Ultraviolet astronomy allows us to study objects that are too hot to emit visible light, such as hot stars, active galactic nuclei, and supernova remnants.

The Galaxy Evolution Explorer (GALEX) is a space telescope specifically designed for ultraviolet astronomy. It was launched in 2003 and has been used to study a wide range of objects, including galaxies, stars, and nebulae.

Stars are the main source of ultraviolet radiation in the universe. Hot stars emit a significant amount of ultraviolet radiation, which can be detected by ultraviolet telescopes.

Ultraviolet astronomy can help answer a wide range of scientific questions, including how stars form and evolve, the nature of black holes and other compact objects, how galaxies interact with each other, and the origin and evolution of the universe.

Ultraviolet astronomy faces several challenges, including the fact that ultraviolet radiation is easily absorbed by the Earth's atmosphere, ultraviolet telescopes are more expensive to build and operate than visible light telescopes, and ultraviolet radiation can damage spacecraft components.

Astronomers can overcome the challenges associated with ultraviolet astronomy by using space telescopes that are placed above the Earth's atmosphere, developing new technologies for ultraviolet telescopes, and using adaptive optics to correct for atmospheric distortions.

Ultraviolet astronomy has led to a number of exciting recent discoveries, including the discovery of the first Earth-sized exoplanet, the detection of water vapor in the atmosphere of a hot Jupiter, and the discovery of a black hole at the center of our galaxy.

The future of ultraviolet astronomy is bright, with the launch of new space telescopes dedicated to ultraviolet astronomy, the development of new technologies for ultraviolet telescopes, and the use of ultraviolet astronomy to study new and unexplored regions of the universe.

The Galaxy Evolution Explorer (GALEX) is the first space telescope dedicated to ultraviolet astronomy. It was launched in 2003 and has been used to study a wide range of objects, including galaxies, stars, and nebulae.

The Hubble Space Telescope (HST) is the largest ultraviolet telescope ever built. It was launched in 1990 and has been used to study a wide range of objects, including galaxies, stars, and planets.

The Kepler Space Telescope discovered the first Earth-sized exoplanet, Kepler-186f, in 2014. Kepler was a space telescope that was launched in 2009 and was used to search for exoplanets.

The Spitzer Space Telescope detected water vapor in the atmosphere of a hot Jupiter, HD 189733b, in 2007. Spitzer was a space telescope that was launched in 2003 and was used to study a wide range of objects, including galaxies, stars, and planets.

The Chandra X-ray Observatory discovered a black hole at the center of our galaxy, Sagittarius A*, in 1999. Chandra is a space telescope that was launched in 1999 and is used to study X-ray sources in the universe.

LUVOIR (Large Ultraviolet Optical Infrared Surveyor) is the next-generation ultraviolet space telescope that is scheduled to be launched in the 2030s. LUVOIR will be able to study a wide range of objects, including galaxies, stars, and planets.

The key science goals of the LUVOIR mission include studying the formation and evolution of galaxies, searching for and characterizing exoplanets, and studying the nature of black holes and other compact objects.