Astronomy is more than stars

It+is+common+to+refer+this+branch+of+science+as+the+study+of+the+stars%2C+but+astronomers+study+much+more+than+that.

Photo by David Menidrey on Unsplash

It is common to refer this branch of science as the study of the stars, but astronomers study much more than that.

Marianne Barredo, Staff writer

From our perspective here on Earth, stars are nothing more but twinkling dots that light up the otherwise pitch-black sky of the night. But as both astronomy and history dictate, these celestial bodies are far bigger and brighter than mere dots. The stars we see each night serve plenty of purpose to us down here on the ground observing them, as we’ve put our own meanings and interpretations onto their shining presence.
Out in the night sky, there are groups of stars that are distinctive enough to be identified as a collective. These patterns in the sky form what we call constellations. According to lpi.usra.edu, “most of the constellation names we know came from the ancient Middle Eastern, Greek, and Roman cultures. They identified clusters of stars as gods, goddesses, animals, and objects of their stories.”
Right now, the International Astronomical Union (IAU) lists 88 official ancient and modern constellations. These constellations have boundaries set around them that astronomers recognize as the 88 constellation regions, dividing up the Earth’s celestial sphere and making it easier for us to map out the sky.
It’s important to know that, while these constellations look fixed from our point of view, the stars actually move, both by themselves in the galaxy and to our own naked eyes.
The Earth rotates on an axis— an imaginary line that runs through the North and South Poles. As the Earth rotates, the distant stars in our planet’s background appear to move relative to our location. This is why the North Star, or Polaris, is considered important. While every other star rises or sets at night, Polaris appears to stay fixed due to how the Earth’s axis is pointed almost directly at it.
Windows2universe.org adds that “because of the rotation of the Earth and its orbit around the Sun, we divide the constellations into two groups.” These groups are the circumpolar constellations whose stars, like Polaris, lie above the north and south celestial poles, making them visible all-year round, and the seasonal constellations which can only be viewed at certain times of the year.”
The iconic Big Dipper, which isn’t actually a constellation but rather an asterism, is part of the bigger, circumpolar constellation Ursa Major or the Great Bear. It is one of the most familiar and easiest-to-find star shapes in the northern sky due to how its stars are close to one another and emit about the same brightness, according to space.com. Said to be outlining the Great Bear’s tail and hindquarters, the Big Dipper is made up of seven stars; three that form the “handle” part of its shape and four that make up the “bowl.” Earthsky.org suggests an old saying to remember when trying to find the Big Dipper: spring up and fall down. On spring and summer evenings, the Big Dipper shines highest in the sky, while on autumn and winter evenings, the Big Dipper lurks closest to the horizon.
Northern latitudes are the best places to view the Big Dipper, and this goes the same for the Little Dipper whose stars can be seen relatively close to the other asterism. The slightly dimmer, circumpolar stars of the Little Dipper are part of the constellation Ursa Minor or the Little Bear. Because its stars are fainter, it may be harder to locate the Little Dipper compared to the Big Dipper. Thanks to their proximity however, we can easily use the brighter of the two to guide us.
Earthsky.org provides that the two outer stars of the Big Dipper’s bowl— Merak and Dubhe, are called “The Pointers.” This is because they point to the North Star, Polaris which actually happens to be the last star of the Little Dipper’s “handle.” By imagining a line between these stars, we can locate both the Little Dipper and Polaris from the more visible Big Dipper.
Both the Dippers hovering in the northern hemisphere are circumpolar and therefore can be available for sightseeing every night. But for seasonal constellations resting on the celestial equator, observing the months is the key to spotting them. The famous Orion constellation, for example, is best viewed in the evening skies of January to March and then completely disappears when summertime comes around. According to globeatnight.org, the easiest way to find Orion from the northern hemisphere is to look in the southwest sky. While Orion the Hunter is an entire constellation by itself, locating its asterism which is composed of three bright stars close together in an almost-straight line— Orion’s Belt, can be an easy way to spot him. Its brightest stars Betelgeuse and Rigel serve as Orion’s left shoulder and right foot respectively.
Today, we don’t rely on constellations like early civilizations did. We used to look to the stars for navigation, seeking guidance for travel during the night. With how far human society has reached with technology, we now have tools like advanced compasses and GPS to aid us in determining our whereabouts more efficiently and accurately, but this does not mean that those distant bodies of light no longer hold purpose for us. After all, our most important star— the Sun, gives us life and is responsible for the time of day.
The stars we see at night likewise provide their own use for us, as astronomers use constellations in tracking artificial satellites as well as assisting navigators to locate certain stars. It’s a marvel how we can find shapes in these faraway objects and give them relevant use, no matter how distant or small in our eyes they are.

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