Astronomy, Astrophysics and Cosmology

One of the oldest subjects of study, astronomy seeks to understand everything outside of our world and explain how it got there. Astronomers use telescopes, both on Earth and in space, to study the planets and stars in the night sky - including planets orbiting other stars. Just by looking at things, we can discover a lot about them - from the orbital paths of planets and asteroids to the composition of stars. Looking at everything in the universe is a broad topic, so astronomy is usually broken down into several sections:

Astrometry is the measurement of the position of the objects in the night sky, almost the geography of space. Scientists use all parts of the electromagnetic spectrum, from radio waves to infrared, to make precise measurements of celestial bodies and predict their future movements. Astrometric measurements set the stage for other areas of astronomy, providing vital information about distances and times in the universe.

Galactic and stellar astronomy is the study of galaxies and stars, which make up a large portion of what we see in the sky. Studying the birth, life and death of stars and galaxies tells us about our own galaxy, and our own star - the Sun.

Space physics is concerned with plasma - a state of matter not naturally found on Earth’s surface. Space plasma can be found in the Sun, or in the large magnetic field that surrounds the Earth and is important for radio communications. It can also be found in various commercially available lamps, which you may be familiar with.

Astrophysics looks at understanding the properties of the universe itself; How hot is it? How large is it? What is it made of? This is very closely related to the field of cosmology, which takes these measurements and makes models to explain the origins of the universe.

The field of astronomy has been important since antiquity for keeping track of the seasons and for navigation. In modern times, astronomy is no less important. Observing our complex and beautiful universe inspires scientists to answer the fundamental questions; Why are we here? Are we alone?

From satellites which we rely on for navigation and communication, to bomb detectors in airports, astronomy has played a key role in many technological developments without most of us even knowing.

Articles about astronomy

Subscribe to unanswered questions that interest you by clicking the subscribe lightbulb icon icons in our articles

The Theory of Gravity describes one of the most famous laws of physics, but surprisingly there are still many Things We Don't Know.
Delve deeper into gravity

Gamma-ray bursts are short, powerful blasts of gamma-ray radiation, which originate in deep space.
Delve deeper into gamma-ray bursts

Dark matter is material that does not emit or absorb light (so we cannot see it) but can affect the universe on large scales due to gravitational interactions.
Delve deeper into dark matter

The ultimate fuel of science fiction, antimatter annihilates normal matter on contact and releases immense amounts of energy in the process, making it a somewhat tricky substance to study in a lab.
Delve deeper into antimatter

The Cosmic Microwave Background is a vast energy relic which fills every part of the Universe. We can detect it everywhere, but many questions lie unanswered.
Delve deeper into cosmic microwave background

The Big Bang Theory describes what may have happened during the very early stages of our Universe’s life.
Delve deeper into the big bang

On scales too small to see are weird and wonderful particles. Their bizarre properties make up the world around us, yet we hardly know a thing about them!
Delve deeper into particles

Jupiter is the largest planet in our solar system. It’s been observed since Babylonian times yet we know little about what goes on inside this giant red planet.
Delve deeper into jupiter

The second of the four Jovian planets is known for its magnificent collection of rings; Saturn intrigues us with it’s mysterious nature.
Delve deeper into saturn

Learning about other planetary systems teaches us a lot about our own planet and could potentially lead us to finding extra-terrestrial life!
Delve deeper into planetary systems

The search for alien life catches many people's imagination and has always been a very public branch of science. So with all this investigation, why has our search revealed nothing? Are we truly alone in the Universe?
Delve deeper into extraterrestrial life