The Geminids-2017

   A few hours after sunset local time, on Wednesday December 13th, look toward the west for ‘shooting stars’, or meteors coming from the area around the constellation the Gemini Twins. These are the annual Geminid Meteor Shower – one of the best meteor showers each year, and at times rivaling the August Perseid Meteor Shower. The calculated peak time for the meteors is December 14th at 7 UT (2 am CST), but this does not mean that is the only time to view them. The Geminid Meteor Shower is named for the constellation that the meteors radiate outward from. This is the same for all meteor showers, and the ‘spot’ in the sky is known as the radiant. The Geminid radiant is just above the ‘twin’ star Castor, and under ideal viewing conditions an average of about 70 meteors per hour could possibly be seen. This year without the interference of moonlight will increase the chances of seeing the meteors.
   Meteor showers result from the Earth’s orbital path intersecting areas of comet debris. Comets, as they orbit the Sun, leave behind pieces of their icy, dirty, selves. If these debris clouds happen to be along the Earth’s orbital path then the Earth will regularly pass through the comet debris cloud. As this happens the small comet pieces hit our outer atmosphere and vaporize from the friction generated heat. We then see these as the shooting stars that make up meteor showers.
   There are, however, two exceptions to this. The January Quadrantid Meteors and the Geminids each come from their own respective asteroid rather than a comet. The source for the Geminids is Asteroid 3200 Phaethon

   
   
   
   

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

November Moon at Descending Node


   Saturday November 25th the waxing crescent Moon will be crossing the plane of the ecliptic moving south. This is known as the descending node, one of two intersections the Moon’s orbital path (dark green line) has with the ecliptic.
   

   On the day of the node crossing the 7.5-day old waxing crescent Moon will be over the southwestern horizon an hour or so after sunset local time.
   
   
   
   

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.

November Moon at Apogee

   Our Moon reaches apogee, (greatest distance from Earth), on Tuesday November 21st. At that time the Moon will more or less be at a distance of 31.84 Earth diameters (406,132 km or 252,359 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 apogee the 3.5-day old waxing crescent Moon will be over the southwestern horizon at sunset local time. Were it not so bright the glow of the Milky Way in the background might have been visible. Saturn is visible, but it is low above the 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.

Waxing Crescent Moon Conjunctions with Mercury and Saturn

   Over the next two evenings, November 19th and 20th the waxing crescent Moon will be passing by the innermost planet Mercury and then one of the outer planets, Saturn. The thin 1.5-day old waxing crescent Moon will be near Mercury on Sunday the 19th, and then the 2.5-day old thin waxing crescent Moon will be near Saturn on Monday the 20th.

   
   
   

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 Splits the Distance


   Wednesday morning November 15th the thin 27-day waning crescent Moon will be located more or less between the planet Mars and the bluish-white star Spica in Virgo the Harvest Maiden.

   
   
   

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 Conjunction with Mars and Spica


   Tuesday morning November 14th the waning crescent Moon will be within a few degrees from the ‘Red Planet’ Mars and the bluish-white star Spica in Virgo the Harvest Maiden. Then as this animated graphic illustrates the waning crescent Moon will pass by Jupiter and then Venus over the next few days.

   
   
   

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.

Venus – Jupiter Close Conjunction

   Monday Morning November 13th the inner planet Venus and one of the outer planets, Jupiter, will have a very close conjunction with Venus coming within less than one-half degree from Jupiter. Adding to the celestial scenery is the planet Mars and the 25-day old waning crescent Moon.

   Both should make for a striking view with binoculars or a low-power telescope eyepiece, or as a picture. Venus will be shining at a -3.9 apparent magnitude compared with Jupiter’s -1.7 apparent magnitude.
This graphic shows a view using a 25mm eyepiece on a 6″ Dobsonian Telescope.

   
   
   

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.