Taevaobjektide

Taevaobjektide (Estonian for celestial objects) are natural bodies and phenomena found in outer space that can be observed from Earth or with spacecraft. They range from solar-system bodies to distant extragalactic objects, and even transient events such as supernovae. The study of taevaobjektide seeks to understand their origin, structure, and evolution, as well as the physical processes that govern the universe.

Classification: Within the solar system: planets, dwarf planets, moons, asteroids, comets, and meteoroids. In interplanetary space and beyond: stars, star clusters, nebulae, galaxies, quasars, and black holes. Observationally, objects are described by size, composition, luminosity, distance, and motion, and may be observed across the electromagnetic spectrum (visible, infrared, radio, etc.).

Observation and methods: Telescopes and detectors collect light and other radiation. Spectroscopy reveals composition and motion; photometry measures brightness. Distances are estimated by parallax for nearby objects, standard candles for distant objects, and redshift for galaxies. Radar is used for some solar-system bodies, while spacecraft provide direct measurements for a few.

Significance: Taevaobjektide underpin models of planetary formation, stellar evolution, and cosmology. They offer targets for exploration and are accessible to amateur observers who study the Moon, planets, comets, and variable stars.