Highlights for the October Night Sky
By Bob Haskins
Do your part and help preserve the dark skies that we are fortunate to have
in Waterville Estates. Turn off all unnecessary outdoor lighting
Go outside tonight and be a stargazer
The Planets: “Evenings on the Ecliptic” The planets all follow an imaginary path in the sky called the ecliptic.
Saturn: The only planet that is visible this month in the evening sky. Look for Saturn low in the SW at dusk until it disappears below the horizon three hours later.
Venus & Mars: Visible at dawn in the eastern sky.
Stars and Constellations:
The bright constellations of summer are being replaced this month by much dimmer ones. Capricornus, Aquarius, and Pisces (see diagram) all represent mythological figures associated with water. The sky in this region is often referred to as the “Great Celestial Sea”.
However, the “Summer Triangle” is still with us this month. It is high in the sky in the early evening but is sinking fast towards the western horizon. The three stars that make up the triangle are “Vega”,the brightest of the three, “Deneb” and “Altair”. Once you see the Summer Triangle you will never forget it.
This month look low in the South (see diagram) and you will see the star Fomalhaut, the “solitary one”. When you are looking in this direction, at this time of the year, you are looking out of our own galaxy. We have to remember that we are located on the edge of our “Milky Way” galaxy and at this time of the year when we look south we are essentially looking out into the vast emptiness of intergalactic space. If you could travel to Fomalhaut and beyond you would soon leave the stars of our galaxy behind.
Also look for the “Great Square of Pegasus”. Look halfway up in the southeast sky and hold your index and little finger in front of you; that will outline the sides of the square. The constellation represents the front end of a winged horse. Pegasus, which according to mythology, was created out of beach sand and sea form and seems to be rising out of the “Great Celestial Sea”. How many stars can you see inside the square? In many locations the answer is zero. Under ideal dark sky conditions you might see a few. Bring binoculars with you. How many stars do you see now?
Two years ago on September 15, 2015 the first gravitational wave was detected which was a spectacular scientific achievement. In 1915 Albert Einstein published his theory on general relativity and his theory predicted that GW existed and they would create ripples in the fabric of space. He said however that we would never be able to detect them because the wave would only be as high as the diameter of the nucleus of a Uranium atom. It took 100 years but science and technology came though once again. Since that historic day in 2015 three more GW have been detected.
Factoid of the Month:
Aristotle was an astronomer in ancient Greece (384-347 BCE). He suggested two reasons why the Earth must be round:
- When a ship came over the horizon you first see the mast and than the main part of the ship.
- During a lunar eclipse the Earth’s shadow was curved as it appeared on the moon. Only a round Earth would produce this effect. Aristotle was way ahead of his time.
Astronomy Websites to explore:
- heavens-above.com (satellites that are passing overhead)
- com (The evening sky map for the month)
- nasa.gov (sign up for alerts for the International Space Station as it passes overhead)