Jupiter Backs Up!

   Friday March 9th the outer ringed planet Jupiter stops its regular direct motion to the east and begins to move in retrograde toward the west. Retrograde motion for any planet further from the Sun then the Earth, that we observe from Earth, is an apparent motion of that planet caused by the faster moving Earth along its orbital path. As the Earth catches up and passes an outer planet that planet appears to move toward the west. Depending on the planet the retrograde motion may last a few weeks or months. Jupiter will be within the boundaries of the constellation Libra the Scales.

   Jupiter along with Mars and Saturn all rise before sunrise local time and the morning skies on March 9th the 21-day old last quarter Moon will be about 7o from the ‘red planet’ Mars.

   Follow the planet by way of its coordinates using just right ascension with the free equatorial star chart from Stephen F. Austin University.

Date Right Ascension
(Hours – Minutes)
June 5            14 52
June 15         14 48
June 25         14 46
July 5            14 45
July 15            14 44
July 25            14 46
August 4          14 48
August 14         14 51
August 24         14 55
September 3      15 00

   
   
   

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.

Jupiter Goes Retro

   The giant outer planet Jupiter slows down and reverses its orbital motion on Monday February 6th as it begins its more or less annual retrograde motion. Retrograde motion is an apparent motion that occurs for an outer planet (past Earth’s orbit) when the faster moving Earth catches up with and then passes by the outer planet. During this retrograde motion Jupiter will move westward starting near the blue-white star Spica in Virgo the Harvest Maiden.

   Jupiter currently rises about around midnight local time and is very visible above the southwestern horizon 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.

Jupiter Pulls A Reversal

Jupiter Retrograde Motion: 7 November 2013-6 March 2014

Jupiter Retrograde Motion: 7 November 2013-6 March 2014

   Since 7 November 2013 the giant planet Jupiter has been moving westward, or at least it has appeared to be moving westward when in fact it has been in retrograde motion. This is an apparent motion that occurs for an outer planet when the faster moving Earth catches up and then passes by the outer planet. As has been previously and recently posted the planets Mars and Saturn have just begun their respective retrograde motions. Jupiter, today, reverses all of that as the angle between the Earth and Jupiter has increased to the point where Jupiter now is moving in its ‘correct’ direction, toward the east in what is called direct motion.
Click on graphic to see it full size.

Click on graphic to see it full size.

   Jupiter is currently very visible high overhead at local sunset time, and forms the point of a triangle with Pollux and Castor. This graphic shows the region of bright winter stars near Jupiter and the waxing crescent Moon.

   
   
   
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.