Eta Apodis Explained

Eta Apodis, Latinized from η Apodis, is a star in the southern circumpolar constellation Apus. Based upon parallax measurements from the Hipparcos mission, it is approximately 141abbr=offNaNabbr=off from Earth. With an apparent visual magnitude of +4.9, it can be viewed with the naked eye from the southern hemisphere.

Properties

This star has about 1.77 times the mass of the Sun and 2.13 times the Sun's radius. It is radiating 15.5 times the luminosity of the Sun from its outer atmosphere at an effective temperature of 7,860 K. Eta Apodis is a young star with an age of about 250 million years.

The stellar classification of Eta Apodis shows this to be an Am star, which means the spectrum shows chemically peculiarities. In particular, it is an A2-type star showing an excess of the elements chromium and europium. The spectrum displays magnetically-induced features indicating an estimated surface field strength of roughly 360 G. Based upon observations with the Spitzer Space Telescope, this system is emitting an excess of 24 μm infrared radiation. This may be caused by a debris disk of dust orbiting at a distance of more than 31 astronomical units from the star.

In 2023, the star Eta Apodis made history as the first variable star discovery by a Maldivian team, the Space Cat Team, composed of astronomers Gabriel Cristian Neagu and Moosa Samaau. These astronomers harnessed data from the Transiting Exoplanet Survey Satellite (TESS) mission to establish Eta Apodis as an Alpha2 Canum Venaticorum-type variable star. This achievement stands as a noteworthy milestone in the realm of astronomy, underscoring the collaborative expertise of Maldivian astronomers. The star was included in the International Variable Star Index and also contains the internally given name SpaceCat-V1. [1]

Eta Apodis, with its intriguing features and newfound classification as a variable star, remains a focal point of scientific interest, prompting further astronomical investigations and explorations.

Naming

In Chinese caused by adaptation of the European southern hemisphere constellations into the Chinese system, Chinese: 異雀 (Chinese: Yì Què), meaning Exotic Bird, refers to an asterism consisting of η Apodis, ζ Apodis, ι Apodis, β Apodis, γ Apodis, δ1 Apodis, α Apodis and ε Apodis. Consequently, η Apodis itself is known as Chinese: 異雀七 (Chinese: Yì Què qī, English: the Seventh Star of Exotic Bird.)[2]

Notes and References

  1. Web site: VSX : Detail for eta Aps . 2023-10-16 . www.aavso.org.
  2. AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 29 日