Follow the bow to Arcturus and stab the spike to Spice | Tonight

Follow the bow to Arcturus and stab the spike to Spice. Scouts learn this phrase. Grandparents teach this to children. It was one of the first celestial tools I learned to use in astronomy.

Moreover, these stars can be bright enough to provide a view from a city that is slightly surrounded by light pollution. Finally, Spica serves as a perfect example of a 1st magnitude star, while Arcturus radiates even brighter, shining one size (2 1/2 times) brighter than Spice.

Follow the arch to Arcturus. Find the Big Dipper asterism in the northeast sky in the evening sky this month, maybe around 9 p.m. It is very easy to spot, a large noticeable pattern in the shape of a hole in the northeast. Once you see the Big Dipper, notice that it consists of two parts: a bowl and a handle. Then, with your mind’s eye, extend the natural curve in Dipper’s handle until you reach a bright orange star: follow the arch to Arcturus.

Arcturus is the brightest star in the constellation Shepherd Boötes. This star is known in the sky as the Bear Guard.

Modern astronomers know Arcturus as a giant star with an estimated distance of 37 light-years.

Read more about Arcturus here

Nail the spike to the spike. Once you follow the Big Dipper curve to the star Arcturus, you’re on your way to finding the bright, blue-and-white star Spica. Just extend that same curve on the sky dome.

The peak is the brightest light in the Virgo Virgo, a large, unfortunate constellation. The star and its constellation were sometimes associated with the Greek harvest goddess Ceres. The peak is from the Latin word for ear, and the general connotation is that this stellar name refers to ear of wheat, held by the goddess.

Today we know Spica as a narrow double star. Two stars cannot be distinguished from one point of light by ordinary telescopes. Their dual nature was discovered only by analyzing light from this system using a spectroscope or an instrument that divides light into components. Both stars in the Spica binary system are larger and hotter than our sun. Their diameters are estimated to be 7.8 and 4 times larger than the sun’s diameter and, taken together, they are more than 2000 times brighter than the sun!

Separated by just under 18 million kilometers, Spica’s two stars orbit a common center of gravity in just four days.

Read more about Spitz here

Diagram of the Big Dipper with magenta arrows pointing at Arcturus and Spitz.

On spring evenings in the northern hemisphere, extend the handle of the Great Bear to the arc to Arcturus, stab Spica, and slide into the constellation Corvus the Crow. This is sometimes called an extended bow spring semicircle.

Bottom line: Remember … follow the bow to Arcturus and stab the spike to Spice! Have fun.

EarthSky astronomical kits are perfect for beginners. Order today from the EarthSky store

Donate: Your support means the world to us