Glossary term: Bintang kelas A
Description: Bintang dengan kelas spektrum "A". Para astronom mengidentifikasi bintang kelas A dari kehadiran garis serapan terkuat hidrogen dalam spektrumnya. Bintang kelas A memiliki temperatur (efektif) antara sekitar 7400 kelvin (K) dan 10.000 K. Dibandingkan dengan bintang lainnya, bintang kelas A tampak putih atau putih kebiruan jika dilihat dengan mata, Warnanya bisa tampak berbeda jika dipengaruhi oleh efek pemerahan antarbintang atau atmosfer. Sirius, bintang paling terang di langit malam, dan Vega, bintang yang menjadi patokan untuk mengukur kecerlangan bintang-bintang lain dalam skala magnitudo semu, adalah bintang kelas A.
Related Terms:
See this term in other languages
Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher The translation of this term and its definition is still awaiting approval
The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".
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In Other Languages
- Arab: نجوم النسق الأساسي نوع A
- Bengali: "A"-টাইপ নক্ষত্র
- Jerman: A-Stern
- Inggris: A-type Star
- Spanyol: Estrella tipo A
- Perancis: Étoile de type A
- Ibrani: כוכב מסוג A
- Italia: Stella di tipo A
- Jepang: A型星 (external link)
- Portugis Brazil: Estrela de tipo A
- Portugis: Estrela de classe A
- Tiongkok Sederhana: A型星
- Tiongkok Tradisionil: A型星
Related Media
Sirius A with his faint white dwarf companion Sirius B
Caption: This Hubble Space Telescope image highlights Sirius, the brightest star in Earth’s night sky, appearing as an intensely luminous object at the center with prominent cross-shaped diffraction spikes. These spikes, along with the saturated glow around the main star, are caused by the Sirius' light being spread out by the telescope and camera used to make this image. Slightly below and to the left of the main star, a tiny point of light marks Sirius B, a much dimmer object captured thanks to Hubble’s high sensitivity.
Sirius A is an A-type star, known for its high surface temperature and strong white-blue light, while Sirius B is a compact white dwarf, the dense remnant of a star that has exhausted its nuclear fuel. Together, they form a well-known Binary star system located about 8.6 light-years from Earth.
Sirius B was originally a higher mass and brighter star that burned through its hydrogen fuel more quickly than Sirius A. This led to Sirius B evolving into a red giant and eventually ending its life as a planetary nebula, leaving only the remains of its core as a white dwarf orbiting Sirius A.
Credit: NASA, ESA, H. Bond (STScI), and M. Barstow (University of Leicester)
credit link
License: CC-BY-4.0 Creative Commons Atribusi 4.0 Internasional (CC BY 4.0) icons
Related Diagrams
Spectrum of an A-type star
Caption: The spectrum of the A-type star BD-11 1212. The colour of the line between 400 nm and 700 nm roughly corresponds to the colour the human eye would see light of that wavelength. Below 400 nm and above 700 nm, where the human eye can see little to no light, the lines are coloured blue and red respectively.
The black lines show spectral absorption lines caused by atoms and ions of different elements in the star’s atmosphere. These atoms and ions absorb at specific wavelengths, causing sharp, dark lines in the spectra. How strong these lines are depends on the temperature of the star’s atmosphere. Two stars made from the same mix of elements could have spectra with vastly different sets of lines in their spectra if they have different temperatures in their atmospheres. Lines from hydrogen atoms dominate the spectra of A-type stars and are strongest at this spectral type.
Credit: IAU OAE/SDSS/Niall Deacon
License: CC-BY-4.0 Creative Commons Atribusi 4.0 Internasional (CC BY 4.0) icons
