What is Astronomy and What is Astrophysics When Understood Laid Bare?

As soon as you have thought about the shining stars, planets, or galaxies, you are already in contact with the words astronomy and astrophysics. In fact, it is common to treat these terms as if they were all the same when they really refer to different approaches when studying the universe. Let’s try and break that down in simpler terms and see just how these two more than interesting fields differ.

Astronomy: What Is It?

Astronomy is an old science that goes back thousands of years ago to when the human eye first turned skyward to look. It is simply the watching and recording of objects in the sky – stars, planets, comets, galaxies – and the observation of their motion and behavior. Imagine astronomers as the explorers of the universe trying to map it.

Important Features of Astronomy:

• Observation-Based: An astronomer studies what a telescope (ground- or space-based) should collect about a celestial body.
• Descriptive Science: They count what they see-positional, brightness, movement–and make itemized lists of stars, galaxies, and so on.
• Tools of the Trade: Telescopes, Spectroscopes and imaging instruments are tools that the astronomer must have.

Take, for example, when an astronomer might study a distant star’s brightness, temperature, and position in time. His job might be like an item-by-item inventory of the universe.

What is Astrophysics?

It goes further in the direction of applying the laws of chemistry and physics into explaining what the astronomers have observed-the behavior of celestial bodies. Celestial phenomena has a lot to do with things and how they happened. “What” entails astronomy, while “how” and “why” refer to astrophysics.

Major Features of Astrophysics:

• It is mainly theoretical science: Black holes, supernovae, or galaxy evolution, for example, are phenomena which an astrophysicist will study using mathematical models and simulations.
• It is physics-based: The study of celestial bodies in terms of gravity (best known), nuclear fusion in stars, or behavior of dark matter.
• Great Questions: These are among the many questions an Astrophysicist would answer: “What is dark energy?” or “How do stars evolve?”.

For example, an astronomer would see a spectrum of light from a star in order to calculate the temperature of that star, while an astrophysicist would take that and simulate how nuclear reactions power that star.