Astronomy is a study of objects in space, such as planets, stars, galaxies, comets, etc. and their phenomena in space. Astronomy is the oldest science in history, ancient prehistoric tribes have long used astronomy to read constellations, constellations at that time became a clue to predict the future. Astronomical observations in the past were only carried out at night because of the limitations of the tools for observation, therefore the development of astronomy took place very slowly.
Astronomy science or lessons have provided great benefits to the development of natural science, when we study astronomy we can know the movements and distribution of celestial bodies such as galaxies, comets, asteroids, planets, black holes, etc. In addition, we can also know the time count based on the sun or moon circulation. Astronomy science or lessons are also widely used as a benchmark in the calculation and prediction of weather that will occur, this is very useful in shipping, aviation, and other transportation activities.
Apart from that with astronomy science or lessons, we can also find out the process of forming stars, planets, black holes, circular orbits, etc. Researchers in the modern era are now using astronomy to find life on other planets. Considering that the vast universe is not possible there is only one planet that can be inhabited, namely planet earth, researchers are looking for other possible possibilities related to the life of other planets using applied astronomy.
Astronomical science or lessons in its development are divided into specific, more specific branches of science, namely:
1. Practical astronomy
This branch of astronomy studies the ways of observing space objects, what tools to use, and what astronomical methods can be used to obtain answers to such cosmic events.
Astrometry is often referred to as astronomical position, astrometry is a branch of astronomy that observes the geometrical relationships of objects in space, such as calculating distance, inter-planetary position, travel time of rotation and its revolution, etc.
From its name it has been seen that astrophysics is a blend of astronomy and physics, astrophysics is more specifically studying pure celestial bodies physically, including temperature, radiation, the atmosphere layer, the surface layer of the atmosphere.