What is Astrophysics?

Astrophysics is a branch of astronomy that analyzes the properties and interactions of cosmological objects based on known physical law. The term is slightly misleading, as anyone who goes into astronomy nowadays must be proficient in physics. It can be said that the field of astrophysics is very similar to the fields of astronomy and cosmology.

Astrophysics can be broken down into observational and theoretical astrophysics. There is no such thing as experimental astrophysics because the scales and objects being observed are far too large or far away to experiment on with modern technology. Because light takes time to travel to us on Earth, the most distant regions of the universe are actually windows into the ancient universe, when the universe was far denser and more energetic. Because astrophysics sometimes deals with theories of the early, compact universe, it can overlap strongly with particle physics, which provides predictions of how matter would behave in the ancient universe.

Astrophysicists are known for studying such phenomena as black holes, galaxies, superclusters, neutron stars, quasars, the Big Bang, dark matter and energy, cosmic strings, stellar evolution, the cosmic microwave background radiation, and many others. The cosmos is a good arena for studying pure physics because on such large scales, the particular type of element making up objects becomes less significant, and more general variables such as mass and velocity take primacy. Sometimes astrophysics is called "the study of the very large and the very small."

Astrophysicists have contributed many important insights to our understanding of the universe we live in. They have predicted the likely age of the universe, the size of the observable universe, how long our sun will last before it exhausts its nuclear fuel, the commonness of black holes and other exotic celestial bodies, what the universe looked like billions of years ago, the average temperature of interstellar or intergalactic space, the shapes of galaxies, and the way that matter is distributed across the observable universe. Astrophysics is a useful branch of science that always continues to evolve and produce fascinating new insights into the structure of our universe.