December Moon at Apogee

   Our Moon reaches apogee, (greatest distance from Earth), for this orbit, on Thursday December 5th. At that time the Moon will be at a distance of 31.70 Earth diameters 251,311 miles (404,447 km) from the Earth.

   On the day of the apogee Moon the 9-day old waxing gibbous Moon rises during mid-afternoon and sets later the following morning several hours before sunrise..

   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)

   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to go to bobs-spaces.


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Tales Along the Ecliptic

   Once in a while the planets are arranged such that they are spread across the sky as they look in this graphic. However over time, several days, this arrangement changes as the planets continue moving along their orbits.
   The planets are not lined up in a straight line outward from the Sun but rather are arranged along the ecliptic. The ecliptic is the Earth’s orbital path around the Sun and the respective orbit of each planet is inclined from the ecliptic. And this is one of those times when it is easy to visualize the ecliptic. Click here to read a previous posting about the ecliptic and planet inclination.

   This animated graphic is showing the terrestrial planets as they move along their respective orbits for this month. They are not ‘lined up’ as they appear to be in the above horizon picture.

   This graphic shows the solar system out to Neptune and from this perspective the planets are obviously not in a straight line on December 1st.

   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.


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November Moon at Descending Node

   Yesterday Friday November 29th the Moon crossed the plane of the ecliptic moving south. This is known as the descending node, one of two intersections the Moon’s orbital path (dark green line) has with the ecliptic. For those keeping count this is the 2nd descending node crossing for the Moon this month.

   
   
   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.


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Thin Moon – 2 Days – 2 Conjunctions

   At around sunset Thursday November 28th look toward the western horizon for the 2.5-day old thin waxing crescent Moon to be close to the inner planet Venus, and an outer planet, Jupiter. The Moon will be about 1-2o from Venus and about 6o from Jupiter.
   Too dim to be seen with the naked eye at 8-9th magnitude and about 3o from the Moon is the Dwarf Planet Ceres.
   The planet Saturn is about 12o to the east from the Moon – which is where the Moon will be on the evening of November 29th. The two will be about 1-2o from one another.

   Both of these conjunctions between the Moon and planets are tight enough such that both groupings will easily fit within the field of view of binoculars.


   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.


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A Pair of Conjunctions

   Sunday November 24th there will a photo or viewing opportunity during the twilight hour before the Sun rises and after the sun has set. Starting off the day will be a conjunction involving the very thin waning crescent Moon near the ‘Red Planet’ Mars. The two will be separated by about 3-4o. Lower or to the east is the innermost planet Mercury.
   Then, approximately 12 hours later, the Sun has or is about to set and over the western horizon is a cluster of 3 planets. Close together and separated by about 1-2o are the planets Jupiter and Venus. Higher or to the east is the planet Saturn.
    Both of these conjunctions will look great through binoculars or a wide-field eyepiece on a telescope, and obviously will make for interesting pictures.

   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.


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Venus – Antares Conjunction

   Friday evening November 8th the inner planet Venus will be about 4-5o from the reddish star Antares in Scorpius the Scorpion. Both will easily fit within the field of view of binoculars. Along with Venus there are several planets visible as this graphic shows.

   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.


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Visualize the Ecliptic

Above the Terrestrial Planets this Month

   Once in a while the planets are arranged such that they are spread across the sky. The planets are not lined up in a straight line outward from the Sun but rather are arranged along the ecliptic. The ecliptic is the Earth’s orbital path around the Sun and the respective orbit of each planet is inclined from the ecliptic. And this is one of those times when it is easier to visualize the ecliptic. (see graphics below) Click here to read a previous posting about the ecliptic and planet inclination.

   As the animated graphic is showing the terrestrial planets are not arranged in a straight line. This graphic shows the solar system out to Neptune and from this perspective the planets are obviously not in a straight line.


   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.


Also Follow me and other great resources at Feedspot.