astrofysikk

Astrofysikk, or astrophysics, is the branch of astronomy that studies the physical properties and processes of astronomical objects and phenomena. It seeks to explain how stars form and evolve, how galaxies and the large-scale structure of the universe develop, and what governs the behavior of extreme objects such as black holes and neutron stars. By applying the laws of physics—nuclear, quantum, thermodynamics, gravity, electromagnetism, and relativity—astrofysikk aims to understand the origin and evolution of the cosmos, from planets to the observable universe.

Key subfields include stellar astrophysics, galactic astrophysics, cosmology, exoplanet science, planetary formation, high-energy astrophysics, astrochemistry, and astroparticle physics. Observational data come from across the electromagnetic spectrum, as well as neutrinos and gravitational waves. Techniques include spectroscopy, photometry, astrometry, timing, and computational simulations (N-body, hydrodynamics).

Major facilities and missions such as the Hubble Space Telescope, the James Webb Space Telescope, the Chandra X-ray Observatory, the Gaia mission, ALMA, and ground-based observatories like the Very Large Telescope and Keck provide data, with future facilities like the Square Kilometre Array expected to expand capabilities. Space-based gravitational wave detectors (LIGO, Virgo, KAGRA) contribute to the study of compact objects and cosmic events.

Astrofysikk overlaps with physics and computer science and drives technological advances in detectors, imaging, data processing, and instrumentation. The field has a long history from early celestial mechanics and spectroscopy to modern cosmology.