Beta Boötis the ROSAT satellite was used to observe an X-ray flare on Beta Boötis, which released an estimated . This was the first such observation for a low-activity star of this type. The flare may be explained by an as yet unobserved M-type dwarf companion star. Beta Boötis Beta Boötis (β Boötis, abbreviated Beta Boo, β Boo), also named Nekkar, is a star in the northern constellation of Boötes. It has an apparent visual magnitude of 3.5, making it one of the brighter members of the constellation. In the modern constellation, it marks the head of Boötis the herdsman. Based upon
Antinous (constellation) current finds include a celestial globe by the cartographer Caspar Vopel from 1536 that contains Antinous, so Brahe simply measured up the sky according to contemporary traditions and decided to give Antinous a separate table in his star catalogue. In the following modern times, Antinous has been variously considered an asterism within Aquila or as a separate constellation, until the International Astronomical Union discarded it when formalizing the constellations in 1930. Antinous (constellation) Antinous is an obsolete constellation no longer in use by astronomers, having been merged into Aquila, which it bordered to the North. The constellation was created by