There’s a very bad bird on the rise.

It’s Aquila the Eagle, one of the 65-plus constellations we see as we peruse our night skies in Butler over the course of the year. According to Greek mythology, Aquila was a favorite pet and an enforcer for Zeus, the king of the gods of Mount Olympus.

Like most of the members in the hierarchy of Greek gods, he wasn’t exactly warm and fuzzy with his supreme power. He was ruthless, and then some.

The ruthless celestial bird is rising in the low eastern sky in the early evening.

The constellation resembles a vertically orientated diamond that outlines Aquila’s wingspan with his tail trailing off to the right. Unfortunately there aren’t any real stars that make up the eagle’s head.

You need to use your full imagination to see that.

The brightest star of Aquila is Altair, found on the left side of the diamond marking Aquila’s heart. Altair is easy to find because it is one of three bright “Summer Triangle” stars presently hanging in the eastern half of the sky.

The Summer Triangle isn’t an official constellation, but is made up of the stars Altair, Vega, and Deneb, the brightest stars in that part of the sky and each the brightest star in its own constellation. Altair is the moderately bright star on the lower right corner of the triangle.

Altair is the 12th-brightest star in our night sky and fairly close to us, at least astronomically.

It’s only about 17 light years away which equates to about 97 trillion miles. Believe it or not, that’s a lot closer than most stars in our heavens.

Because of its proximity astronomers know quite a bit about this star.

Altair is almost 1.5 million miles in diameter, twice as large as our sun, but cranking out a lot more light than our home star, more than 10 times as much.

The most fascinating discovery made about Altair is that it’s quite the spinner, and it has a bulging waistline to prove it.

The Palomar observatory in California discovered that Altair’s diameter is more than 20 percent larger along its equator than from pole to pole.

Altair is spinning on its axis at the dizzying rate of one full rotation in less than 10 hours. By comparison our sun takes more or less an entire month for one rotation.

Altair, like all other stars, is basically a big ball of gas, so the rapid spinning and centrifugal force, the same force you feel on a fast merry-go-round, causes Altair to bulge out big time at its equator.

If you have a small to moderate telescope there’s a nice young cluster of stars you can spy on just off the tail on the right side of Aquila. It’s formally known as Messier Object 11, or M11 for short.

Technically, it’s actually located in a small adjacent constellation called Scutum the Shield. M11 is a beautiful open cluster of almost 3,000 stars that are more than 6,000 light years, or 35 thousand trillion miles, away.

These are young stars only about 220 million years old, which is considered infancy for stellar age. M11 has a nickname, the “Wild Duck Cluster,” because many people see it as a flock of flying ducks. See if you can.

Back to Aquila’s Greek mythological story. Before he became the favorite pet of the king of the gods, Zeus commanded Aquila the Eagle to seek out a “servant” for the gods of Mount Olympus.

Actually, Zeus was demanding a glorified slave. I told you he was a jerk.

He wanted someone who would do all of the housekeeping, wash the windows, mow the lawn, tend the gardens, and also be a highly skilled bartender to the gods.

Aquila soared through the skies for weeks in search of just the right man. He finally spotted a shepherd named Ganymede who was tending a huge flock of sheep.

Aquila studied him for hours and hours and observed how hard this dedicated young shepherd was. Ganymede was definitely the right choice, and Aquila promptly plucked him away from the sheep and whisked him up to Mount Olympus.

It was really tough on Ganymede at first. He greatly missed his family and his sheep, but over time his tears dried and the job grew on him. He became buddies with many of the gods and, being a handsome young man, he attracted the attention of many a beautiful goddess.

Zeus was so pleased with Aquila for his diligence in finding Ganymede that he adopted the faithful eagle as a pet. He began to trust Aquila with noble duties, such as occasionally delivering Zeus’ thunderbolts to Earth.

After a few short years Aquila became Zeus’s chief of staff and personal messenger, as well as his diabolical “hit bird.” Anytime Zeus felt it necessary to enforce or punish, he called on Aquila with his razor sharp beak to carve the violator up.

You don’t mess with Zeus.

The evil eagle would punish mortals and gods alike with great dispatch and without mercy.

After a long life of terrorizing, Aquila finally met his fate while on yet another bloody mission. He accidentally soared into a mountainside on a foggy morning. GPS systems weren’t quite as accurate back in those days.

A greatly distraught Zeus memorialized his faithful hit bird by placing his body among the stars, soaring in the heavens, and reminding all not to mess with the king of the gods.

Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/Paul. He and is author of the book, “Stars, a Month by Month Tour of the Constellations” published by Adventure Publications. It’s available at bookstores and at http://www.adventurepublications.net