February Apogee Moon

18mar-apogee_moon Our Moon reaches apogee, (greatest distance from Earth), on Saturday February 18th. At that time the Moon will more or less be at a distance of 31.70 Earth diameters (404,650 km or 251,438 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 as they both rotate around a common balance point, the barycenter.*

*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 day of the apogee Moon the 21-day old last quarter Moon rises a couple of hours before the Sun and is visible over the southern horizon before sunrise.

   
   
   

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.

Moon Near Jupiter and Spica


   Thursday January 19th morning several hours before sunrise local time the last quarter Moon will be within a few degrees from Jupiter and the blue-white star Spica in Virgo the Harvest Maiden.
This graphic simulates a view using 10×50 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.

Moon Passes Gas


   Over the next couple of nights, December 21st to 22nd the last quarter Moon will pass by the gas planet Jupiter coming within about 2o at 18 UT (12 pm CST) on the 22nd. The Moon rises around 2-3 hours after midnight local time and is over the southeastern horizon in the hour or so before sunrise.

   
   
   

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.

Moon Near Aldebaran

Thursday morning August 25th watch for the last quarter Moon to be either close to the star Aldebaran or occulting Aldebaran – depending on your location. This occultation will be visible from around Hawaii across the Pacific Ocean toward the southern United States of America and Estados Unidos de Mexico.
   Aldebaran is the reddish and brightest star in the constellation of Taurus the Bull and from mythology Aldebaran represents the angry eye of the bull. Aldebaran is also part of the v-shaped group of stars forming the face of the bull, and this group of stars, the Hyades, is also an open star cluster – a group of stars clustered together by their respective gravitational forces. The Pleiades, looking like a small dipper, is another nearby open star cluster and part of the Taurus constellation.

   
   
   

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.

July Perigee Moon #2

   The Moon reaches perigee, (minimum distance from Earth), this month on Wednesday July 27th. At that time the Moon will more or less be at a distance of 28.98 Earth diameters (369,662 km or 229,697 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 morning of the 27th the thin 23-day old last quarter Moon rises around midnight local time, and is west from the open star cluster the Pleiades.
   
   
   
   
   
   
   *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.

Mars at West Quadrature

orbital-positions   Sunday February 7th the position of the planet Mars, with respect to the Earth and the Sun, places this planet at what is called western quadrature. At that orbital position Mars, and actually any outer planet at their respective quadrature, is at a 90 degree angle from the Earth as this graphic shows, and the banner graphic at the top of the page shows. Think last quarter Moon as that is a fair comparison of the relative positions of Earth, Sun, and Mars. At this position Mars leads the Sun across the sky from east to west as the Earth is rotating, meaning that Mars rises before the Sun.
   Sunday morning finds Mars and the other visible planets spread across the morning skies from east to west.
   This is a short video clip about Mars from a much longer video that I made as part of a live musical performance called “Orbit” at the Gottleib Planetarium in Kansas City Missouri during May 2011.

   
   
   

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.

A Missing Star!

   Saturday morning September 5th there will be a star missing from a familiar formation of stars as they rise in the east. Those familiar with the constellation Taurus the Bull know that the face of the bull is depicted by the stars of the Hyades, a ‘V-shaped’ open star cluster. At the lower end of the ‘V’ is the bright reddish star Aldebaran, marking the angry eye of the bull. aldebaran-aniHowever on this particular morning, at least for a while, Aldebaran will be missing.
   So what is happening? The last quarter Moon will occult, pass in front of’, the reddish star Aldebaran in the constellation Taurus the Bull. Most of the duration of the occultation event will be visible from parts of Europe and the eastern coast of North America. A timetable of beginning and ending times and showing cities where the occultation will be visible from may be found at the IOTA (International Occultation Timing Association) web site.
click on animation to see it larger    Viewing the event will obviously depend on your local weather, however your longitude and latitude will determine what if any of the event you will see. For example at my longitude of 94oW the last quarter Moon does not rise until midnight CDT and at that time the occultation will already be in progress.

   
   
   

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.