LOFAR sharpens the radio view of thousands of galaxies
· BehindLines newsroom
The same patch of sky can tell different stories depending on the light used to observe it. With the European LOFAR network, an international team has produced a particularly detailed radio map of the ELAIS-N1 field. The preprint, submitted on 4 November, combines recent observations with earlier images to bring together 62,916 distinct radio sources.
A catalogue built at several scales
The researchers' abstract describes 200 hours of observations between 115 and 168 megahertz. The field measures 2.5 degrees on each side. The new images distinguish details smaller than one arcsecond and are then combined with less detailed LOFAR data. The catalogue total comes from this combination, rather than the new images alone.
That combination matters for interpretation. Looking for fine details and retaining a wider view are complementary needs. The authors present their calibration method as a step towards deeper and more extensive surveys.
Galaxies seen differently
In its communication on 6 November, Durham University explains that this resolution makes it possible to distinguish structures within distant galaxies, including jets associated with supermassive black holes. Other emissions are connected with star formation. Radio waves also pass through dust that obscures some of these regions in other observations.
Astronomer Leah Morabito contributed to the final catalogue, intended to make the publicly released data easier to use. According to Durham, the work has been accepted in Astronomy & Astrophysics.
For researchers, the value therefore extends beyond a striking image. The catalogue helps them select objects and connect their radio emissions with other observations. The map provides a tool for investigating how galaxies evolve; it does not, on its own, settle every question about their central black holes.