IQ Aurigae

IQ Aurigae is a (most likely) single, variable star in the northern constellation of Auriga. It is visible to the naked eye as a dim, white-hued star with an apparent visual magnitude that fluctuates around 5.38. The star is located at a distance of about 460 light-years from the Sun based on parallax and is drifting further away with a radial velocity of +28.6 km/s.

This is a magnetic Ap star with a stellar classification of A0pSi. It is known as a silicon star, having a strong line of singly ionized silicon, and may also be helium deficient as the lines of helium are weaker than expected. The star is an Alpha2 Canum Venaticorum-type variable, ranging in magnitude from 5.35 down to 5.43 with a rotationally-modulated period of 2.4660 days. It is an X-ray source with a high luminosity of $−0.167$, which may be caused by a combination of shocks in the stellar wind and magnetic reconnection occurring well above the stellar surface. The star has been observed to flare, during which the X-ray emission rose to $3.95$.

IQ Aurigae is 6.3 million years old and is spinning with a projected rotational velocity of 49 km/s, giving it a rotation period of 2.47 days. It has nearly four times the mass of the Sun and 2.6 times the Sun's radius. The star is radiating 263 times the luminosity of the Sun from its active photosphere at an effective temperature of 14,454 K.