V Coronae Borealis (V CrB) is a Mira-type long period variable star and carbon star in the constellation Corona Borealis. Its apparent magnitude varies between 6.9 and 12.6 over a period of 357 days. Based on a period of 357 days, the absolute magnitude of V Coronae Borealis has been calculated to be -4.62. It is estimated to be 880 pc (2,900 ly) from Earth based on parallax, has a luminosity of 5,300 L☉ and a rather cool effective temperature of 1,800 K, these implying a very large radius of about 750 R☉, making V Coronae Borealis one of the largest stars so far discovered. If placed in the center of the Solar System, its size would engulf all rocky planets and reach parts of the asteroid belt.
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![V Coronae Borealis: The visual band light curve of V Coronae Borealis, from AAVSO data[7]](https://upload.wikimedia.org/wikipedia/commons/thumb/4/4e/VCrBLightCurve.png/1280px-VCrBLightCurve.png?utm_source=en.wikipedia.org&utm_campaign=parser&utm_content=thumbnail)
