April Moon at Perigee


   Our Moon reaches perigee, (closest distance from Earth), for this orbit on Friday April 20th. At that time the Moon will be at a distance of 28.9 Earth diameters (368,714 km or 229,108 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 perigee Moon the 5-day old waxing crescent Moon is above the western horizon. The Moon is about 5o west (to the left) from the open star cluster, M-35.

   *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.

Sun Enters Astronomical Sign of Aries

April 19th   Thursday April 19th the Sun in its apparent eastward motion along the ecliptic, moves out of the constellation Pisces the Fishes and into the constellation of Aries the Ram. 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.
   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.

Moon Traverses Taurus


   Wednesday and Thursday evenings March 21st and 22nd the waxing crescent Moon will pass across the constellation of Taurus the Bull. It will first be several degrees from the open star cluster the Pleiades and then the next day the Moon will be within 1-2o from the reddish star Aldebaran and the open star cluster the Hyades. The latter should prove to be a striking sight through 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 Gets A Bullish Headbutt

   Friday evening February 23rd the 8-day old waxing gibbous Moon will be about 6o from the reddish star Aldebaran, part of the open star cluster the Hyades. The brighter stars of the Hyades are arranged in a v-shape that is used to represent the face of Taurus the Bull. The point of the V is the Bull’s nose and the reddish star Aldebaran is one of the Bull’s eyes, often depicted as the ‘angry eye’ of 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.

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.

Lunar Eclipse – January 31 2018

Here are two pictures from the rising Moon last evening.

   
   And this morning got a late start out the door – made a mistake and let the dogs out in front (north side) while I looked to see where the Moon was. Then chased the ‘guys’ for a while until they peed and sniffed enough and got them back inside.
Drove out east to our community park for a better horizon. Had planned on using 3 cameras but then applied the KISS or Occam’s Razor logic and set up one camera. In reality I had about 30 minutes prior to totality and only a couple of minutes as you see in the video near totality. The clouds were too thick near the horizon.
   This is a sequence taken at 300mm with several exposure times, f-stop and ISO changes along the 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.

A Lunar ‘4-fer’ Plus Planets: Perigee; Ascending Node; Blue Moon; and a Total Lunar Eclipse!!

   Our Moon reaches full phase for the second time this month on Wednesday January 31st at 13:27 UT (7:27 am CST). According to the popular definition for a ‘Blue Moon’ the second full Moon in a month is known as the ‘Blue Moon’. This happens about every 2.5 years with this year being a little more different in that there will be a second Blue Moon month in March.

   Our Moon reaches perigee, (closest distance from Earth), for this orbit on Wednesday January 30st at 9:48 UT (3:38 am CST). At that time the Moon will be at a distance of 28.14 Earth diameters (358,994 km or 221,204 miles) from the Earth.

      On Wednesday January 31st the full Moon will be crossing the plane of the ecliptic moving north relative to the ecliptic. This is known as the ascending node, one of two intersections the Moon’s orbital path has with the ecliptic. The ecliptic is actually the Earth’s orbit and the Moon’s orbit is inclined about 6o from the ecliptic. So there are two node intersections, the ascending and descending nodes.
      
   What do you get when you have the full Moon at a node crossing? An eclipse – in this case a total lunar eclipse. Timing for this eclipse favors viewing from the western half of the continental United States. Here is a link to download a lunar eclipse page information page (PDF) from the NASA eclipse web site
   Mid-eclipse has the darkened Moon a few degrees away from the open star cluster, M-44, commonly known as the Beehive Cluster. Both the Moon and tM-44 will fit within the field of view of binoculars.
   Here is a summary of the eclipse event starting times from the NASA Eclipse web site. My local time, CST, is UT-6 hours. An important time will be local sunrise-moonset time. For me local sunrise and Moon set time is 7:26 am CST meaning that totality will be in progress as the Moon sets. Here is a link to the Sun and Moon Data calculator web page at the U.S.N. Observatory so you may determine your local sunrise/moon set time. Here is a link to the Hermit Eclipse web site for more information about the eclipse and an interactive map showing eclipse event particulars.
P1 = 10:51 UT 4:51 CST
U1 = 11:48 UT 11:48 CST
U2 = 12:51:47 UT 6:51 CST
U3 = 14:07:51 UT 8:07 CST
U4 = 15:11:11 UT 9:11 CST
P4 = 16:08:27 UT 10:08 CST

   As the eclipsed Moon is setting in the west turn toward the south and east to see Jupiter, Mars, and Saturn plus the bright stars Spica and Antares.

   
   
   
   
   
   

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.