Now is the perfect time to look outside in the evening and learn a phrase useful to sky watchers. The phrase is: follow the arc to Arcturus.
First locate the Big Dipper asterism in the northeastern sky. Then draw an imaginary line following the curve in the Dipper’s handle until you come to a bright orange star. This star is Arcturus in the constellation Bootes, known in skylore as the bear guard.
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Arcturus is a giant star with an estimated distance of 37 light-years. It’s special because it’s not moving with the general stream of stars, in the flat disk of the Milky Way galaxy. Instead, Arcturus is cutting perpendicularly through the galaxy’s disk at a tremendous rate of speed … some 150 kilometers per second. Millions of years from now this star will be lost from the view of any future inhabitants of Earth, or at least those who are earthbound and looking with the eye alone.
So that’s how to “follow the arc” to the star Arcturus in the constellation Bootes. Learn how you can drive a spike to the star Spica – and the planet Mars – in the constellation Virgo with the help of tomorrow’s sky chart.
Big and Little Dippers: Noticeable in northern sky
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
Donate: Your support means the world to us
from EarthSky http://ift.tt/1lLgQgD
Now is the perfect time to look outside in the evening and learn a phrase useful to sky watchers. The phrase is: follow the arc to Arcturus.
First locate the Big Dipper asterism in the northeastern sky. Then draw an imaginary line following the curve in the Dipper’s handle until you come to a bright orange star. This star is Arcturus in the constellation Bootes, known in skylore as the bear guard.
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
Arcturus is a giant star with an estimated distance of 37 light-years. It’s special because it’s not moving with the general stream of stars, in the flat disk of the Milky Way galaxy. Instead, Arcturus is cutting perpendicularly through the galaxy’s disk at a tremendous rate of speed … some 150 kilometers per second. Millions of years from now this star will be lost from the view of any future inhabitants of Earth, or at least those who are earthbound and looking with the eye alone.
So that’s how to “follow the arc” to the star Arcturus in the constellation Bootes. Learn how you can drive a spike to the star Spica – and the planet Mars – in the constellation Virgo with the help of tomorrow’s sky chart.
Big and Little Dippers: Noticeable in northern sky
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
Donate: Your support means the world to us
from EarthSky http://ift.tt/1lLgQgD
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