Mars on the Move

   Friday morning January 17th, before sunrise, the last quarter Moon will be about 5-6o from the blue-white star Spica in Virgo the Harvest Maiden. However the celestial highlight coming up is further east or lower and closer to the eastern horizon where there are two reddish-colored objects of about the same apparent brightness or magnitude. One object is the planet Mars and the other is the star Antares in Scorpius the Scorpion.

click on animated graphic to see it larger

Mars passing Antares – January 17-23 – 6 am CST

   Watch over the next several mornings and you will be able to determine which one is Mars and which is Antares as one of them moves past the other – as this animated graphic is showing. Also, relative to Mars and Antares the Moon is waning in phase as it zips past the two.

   There is an interesting connection between the star Antares and the planet Mars, based on their similar reddish color. There are times like this year when the two are close and part of the mythology surrounding the two suggests that the star was given its name so as to not confuse it with the planet Mars. The name Antares comes from the Greek word translated to ‘Rival of Mars’.

   Whenever that was historically Mars was probably known as one of the ‘wandering stars’ from the Greek word ‘planetai’. So with its reddish color, like blood, this ‘wandering star’ came to represent Mars, the ‘G-d of War’. Antares, on the other hand is a red supergiant star with a diameter estimated to be such that if it were at the center of our solar system Antares would fill the solar system out to around the main asteroid belt between Mars and Jupiter.

   
   
   

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.

Saturn at Solar Conjunction – 2019

   Monday January 13th the planet Saturn will have reached the astronomical coordinates that officially place it at solar conjunction. From our perspective the planet is behind the Sun, or on the opposite side of the Sun from the Earth.

   In reality it is not as much as Saturn moving behind the Sun as it is the Sun passing in front of Saturn – or so it seems. As a distant outer planet Saturn moves more slowly around the Sun than the Earth does. One year on Saturn is equal to 29.7 years (10,832 days) on Earth. So in one Earth day Saturn would travel how much of the 360o orbit around the Sun? That would amount to approximately 0.033o each day.

   The Sun, in its apparent motion along the ecliptic moves at the rate the Earth is moving which is 0.99o each day. So with the Sun’s apparent motion (0.99o/day) it quickly, relative to Saturn, passes Saturn while both are moving eastward. This animated graphic starts with Saturn and the Sun above the horizon a couple of hours after sunrise. The animation is set for 1-day intervals showing the Sun moving eastward away from Saturn. The sky is purposely left dark to show Saturn more easily.

   So with that in mind you could start watching for Saturn to reappear in the morning skies later next 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.


Also Follow me and other great resources at Feedspot.

Moon – Venus Conjunction

   Friday evening December 28th over the western horizon around sunset look for the 3-day old waxing crescent Moon to be about 2o from the inner planet Venus. Both will easily fit within the field of view of binoculars.

   I should clarify that the view of the conjunction as described above is based on my latitude and longitude in the midwest U.S.A. The separation between the Moon and Venus will vary depending on your location. At other geographic locations, like southern South America and Antarctica, the crescent Moon occults Venus.

   The occultation begins at 2 UT or for my time zone at 9:00 pm CST.

   This animated graphic is set for a latitude of 56oS to show the Venus Occultation. Venus was also enlarged to make it more visible in the graphic.

   
   
   

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.

Waning Crescent Moon Near Mars

   Monday morning before the Sun rises the 27-day old Moon waning crescent Moon will be about 4-5o from the ‘Red Planet’ Mars. Both will be over the southeastern horizon rising at least 2-3 hours ahead of the Sun.

   
   
   

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.

Moon on the Move

   Over the next few evenings, Saturday December 14th, Sunday the 15th, and Monday the 16th the waning gibbous Moon will orbit eastward starting from about 7-8o south of Pollux to passing about 6-8o from M-44, the ‘Beehive Cluster’, an open star cluster in the constellation Cancer the Crab. By Monday the 16th the waning gibbous Moon will be about 2o from the heart of Leo the Lion, the star Regulus.
   During a 24-hour rotation of the Earth the Moon will have moved approximately 15o eastward. In terms of Moon position that 15o is equal to one hour — (divide 360o by 24 hours = 15o). What this has to do with the Moon’s position is that each day or night the Moon rises about 1 hour earlier. These 3 graphics show the effect of this in that it will be about 1 hour later for the Moon to be more or less in the same spot in the sky relative to the horizon.

   
   
   

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.

Venus – Saturn Conjunction

   Wednesday evening November 11th look toward the western horizon for a grouping of 3 planets and one dwarf planet. Very low over the horizon and possibly to low to be seen is the outer planet Jupiter. About 7-8o east from Jupiter is the dwarf planet Ceres, however at nearly 9th magnitude and low above the horizon Ceres will be difficult to see, if at all.
   Several degrees east from Jupiter and Ceres is the brightly shining inner planet Venus and about 1-2o from Venus is the outer planet Saturn. These two planets will make a nice contrast in apparent magnitude (Venus: -3.95 Saturn: 0.57) as they easily will 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.


Also Follow me and other great resources at Feedspot.

Moon Conjunction with Aldebaran

   Tuesday evening, November 10th, about an hour or so after sunset, the 14.5-day old waxing gibbous Moon will be about 2-3o from the reddish star Aldebaran. Aldebaran is at one end of the v-shaped open star cluster the Hyades in Taurus the Bull.

   
   
   

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.