published an orbit using speckle-interferometric data together with Hipparcos observations. Neubauer's 1944 work found a small variation in the radial velocity of Beta Coronae Borealis with a periodicity of 320 days, suggesting the presence of a third, lighter, body in the system. A 1999 study of the system by long-baseline infrared interferometry performed at Palomar Observatory found no evidence for this, and showed that any tertiary companion with this period must have mass 10 Jupiter masses or below. This study also found very weak evidence for the presence of a companion with a shorter, 21-day, period, but the data was insufficient to draw a positive conclusion. The brighter component, Beta Coronae Borealis A, is a rapidly oscillating Ap star, with a period of 16.2 minutes. Of spectral type A5V with a surface temperature of around , it has around 2.09 times the mass of the Sun, 2.63 times its radius and 25.3 times its luminosity. The smaller star is a main sequence star with spectral type F2, a surface temperature of around , around 1.4 times the mass of the Sun, 1.56 times its radius, and between 4 and 5 times its luminosity. The system is around 530 million years old. References Corona Borealis A-type main-sequence stars Binary stars Coronae Borealis, Beta Coronae Borealis, 03 137909 075695 5747 Nusakan BD+29 2670 F-type main-sequence stars Rapidly oscillating Ap stars