About Bob Riddle

Currently: Retired Teacher (May 2017) but not yet finished learning and teaching. Column Editor, Scope on the Skies - Science Scope Magazine; NASA/JPL Solar System Educator Program - Solar System Ambassador Program

Waxing Crescent Moon Near the Pleiades


   Thursday evening February 22nd the 7-day old first quarter Moon will be 8-9o from the open star cluster the Pleiades, and about 7o from the open star cluster the Hyades. With my 10×50 binoculars the two star clusters are just out of the field of view, but become visible with a slight nudge of my head!

   
   
   

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.

Sun Not in Pisces


  According to the pseudoscience of astrology the Sun enters the constellation of Pisces the Fishes on Sunday February 18th. In fact the actual position of the Sun is still within the boundary of the constellation of Aquarius the Water Bearer, as this graphic shows. The Sun had just entered Aquarius 2 days ago.

   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.

   
   
   

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.

Mercury at Superior Conjunction

mercury at superior conjunction
   Saturday February 17th the innermost planet Mercury reaches superior conjunction – on the opposite side of the Sun from the Earth. For those that are curious, Mercury at superior conjunction is approximately 1.384 AU (128,650,837 miles; 207,043,453 km) from the Earth – the combined distance of the Earth to Sun distance plus the radius of Mercury’s orbit.
   Mercury is not visible while in conjunction with the Sun but within the next week or so Mercury will reappear on the east side of the Sun and start becoming visible over the western horizon at sunset.

   
   
   

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.

Sun Enters Aquarius-2018

feb-view from earth   Friday February 16th the Sun in its apparent eastward motion along the ecliptic, moves out of the constellation Capricornus the Sea Goat and into the constellation of Aquarius the Water Bearer. 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, which will be Sunday February 18th when the sun is not in Pisces according to astrology.

   
   
   

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.

February Moon at Descending Node


   Wednesday February 14th the thin waning 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 28-day old waning crescent Moon will be over the eastern horizon about an hour before the Sun rises. The Moon will reach new phase approximately 24 hours after this node crossing.
   
   
   
      

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 Meets Antares

   Monday morning February 12th the ‘Red Planet’ Mars will be within about 5o from the reddish star Antares, the heart of Scorpius the Scorpion. Both Mars and Antares currently have the same apparent magnitude of 1.03.
   Antares owes its name to its near matching color of the reddish colored planet Mars. I have often described the name Antares origin as meaning ‘anti mars’, to distinguish the star from the planet. Sort of like saying at times like now when they are close that ‘that reddish object is not Mars’. However the name Antares from the Greek really means ‘equal to Mars’

   This part of the sky, the summer sky for the northern hemisphere, has probably the best view of the Milky Way despite it being early morning. So it is with a great deal of excitement that as Mars approaches Antares and soon Saturn Mars is moving closer to the Milky Way.

   
   
   

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.

February Moon at Apogee

   Our Moon reaches apogee, (greatest distance from Earth), on Sunday February 11th. At that time the Moon will more or less be at a distance of 31.80 Earth diameters (405,700 km or 252,090 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 25.6-day old very thin waning crescent Moon will be over the eastern horizon at around sunrise local time and within about 2o from the ringed planet Saturn.

   Since the Moon and Saturn are in the area of the Milky Way this should make for interesting viewing with Binoculars and pictures,

*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.