3C 303.1
Seyfert 2 galaxy in the constellation Ursa Minor
3C 303.1 is a Seyfert type 2 galaxy located in the constellation of Ursa Minor. The redshift of the object is (z) 0.270 and it was first discovered in the Third Cambridge Catalogue of Radio Sources survey in 1962, where it was identified with a galaxy counterpart in October 1980.
Description
3C 303.1 is a radio galaxy with a strong compact steep spectrum (CSS) source. The host galaxy has a central nucleus that is elongated with two dust lanes obscuring it on both sides. The inner part of the structure is complicated, with the major axis of the isophotes twisted by more than 35°, and has a high surface brightness structure located southeast from the nucleus, implying the galaxy might be in the stages of an ongoing merger. The total ultraviolet luminosity and radio power of the galaxy is estimated to be 8.66 ± 0.66 L☉ and 25.86 Hz, with studies suggesting it underwent a burst of star formation around 10 million years ago.
Radio imaging shows the source has an asymmetric double structure. The structure has two radio lobes located southeast and northwest, of similar morphologies but different flux densities. Two components are present in the source, made up of a highly polarized northern component reaching polarization levels of around 20% and a lowly polarized bright southern component with polarization levels of only 1%. No evidence of a radio core is detected.
The public source identifies “3C 303.1” as seyfert 2 galaxy in the constellation Ursa Minor. This brief keeps that definition visible, then builds a research path around Seyfert, galaxy and constellation.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 3, 2026. The linked authority identifier is Q80674482. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1962 and 1980.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “3C 303.1” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.