Friday morning January 17th, before sunrise, the last quarter Moon will be about 5-6o from the blue-white star Spica in Virgo the Harvest Maiden. However the celestial highlight coming up is further east or lower and closer to the eastern horizon where there are two reddish-colored objects of about the same apparent brightness or magnitude. One object is the planet Mars and the other is the star Antares in Scorpius the Scorpion.
There is an interesting connection between the star Antares and the planet Mars, based on their similar reddish color. There are times like this year when the two are close and part of the mythology surrounding the two suggests that the star was given its name so as to not confuse it with the planet Mars. The name Antares comes from the Greek word translated to ‘Rival of Mars’.
Whenever that was historically Mars was probably known as one of the ‘wandering stars’ from the Greek word ‘planetai’. So with its reddish color, like blood, this ‘wandering star’ came to represent Mars, the ‘G-d of War’. Antares, on the other hand is a red supergiant star with a diameter estimated to be such that if it were at the center of our solar system Antares would fill the solar system out to around the main asteroid belt between Mars and Jupiter.
Northern Hemisphere winter in addition to chilly or cold mornings may sort of warm you, at least in your mind. If you are outside looking at the sky, over the eastern horizon is a large triangular shape of three bright stars. One star each from three different constellations. Deneb in Cygnus the Swan, Vega in Lyra the Harp, and Altair in Aquila the Eagle. This is the asterism (star pattern but not a constellation) the Summer Triangle. There, warmer now?!
So if you are outside checking out the Summer Triangle, or perhaps Mars and nearby Antares and you have an optical aid like binoculars or a lower power wide-field eyepiece in your telescope aim them and your eyes toward the star Altair. In dark enough skies you can make out the stars making up Sagitta the Arrow a few degrees away from Altair.
As Altair is rising and with binoculars move the field of view up to the left until the stars of Sagitta fill the field of view. This small constellation, yes a constellation, could be used as a sort of pointer stars to look a few degrees away for a small open star cluster, Brocchi’s Cluster, or more commonly known as the ‘Coathanger Cluster’.
So if mornings with stars like this don’t warm you up then wait a few months of Earth revolution and these same stars will be showing up in the warmer evening skies of Northern Hemisphere summer and fall.
Friday January 3rd Mars and Uranus will reached their respective orbital positions that have them 180o apart. Mars will be located at approximately 215.3o and Uranus at approximately 35.3o of heliocentric longitude. This called heliocentric opposition.
Tuesday evening December 24th around sunset or after the skies darken look toward the western horizon and you can’t miss noticing the bright celestial object – the inner planet Venus. Also, despite the fact that we are now two seasons away from our summer (Northern Hemisphere), over the western horizon are three stars making up the ‘Summer Triangle’. These three stars each belong to a seperate constellation but together they form an asterism,not a constellation, but a recognizable star shape.
Wednesday morning December 25th look toward the eastern horizon for the ‘Red Planet’ (Mars) to be above the horizon and about 15o from the reddish star Antares in Scorpius the Scorpion. In this graphic Antares is just above the horizon.
Higher above Mars, toward the right or the west, is a the bluish star Spica in Virgo the Harvest Maiden. And higher still but toward the left is another reddish star. This is Arcturus in Bootes the Herdsman.
As this year and decade come to a close I’d like to thank all my readers and the universe in general for allowing me an opportunity to share things celestial.
Have a happy and safe Holiday however you celebrate.
Also Follow me and other great resources at Feedspot.
Monday morning before the Sun rises the 27-day old Moon waning crescent Moon will be about 4-5o from the ‘Red Planet’ Mars. Both will be over the southeastern horizon rising at least 2-3 hours ahead of the Sun.
Our Moon reaches perigee, (closest distance to Earth), for this orbit, on Wednesday December 18th. At that time the Moon will be at a distance of 26.025 Earth diameters, 230,069 miles (370,260 km) from the Earth.
On the day of the perigee Moon the 22-day old waning gibbous Moon will be over the south-southwestern horizon at sunrise local time. The planet Mars is also visible over the southeastern horizon. If your local eastern horizon is low enough then the innermost planet, Mercury, might be seen near the reddish star Antares in Scorpius the Scorpion.
Does our Moon actually go around the Earth as this graphic shows? From our perspective on the Earth the Moon appears to circle around the Earth. However, in reality, the Moon orbits the Sun together with the Earth*
*Click here to read my 2006 Scope on the Sky column “The Real Shape of the Moon’s Orbit”. (PDF)