Aurora elders from watching or interpreting the messages of ancestors they believed were transmitted through an aurora. "[[Bulfinch's Mythology]]" relates that in [[Norse mythology]], the armour of the [[Valkyrie|Valkyrior]] "sheds a strange flickering light, which flashes up over the northern skies, making what Men call the 'aurora borealis', or 'Northern Lights' ". There appears to be no evidence in [[Old Norse literature]] to substantiate this assertion. The first Old Norse account of "norðrljós" is found in the Norwegian chronicle "[[Konungs Skuggsjá]]" from AD 1230. The chronicler has heard about this phenomenon from compatriots returning from [[Greenland]], and he gives three possible
R Coronae Borealis the mass of R Coronae Borealis is . The temperature at maximum is reasonably well known at 6,900K and appears to decrease during the fades as the photosphere is obscured by condensing dust. The distance of R Coronae Borealis is not known exactly, but is estimated at 1.4 kiloparsecs from assumptions about its intrinsic brightness. The absolute magnitude of −5 is calculated by comparison with R CrB variables in the Large Magellanic Cloud whose distances are known quite accurately. The luminosity is estimated from helium star models to be and the star has a radius around . The Gaia data