengths of 1420 and 408 MHz.

The First Galactic Plane survey at 8.35 and 14.35 GHz - Observations of the galactic plane ( |b| < 5 degree, l = -15 degree to 255 degree) at 8.35 and 14.35 GHz performed by the NRAO/NASA Green Bank Earth Station.


The AITOFF maps were produced by Niven Tasker (Macquarie University/ATNF). The PMN and 87GB survey map data were produced by Jim Condon (NRAO) and Niven Tasker (Macquarie University/ATNF). The original surveys were chiefly the work of Jim Condon (NRAO), Mark Griffith (MIT) and Alan Wright (ATNF).