The night sky remains one of the great enigmas to humankind. People have been fascinated with the stars and skey since their inception. Many ancient civilizations loved the stars and were excellent at studying their movement. Astronomy was one of the first scientific fields to develop and contribute to scientific knowledge.
In many places, light pollution has made it more difficult to connect with the stars in populated areas. But today, we know more about the heavens than at any other point in history. It is never too late to cultivate a deep appreciation for the starry sky, and with a little effort, anyone can delight in the spectacle nature offers each night.
What is Astronomy?
Put simply, astronomy is the study of the universe at the largest scales. At first, human astronomers stargazing at night did not fully understand the lights they were looking at. But over time, as modern science progressed, astronomers began to realize the true nature of the stars. They learned that many of the stars in the night sky were other stars just like the Sun. Some of the bright objects are other planets and even entire galaxies, like the Milky Way.
Today, scientists know that the observable universe contains perhaps two trillion galaxies, each containing on average perhaps one hundred billion stars! "Huge" doesn't even begin to capture the vastness of the cosmos. As more has been learned about the universe, all sorts of other strange things have been uncovered: black holes, colliding galaxies, and humongous clouds of dust and gas giving birth to new stars. At each step, astronomers added these new, strange things to their field of study, ultimately arriving at the expansive modern conception of astronomy.
When astronomy first began, one of the central organizing practices was identifying "constellations" among the stars. A constellation is an imagined figure that is projected onto a pattern of stars. People would see a collection of stars that reminded them of some Earthly object, like a person, an animal, or a tool, and name the collection of stars for that object.
It is important to keep in mind that the constellation is the way the stars appear to humans here on Earth. But the different stars that make up a constellation may not really be near each other in physical space. For this reason, star constellations are not a focal point of study for astronomers today. However, they are still a central part of sky watching, because they help astronomers find their way around the night sky. By learning to recognize the constellations, professional and amateur astronomers can orient themselves at a glance, and this can be useful in finding objects of interest. Learning and recognizing constellations also offers its own delights.
Some of the most widely recognizable constellations include the big and little dippers, and the hunter, Orion. But there are dozens of less widely-known constellations. Many of these are best viewed away from bright city lights, though others can manage to shine through the city lights.
Today, it is easier than ever to get started learning to find constellations, since there are a number of smartphone apps—such as SkyView and Star Map—that are designed to help guide new sky watchers.
What Can You View in the Night Sky?
The night sky is packed with unending sources of awe and wonder for those who are open to it. From Earth, the most familiar and luminous object is the Moon. This can easily be seen with the naked eye, and learning to track its rhythms is a good way to begin studying heavenly bodies.
Using just the naked eye, it is also possible to spot countless stars and the constellations they make up. In certain parts of the world (typically in more southern regions), sky watchers are treated to the breathtaking sight of the Milky Way galaxy. With a little practice and study, it is also possible to recognize some of the other planets of our solar system—such as Venus and Mars.
But there are limitations on what human eyes can see in the sky, since they function best at short-range distances. That is why professional astronomers build huge observing towers, and have even sent out telescopes into space. Those aren't feasible for most amateurs, but to dedicated enthusiasts, naked eye observations aren't enough, and many seek to amplify their viewing powers by purchasing a home telescope. These range from very affordable to very expensive, and they expand what can be seen in the night sky. Many home telescopes offer spectacular views of nearby objects like the Moon, Venus, and Mars. Stronger telescopes can even enable users to see the moons of Jupiter, the rings of Saturn, and the outlines of distant galaxies and nebulae. But with or without a telescope, the most important thing is to be open to setting aside a little time at night to study and take in what nature has to offer.