the Struve–Sahade effect. This is an anomalous change in the strength of the spectral lines over the course of an orbit, where the lines become weaker as the star is moving away from the observer. It may be caused by a strong stellar wind from the primary scattering the light from secondary when it is receding. This star is smaller than the primary, with about 7 times the mass of the Sun and 3.6 times the Sun's radius. Its stellar classification is B2 V, making this a main-sequence star. In culture Both American ships USS Spica (AK-16) and USNS Spica (T-AFS-9) were named after this star while USS Azimech (AK-124), a Crater-class cargo ship, was given one of the star's medieval names. Both a rocket and crew capsule designed and under development by Copenhagen Suborbitals, a crowd-funded space program, is named Spica. Spica aims to make Denmark the first country to launch its own astronaut to space after Russia, the US and China. In his Three Books of Occult Philosophy, Cornelius Agrippa attributes Spica's kabbalistic symbol to Hermes Trismegistus. See also Lists of astronomical objects References B-type main-sequence stars B-type subgiants B-type giants Beta Cephei variables Binary stars Rotating ellipsoidal variables Virgo (constellation) Virginis, Alpha 5056 Durchmusterung objects Virginis, 067 116658 065474 Stars with proper names