- Beta Ophiuchi (Wikipedia)
Beta Ophiuchi or β Ophiuchi, also named Cebalrai /ˌsɛbəlˈreɪ.iː/, is a star in the equatorial constellation of Ophiuchus. The apparent visual magnitude of this star is 2.7, which is readily visible to the naked eye even from urban skies. The distance to this star can be estimated using parallax measurements, yielding a value of 83.4 light-years (25.6 parsecs) from the Sun.
- Tau (Wikipedia)
Tau /ˈtɔː, ˈtaʊ/ (uppercase Τ, lowercase τ, or τ; Greek: ταυ [taf]) is the 19th letter of the Greek alphabet, representing the voiceless dental or alveolar plosive IPA: [t]. In the system of Greek numerals, it has a value of 300.