Highlights for the May Night Sky
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 discover the Night Sky
Brought to you by: Bob Haskins
The Planets: Evenings on the “Ecliptic”
Jupiter: “Hail to the King” Jupiter is the highlighted planet of the month. It will be visible all night long. Look for it high in the south at nightfall close to the meridian (the imaginary line in the sky that runs north to south). Jupiter will be shinning at magnitude -2.3 all month (see the comment / factoid section below which explains this). Jupiter is the most rewarding planet to observe with binoculars. Even at 7X it appears as a round disc. But the real show is the four Galilean moons – Io, Europa, Ganymede and Callisto. Dust off your old binoculars and give it a try.
Mars: The “Red Planet” can be seen during the evening twilight in the WNW and sinks below the horizon approximately two hours after the Sun sets. This is the last full month of 2017 that Mars is visible – it will be lost in the solar glare for the summer.
Saturn: The ringed planet, rises in the east at midnight and just before dawn you can spot it in the south.
Venus: If you are up early you can catch Venus rising in the east at dawn. Venus is at its greatest morning brightness for the year.
Stars and Constellations:
The area around WVE is starting to respond to the increasingly direct rays of our yellow star as the Earth leans more into the Sun. The flowers are starting to poke there way through the soil and we gaze in wonder as the Sun is bringing our planet back to life after a cold winter and the stars of winter are slowly sinking in the west.
This month we are featuring the the “Big Dipper”. (see attached diagram below from Chet Raymo’s book, 365 Starry Nights). Look north and you cannot miss it; however, you might have to explain to the children what a dipper is. People in other parts of the world sometimes refer to it as a plow. The Big Dipper is actually an asterism and not a constellation; it is actually part of the constellation “The Great Bear”. An asterism is defined as a group of stars that are not an official constellation. It is however, probably one of the most famous and familiar of all the asterisms / constellations. No other group of stars, except possible for Orion, is easier to recognize. If you follow the handle of the dipper it will point to the bright star “Arcturus” in the east, which is also known as the “Spring Star”. As your vision travels a little further you will see another bright star “Spica” in the south. Remember, “Follow the arc (handle) to Arcturus and you will spy Spica”.
The two stars that make up the front side of the bowl or cup of the Big Dipper are called the pointer stars (see diagram). If you follow them up they will guide you to Polaris, the North Star (see diagram).
A team of astronomers is making a bold forecast: A binary star found in the spring/summer constellation “The Swan” will burst into a nova five years from now. When the two stars crash into one another, they will create a beacon so bright that we will be able to see it with our naked eye. It could become the brightness star in the night-time sky.
Comment / Factoid of the Month:
The scale used to describe brightness is called “apparent magnitude”. It was invented by Hipparchus over 2000 years ago and has stood the test of time. The brightest stars he referred to as first magnitude and the dimmer ones he called sixth magnitude. The scale has been tweaked in recent times. Arcturus has a rating of 0 and Sirius a -1. The more minus the number is the brighter the object.
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 passing overhead)