Aurora effect is known as the aurora borealis or the northern lights. The former term was coined by Galileo in 1619, from the Roman goddess of the dawn and the Greek name for the north wind. The southern counterpart, the aurora australis or the southern lights, has features almost identical to the aurora borealis and changes simultaneously with changes in the northern auroral zone. The Aurora Australis is visible from high southern latitudes in Antarctica, Chile, Argentina, New Zealand, and Australia. A geomagnetic storm causes the auroral ovals (north and south) to expand, and bring the aurora to lower latitudes. The
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