October Moon at Ascending Node, and at Perigee

   Wednesday October 31st the 22-day old last quarter Moon will be crossing the ecliptic moving north. This is known as the ascending node, one of two intersections the Moon’s orbital path has with the ecliptic. (see animated graphic below)
   Also on that same day, Wednesday October 31st, the last quarter Moon reaches perigee, (closest distance from Earth). At that time the Moon will more or less be at a distance of 29.025 Earth diameters, (230,032 miles 370,201 km), from the Earth.


On the day of perigee and ascending node the first quarter Moon rises at around midnight and is only a few degrees away from the open star cluster M-44, the Beehive Cluster.

   
   
   

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.

August Perigee Moon at Ascending Node, and a Partial Solar Eclipse

   Friday August 10th the 28.5 day old waning crescent Moon will be crossing the plane of the ecliptic moving north relative to the ecliptic. This is known as the ascending node, one of two intersections the Moon’s orbital path has with the ecliptic. The ecliptic is actually the Earth’s orbit and the Moon’s orbit is inclined about 6o from the ecliptic. So there are two node intersections, the ascending and descending nodes.

   Does our Moon actually go around the Earth as many graphics show? 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)

Read this very informative article about the Earth-Moon system and their orbital motions, written by Joe Hanson. “Do We Orbit the Moon?”

Perigee Moon
   Our Moon reaches perigee, (closest distance to Earth), for this orbit on Friday August 10th. At that time the Moon will be at a distance of 28.07 Earth diameters (358,100 km or 222,513 miles) from the Earth. The Moon will also be 28.5 days old, and only 15.8 hours from new Moon Phase.
    When the time of perigee is close to a node crossing there will be either a lunar or solar eclipse. In this case less then 24 hours after the node crossing there will be a partial solar eclipse. This solar eclipse is only visible from Arctic, Greenland and parts of Asia.

   
   
   

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.

Circumstances for a Solar Eclipse


   Friday July 13th and Saturday the 14th circumstances are such that there will be a partial solar eclipse that will be best viewed from along the northern coast of Antarctica. (hey! every Antarctic coast is a northern coast!!
Specifically the partial solar eclipse will be visible at around 129o E near the Claire Coast.

   Circumstances for a solar eclipse, like for a lunar eclipse, require the Moon to be at either its ascending node or its descending node and be at or close to either new or full Moon phase. A node crossing occurs when the Moon with an orbit tilted 6o from the ecliptic (the Earth’s orbit) intersects the ecliptic.


   The Moon has an elliptically shaped orbit so if the timing for lunar apogee (furthest from Earth) or perigee (closest to the Earth) happens around a new Moon at a node crossing then the apparent size of the Moon will be anywhere from smaller to larger than the Sun’s apparent size. Smaller means a longer eclipse including the length of totality.


   
   
   However the bottom line is the timing between the node crossing and new Moon. This time the Moon crosses the ecliptic moving north, ascending node, approximately 24 hours after new Moon phase setting up a partial solar eclipse.

So what are the circumstances?
Times are in Universal Time (CDT = UT-5)
   July 13th
   1:48 UT – Partial Solar Eclipse Begins
   2:48 UT – New Moon — Partial Solar Eclipse
   3:01 UT – Mid-Eclipse (maximum Sun covered)
   4:13 UT – Partial Solar Eclipse Ends
   8:27 UT – Moon at Perigee – 357, 432 km (222,098 miles)
   July 14th
   2:52 UT – Moon at Ascending Node

   
   
   

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.

June Perigee Moon

   Our Moon reaches perigee, (closest distance from Earth), for this orbit on Thursday June 14th. At that time the Moon will be at a distance of 28.18 Earth diameters (359,500 km or 223,383 miles) from the Earth.

   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*

   Thursday evening May 14th, shortly after sunset local time (8:26 CDT), look toward the western horizon for a conjunction between a thin 1.25-day young waxing crescent Moon and the innermost planet Mercury. The two will be about 2-3o apart but very low over the western horizon.

   *Click here to read my 2006 Scope on the Sky column “The Real Shape of the Moon’s Orbit”. (PDF)

   Read this very informative article about the Earth-Moon system and their orbital motions, written by Joe Hanson. “Do We Orbit the Moon?”

   
   
   

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.


Also Follow me and other great resources at Feedspot.

May Perigee Moon in Conjunction with Venus

   Our Moon reaches perigee, (closest distance from Earth), for this orbit on Thursday May 17th. At that time the Moon will be at a distance of 28.52 Earth diameters (363,800 km or 226,055 miles) from the Earth.

   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*

   Thursday evening May 17th, shortly after sunset local time (8:26 CDT), look toward the western horizon for a conjunction between a thin 2.5-day young waxing crescent Moon and the inner planet Venus. The two will be about 5.5o apart. The respective apparent magnitudes of Venus (-3.95), and the Moon (-10.22) will make an interesting contrast. Despite the difference in the apparent magnitude of Venus and the Moon, which one appears brighter? Do they appear to be similar in apparent magnitude, or brightness?


   Using binoculars the Moon and Venus will be seen as forming the base of a small triangle with the open star cluster, M-35 (apparent magnitude 5.5) forming the point of the triangle.
   (the size of Venus and Moon are not to correct scale and in this graphic have been enlarged for the image)

   *Click here to read my 2006 Scope on the Sky column “The Real Shape of the Moon’s Orbit”. (PDF)

   Read this very informative article about the Earth-Moon system and their orbital motions, written by Joe Hanson. “Do We Orbit the Moon?”

   
   
   

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.

April Moon at Perigee


   Our Moon reaches perigee, (closest distance from Earth), for this orbit on Friday April 20th. At that time the Moon will be at a distance of 28.9 Earth diameters (368,714 km or 229,108 miles) from the Earth.

   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*


   On the day of the perigee Moon the 5-day old waxing crescent Moon is above the western horizon. The Moon is about 5o west (to the left) from the open star cluster, M-35.

   *Click here to read my 2006 Scope on the Sky column “The Real Shape of the Moon’s Orbit”. (PDF)

   Read this very informative article about the Earth-Moon system and their orbital motions, written by Joe Hanson. “Do We Orbit the Moon?”

   
   
   

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.

March Perigee Moon

   The Moon reaches perigee, (minimum distance from Earth), this month on Monday March 26th. At that time the Moon will more or less be at a distance of 28.90 Earth diameters (369,106 km or 229352 miles) from the Earth.
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*

On the day of perigee the 9.5-day old waxing gibbous Moon rises at mid-afternoon and is located between Procyon in Canis Minor and Regulus in Leo the Lion.

*Click here to read my 2006 Scope on the Sky column “The Real Shape of the Moon’s Orbit”. (PDF)

Read this very informative article about the Earth-Moon system and their orbital motions, written by Joe Hanson. “Do We Orbit the Moon?”


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.