Six Visible Planets Now Visible!


   Over the next few evenings the two inner planets will come within less than a degree from each other and then pass by as each moves eastward away from the Sun along their respective orbits. This animated graphic is set for my local sunset time of 8:41 pm CDT and cycles through each graphic at 1-day intervals starting with Saturday July 16th and ending on the 20th. The graphic also illustrates how low the two inner planets are relative to the position of the Sun at the horizon and how challenging it may be to see them due to local horizon circumstances.
   Not only are the two inner planets visible but stretching across the horizon to the east from Mercury and Venus are 3 more visible planets, Jupiter, Mars, and Saturn, and of course at your feet is the 6th visible planet, Earth. At times like this, with several of the 8 planets above the horizon it is easy to visualize the ecliptic by sort of connecting the dots (planets). The 8 planets all orbit the Sun with orbits that are close to being parallel to the plane of the Earth’s orbit, the ecliptic, with none of the 8 planets having an inclination, tilt, of more than 7o away from the ecliptic.

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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.

June Solstice 2016

21june-ecliptic   Northern hemisphere spring comes to an end and its summer begins on Monday June 20th at 22:34 UT (5:34 pm CDT) when the Sun ‘reaches’ the celestial coordinates of 23.5o north declination and 6 hours right ascension. With respect to the Earth’s surface the Sun is described as over the Tropic of Cancer, 23.5o, north latitude of the Earth’s equator. At this same time the Sun is still within the boundaries of the constellation Taurus the Bull – but just barely. Interestingly about 8 hours later, June 21st at 8 UT (3 am CDT) the Sun ‘will move’ into the region of Gemini as it crosses the boundary between Gemini and Taurus.
   According to the pseudoscience of astrology the Sun, at this date, would be entering the astrological sign of Cancer the Crab.
Just had to include this!!   We know that it is the Earth’s orbital motion around the Sun that causes the sun’s apparent eastward motion among the stars in the background. This is how the Sun ‘reaches’ a celestial coordinate, how it ‘crosses’ the boundaries between constellations, or how it is ‘in’ a constellation.
   With respect to the southern hemisphere this is the end of their summer and start of their fall season. So thinking globally my preference has been to use the name of the month to designate the season change. Hence the use of the term June Solstice rather than summer solstice.

   
   
   
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.

Moon and Spica – Together Again!

   Wednesday and Thursday July 22nd and 23rd, respectively, the waxing crescent Moon will pass within a few degrees from the bluish-white star Spica in the constellation Virgo the Harvest Maiden. This is a fairly regular occurrence, the Moon passing close to Spica, because Spica is only a few degrees from the ecliptic. The Moon, likewise, is located near the ecliptic. Keep in mind that the Moon’s orbit is inclined about 6o from the ecliptic so that the Moon’s orbital path places the Moon above, on, or below the ecliptic throughout the month. The point along the Moon’s orbital path where it crosses the ecliptic is known as a node. One the descending and the other the ascending node. A significance of the node crossing is that if it occurs at or close to either a new Moon or full Moon there will be an eclipse. (watch for my postings about these node crossing events)

   
   
   
   

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.

Mercury at Inferior Conjunction

orbital-positions   Saturday May 30th at 17 UT (12 pm CDT) the innermost planet Mercury reaches inferior conjunction. At inferior conjunction Mercury will move between the Earth and the Sun – much like the position of the Moon at new phase. The graphic to the right shows the planet positions relative to the Earth and Sun for both inner planets and outer planets.

mercury at inferior conjunction   While at inferior conjunction Mercury is not directly in line with the Earth and the Sun – on the ecliptic. Mercury has an orbital inclination of 7o with respect to the ecliptic. So like our Moon Mercury, during each complete orbit, will cross the plane of the ecliptic moving north (ascending node) and also moving south (descending node). This past May 23rd Mercury was at its descending node, and for those thinking ahead Mercury crosses the ecliptic moving north (ascending north) next month on June 24th.

   
   
   
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.

Sun Enters Aries

April 19th

April 19th

   Sunday April 19th at 4 am CDT, (10 UT), 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.
   
   
   

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.

Moon At Ascending Node

16dec--ascending-node
On Tuesday December 16th our Moon will be crossing the plane of the ecliptic moving north. This is known as the ascending node, one of two intersections the Moon’s orbital path (dark green line) has with the ecliptic.

Click on graphic to see it full size.

Click on graphic to see it full size.

Look for the 24-day old waning crescent Moon to rise a few hours before sunrise near the bright bluish-white star Spica.

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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.

October Moon at Ascending Node = Partial Solar Eclipse

23oct-ascending-node   On Thursday October 23rd our Moon will be crossing the plane of the ecliptic moving north. This is known as the ascending node, one of two intersections the Moon’s orbital path (dark green line) has with the ecliptic.
At about the time of the node crossing the new Moon will pass between the Earth and the Sun, causing a partial solar eclipse that will be visible during the late afternoon hours across much of the continental United States. The eclipse path will start off the coast of eastern Siberia, follow an eastward path across parts of Canada, and then travel south across the United States. Since the eclipse will happen in the afternoon in the time zones across the United States, it may be in progress as the Sun sets for some locations. So check the time of your local sunset and then use the online eclipse-time calculator from NASA to find the timing of the eclipse for your location.
solar-eclipse-ani   Alternately use the Eclipse Calculator at the Time and Date web site. Click here to see the times for Kansas City, MO – or to enter the name of your city.

Sun Not in Scorpio (aka Scorpius) Today

Click on graphic to see it full size.

Click on graphic to see it full size.

Coincidentally according to the pseudoscience of astrology on 23 October the Sun should be crossing the western boundary of Scorpio as it “enters” that constellation. In reality the Sun is still within the constellation of Virgo the Maiden.

[centup]
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.