- MARFIK (Lambda Ophiuchi). Double stars are among the prettiest sights the sky has to offer. The best ones, like Albireo and many others, display striking color contrasts that are enhanced by visual proximity effects. But even the white “colorless” ones are attractive, especially if the two members are close together. Those of Marfik (the “elbow” of Ophiuchus), or Lambda Ophiuchi, are so close that they are, however, difficult to separate at the telescope, averaging just a second of arc – a 3600th of a degree – apart.
- Spica (Wikipedia)
Spica is the brightest object in the constellation of Virgo and one of the 20 brightest stars in the night sky. It has the Bayer designation α Virginis, which is Latinised to Alpha Virginis and abbreviated Alpha Vir or α Vir. Analysis of its parallax shows that it is located 250±10 light-years from the Sun. It is a spectroscopic binary star and rotating ellipsoidal variable; a system whose two stars are so close together they are egg-shaped rather than spherical, and can only be separated by their spectra. The primary is a blue giant and a variable star of the Beta Cephei type.