The

Bayer designation A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. ...

Xi Sagittarii (ξ Sagittarii) is shared by two

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

s, ξ¹ Sagittarii and ξ² Sagittarii, in the

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the e ...

Sagittarius, separated by 0.46° in the sky. Because they are close to the

ecliptic The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic again ...

, they can be

occulted An occultation is an event that occurs when one object is hidden from the observer by another object that passes between them. The term is often used in astronomy, but can also refer to any situation in which an object in the foreground blocks ...

by the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

and, very rarely, by

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...

s. The last occultation of ξ² Sagittarii by a planet took place on 22 December 1810, when it was occulted by

Venus Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never fa ...

. * ξ¹ Sagittarii * ξ² Sagittarii

Naming

Chinese Chinese can refer to: * Something related to China * Chinese people, people of Chinese nationality, citizenship, and/or ethnicity **''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation ** List of ethnic groups in China, people of va ...

, (), meaning ''

Establishment Establishment may refer to: * The Establishment, a dominant group or elite that controls a polity or an organization * The Establishment (club), a 1960s club in London, England * The Establishment (Pakistan), political terminology for the military ...

'', refers to an asterism consisting of ξ² Sagittarii, ο Sagittarii, π Sagittarii, 43 Sagittarii, ρ¹ Sagittarii, and υ Sagittarii. Consequently, ξ² Sagittarii itself is known as (, en, the First Star of Establishment.)AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 11 日
/ref>

References

{{SIA , astronomical objects Sagittarii, Xi Sagittarius (constellation)