5: The Sun
- Page ID
- 107997
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Closest star
- Describe how various ancient cultures interpreted the origin of the Sun.
- List different religious representations of the Sun as deities and holidays based on the Sun.
- Review modern cultural events or appearances in media involving the Sun.
- Describe how scientists study distant astronomical objects like the Sun using light.
- Explain the properties of light, also called electromagnetic radiation, and how light can be used to determine the temperature and composition of astronomical objects.
- List and describe the parts of the atom, the nucleus, and the nuclear forces that hold atoms together.
- Explain how spectral lines reveal the composition of gases.
- List and describe the formation and analysis of the three types of spectra used in astronomical observations.
- Describe the advantages and creation of high-resolution and false-color images in astronomical data analysis.
- Describe the various layers of the Sun (photosphere, chromosphere, and corona) and explain how the Sun's composition differs from Earth's.
- Explain the source and nature of solar wind and describe the various ways solar activity manifests itself, including sunspots, flares, coronal mass ejections, and prominences.
- Identify different forms of energy, understand energy conservation and transformation, and explain how matter can be converted into energy through nuclear reactions in the solar interior.
- Describe the structure of the solar interior, explain helioseismology, and discuss how studying solar neutrinos has advanced our understanding energy production in the Sun.
The Sun, our central star in the Solar System, plays a major role in life on Earth. The Sun is about 300,000 times closer than the next closest star, Proxima Centauri. It takes light about 8.3 minutes to travel from the sun to Earth; whereas light from Proxima Centauri takes over four years. Size and temperature-wise, the Sun is an “average” star. The Sun goes through constant changes: energy output, brightness, size; all of which affect Earth. Studying the Sun and how it works allows astronomers to understand other stars. This study of how stars work is called astrophysics. Astronomers also study the Sun’s source of energy: nuclear fusion.
Attributions
This section was adapted from "Our Star, the Sun" in Introduction to Astronomy originally written by Lumen Learning, and published under a Creative Common Attribution License 4.0.
Thumbnail: In this Solar Dynamics Observatory image, the Sun has had no sunspots for almost two weeks (as of Feb. 1, 2018). ("Spotless Days," NASA/GSFC/Solar Dynamics Observatory, Public domain via NASA Image and Video Library)