Description: Ultraviolet radiation, abbreviated "UV", is electromagnetic radiation made up of elementary waves with wavelengths between 10 and 380 nanometers. These wavelengths lie between X-rays and visible light. Most UV radiation from astronomical objects is absorbed by Earth's atmosphere, so UV astronomy necessarily requires space telescopes, such as the Hubble Space Telescope, or more specialized observatories like GALEX. UV radiation can be used to study hot, young stars, determine the chemical composition of the interstellar medium, study solar activity and our Sun's corona, or explore certain properties of active galactic nuclei.

Related Terms:

• Electromagnetic Radiation
• Visible Spectrum
• Interstellar Medium
• X-ray

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".