It is known as the BIG Dipper because close to it there is a smaller, similarly shaped group of stars appropriately know as the Little Dipper. Finding the Big Dipper is very simple. Under good sky conditions, most people can simply look up at the sky and identify it without any guidance, but if you need help finding it, simply look directly North using the compass app of your phone.
Ursa Major is always found in that general direction. On top of its prominent brightness, it also has a bit of a yellowish hue that makes it easier to recognize it. We are going to use Arcturus as our next key point. The following diagram should help if you still have questions. The last step to finding Virgo is to follow that same imaginary line traced in the previous step. After crossing Arcturus as the halfway point, the same line will point to Spica. Spica is the brightest star in Virgo, making it easy to recognize.
Some interpretations only use 9 stars, and others 12, however, the one that better depicts the form of a person, uses 15 stars and is shown in the image below.
Virgo covers 1, square degrees. Most of the constellation's stars are dim, but Virgo's bright blue-white star, Spica, is fairly easy to locate. Stargazers can use the Big Dipper as a guide. Continue the arc to the next bright star, which is Spica. There's even a mnemonic phrase to help you remember: " Follow the arc to Arcturus, then speed on to Spica.
Tied to fertility and agriculture, Virgo appears to stargazers in the Northern Hemisphere during the spring and summer months and to those in the Southern Hemisphere in autumn and winter. Spica , also known as Alpha Virginis, is the brightest star in the constellation.
The cluster forms the largest structure in our region of the universe. The galaxies are bound to each other by their gravity, so they move through space together. The cluster exerts a strong tug on our own galaxy, the Milky Way, and the small band of galaxies that it's bound to, the Local Group.
The Local Group is being pulled toward the Virgo Cluster, and eventually may join it. The largest member of the cluster is M87 , which spans one million light-years and contains one trillion stars or more. It's a type of galaxy known as a giant elliptical. It looks like a fat, fuzzy football. Its core is inhabited by one of the largest black holes yet discovered, a monster about 6. At the other end of the distance scale, Virgo also is home to two of the closest star systems.
But the stars are so puny that they are not visible to the unaided eye. One system, Ross , is less than 11 light-years away; only 10 known star systems are closer. The other, which a pair of stars known as Wolf , is just four light-years farther. Both stars are classified as red dwarfs. They are much less massive than the Sun, so they're only about one ten-thousandth as bright. If any of these stars took the Sun's place, daytime on Earth would be only a few times brighter than a night with a full Moon, and Earth would be an iceball, with no chance for life as we know it.
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