Astronomers study the universe in order to better understand what it is comprised of and how celestial bodies and energy function within it. Astronomers seek to understand the origins, evolution, composition, motions, relative positions, size and movements of celestial bodies, including planets and their satellites, comets and meteors, stars and interstellar matter, galaxies and clusters of galaxies, black holes and magnetic fields, etc.

How did matter and energy in the universe ever come to be? How is the universe structured? What energy forces exist in the universe and how do they function? Will the universe continue to expand forever? How are celestial bodies born? How do they function? How do they evolve? How do they die? Do planets similar to earth exist in the universe? What questions remain to be asked about the universe?

Astronomers gather information about celestial bodies and energy through direct observation and indirect measurements. Developing methods for gathering information about the universe is a key ongoing focus of astronomers’ work. For example, they use telescopes, as well as images taken from balloons and satellites. They gather information about radiation of bodies in the universe through the electromagnetic spectrum, including radio waves, ultraviolet and infra-red radiation, X-rays and gamma rays. Telescopes placed on orbiting satellites gather information about radiation blocked by the atmosphere. Astronomers rely on computers with image processing software that notes the power and shape of light. They also use the interferometer, a series of telescopes that collectively have tremendous power.

Astronomers make judgments about the universe and how it functions. Using the instruments they design and continually seek to refine, they make judgments about suns, stars, satellites, moons, nebulae and galaxies, black holes, magnetic fields, gas clouds, comets, etc. They make judgments about the distances, brightness, and composition of celestial bodies and their temperature, radiation, size, and color. From a practical perspective, astronomers make judgments that include making astronomical tables for air and sea navigation, and determining the correct time.

The universe is the most fundamental concept in astronomy. The universe is the total of all bodies and energy in the cosmos that function as a harmonious and orderly system. Other important concepts in astronomy include: gravity, electromagnetism, nuclear forces (strong and weak), and quantum theory.

1) There are laws governing the universe, though we don’t yet know them all;

2) The universe is largely unexplored and at present unexplained;

3) We need to develop better instruments of observation and measurement to understand the universe; and

4) Judgments in astronomy are limited by the observational instruments and research methods currently available.

One important implication of astronomy is that, as we improve our understanding of the universe, based on scientific observations and conclusions, we improve our understanding of life as an organic process, and we therefore rely less on myth to explain the universe. Furthermore, advances in astronomy help us see the earth as a miniscule body within a vast, expanding universe, rather than the earth (and therefore humans) as the center of the universe.

Astronomers look at the universe, and see a vast system of systems and a hugely unexplored space waiting to be discovered and understood.