Glossary term: Galaxy
Description: A galaxy is a system of stars and other material components such as dark matter, gas, and dust that is gravitationally bound, and usually separated from its neighbors by hundreds of thousands of light years. Galaxies come in various different shapes and sizes. The smallest galaxies can have a few thousand stars, while the largest can have tens of trillions. "The Galaxy" or "Galaxy" with a capital letter usually refers to our home galaxy, the Milky Way, which has around 100–400 billion stars.
Related Terms:
- Dark Matter
- Disk Galaxy
- Dust
- Dwarf Galaxy
- Elliptical Galaxy
- Galactic Bulge
- Galactic Center
- Galactic Disk
- Galactic Halo
- Galaxy Cluster
- Gas
- Greenwich Mean Time Zone (GMT)
- Irregular Galaxy
- Milky Way
- Spiral Galaxy
- Star
- Galactic Bar
- Lenticular Galaxy
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Term and definition status: This term and its definition have been approved by a research astronomer and a teacher
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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Credit: NASA, ESA, and S. Beckwith (STScI) and the HUDF Team credit link
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
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Credit: ESO credit link
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
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Credit: ESO/P. Barthel credit link
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
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Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
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astroEDU educational activity (links to astroEDU website) Description: Explore the Milky Way and characteristics of galaxies using glitter drawing.License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Tags: Art , Creativity , Hands-on , Handcraft Age Ranges: 6-8 , 8-10 Education Level: Middle School , Primary Areas of Learning: Fine Art focussed Costs: Medium Cost Group Size: Group Skills: Communicating informationComa Cluster of Galaxies
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