March Moon at Apogee

 Our Moon reaches apogee, (greatest distance from Earth), on Saturday March 18th. At that time the Moon will more or less be at a distance of 31.72 Earth diameters (404,640 km or 251,432 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*

*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?”

   On the morning of the apogee Moon the 20-day old waning gibbous Moon rises a couple of hours before the Sun and is visible over the southern horizon.

   
   
   

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.

Follow the Moon

   Over the next several days the Moon, as it waxes toward full phase, will follow the ecliptic as it passes by some of its solar system colleagues. Starting on the 15th, a few degrees east from the blue-white star Spica in Virgo the Harvest Maiden, the waxing gibbous Moon will then pass a few degrees from Mars on the 16th and 17th. Then on the 18th the nearly full Moon will be about 3o from Saturn, and that night ending this month’s lunar sweep along the ecliptic and bright planets.
   This animated graphic shows an 'atlas' view of the area along the ecliptic and the the Moon's daily path from June 15th to the 20th. The celestial equator is the curved red line and the ecliptic is the green line.
   There are two distinct motions, and one subtle motion shown in this animation.

    -Planets are in motion with Saturn and Mars on the move with Mars moving toward the west as it retrogrades. On a day to day basis the subtle shift in the position of Saturn and Mars each day is relatively small. Saturn moves 0.033o each day (360o/10,755 Earth days), and Mars each day moves 0.52o (360o/687 Earth days) .
    -The Moon orbits from west to east so each day at the same time the Moon is further to the east, or rises (sets) later.
    -The daily shift in the sky from east to west due to the Earth’s revolution around the Sun. The sky shifts about 1 degree each day or celestial objects, like stars, rise (and set) about 4 minutes earlier each day.

   The graphics below are set for 10 pm CDT on the dates indicated.

This slideshow requires JavaScript.

   
   
   

Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Moon Sort of in Conunction with Mars and Saturn

click on graphic to see it full size
   Monday morning April 25th the 18 day old waning gibbous Moon will be within a few degrees from the planet Mars and a few more degrees from the planet Saturn. Not really a true conjunction but the trio will all fit within a 7×50 binocular field of view.

25apr-bino   
   
   
   
   
   The reddish star Antares, the ‘heart’ of Scorpius the Scorpion is 4-5o south from Mars and is just outside the binocular field of view.

   
   
   
   
   
   
   
   

Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Mars and Saturn – Close But Not For Long


   The planet Mars, having just begun its retrograde motion, will come within about 7o from Saturn this Wednesday April 20th. This is the closest the two planets will be for a while as the separation between the two increases while Mars retrogrades toward the west.

   
   
   

Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Sun Enters Sagittarius

16dec-view-from-earth   Friday December 18th the Sun in its apparent eastward motion along the ecliptic, moves out of the constellation Scorpius the Scorpion and into the constellation of Sagittarius the Archer. This is the true or actual position of the Sun as opposed to the pseudoscience of astrology which usually has the astrological Sun one constellation ahead or east from the Astronomical Sun’s position.

   Read a little more about how astrology has the Sun incorrectly placed in a previous blog, and in another blog discussing the effects of precession.
   
   
   

Caution: Objects viewed with an optical aid are further than they appear.
   Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Moon ‘Hearts’ the Scorpion

   Sunday and Monday evenings, July 26th and 27th the waxing gibbous Moon will pass the heart of Scorpius the Scorpion, the reddish star Antares. This animated graphic shows the evening sky at 10:30 pm CDT on the 26th and 27th.

   
   
   
   

Caution: Objects viewed with an optical aid are further than they appear.
Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Planets – Big and Small

   Saturday July 25th the waxing Gibbous Moon, just past first quarter phase, will be within a few degrees from the planet Saturn. During this conjunction the two will rise at around local time, and be visible throughout the length of the night. Down to the left from the Moon and Saturn look for a reddish star. This is Antares, the heart of Scorpius the Scorpion.
   Closer to the Earth the dwarf planet Ceres moves into an orbital position known as opposition. Only Sun orbiting objects beyond the Earth’s orbital distance may be at opposition, with an arrangement of the Sun-Earth-outer orbiting object.
   Ceres rises before midnight local time and would be visible throughout the length of the night. Currently NASA’s Dawn Mission spacecraft is now in orbit around Ceres.

   
   
   
   

Caution: Objects viewed with an optical aid are further than they appear.
Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.