March Equinox – 2021

   Saturday March 20th is an equinox day. While typically called the Vernal or Spring Equinox it is more globally appropriate to call this day the March Equinox as it is the start of Fall in the Southern Hemisphere. The official time for the equinox is 09:40 UT on the 20th which for my time zone is 5:40 am CDT. So for those in the northern hemisphere winter is ending and spring has ‘sprung’ (starts). From a geographical perspective we would describe the Sun as being over the Earth’s equator, and as this graphic shows there would be an equal amount of daylight and night on our planet as a result.
    At mid-day on the equator the sun is directly overhead and from that latitude you have no elongated shadow, just a ‘blob-like’ shadow at your feet as this picture of my feet taken at mid-day in Quito Ecuador shows.


   
    Regardless of your hemispheric preference get outside and cast a shadow!

   
   
  Northern hemisphere spring, Astronomically speaking, is when the Sun reaches the celestial coordinates of 0 hours and 0 degrees as it moves northward along the ecliptic crossing the celestial equator. At this location the Sun is just within the constellation of Pisces the Fishes and not entering Aries the Ram as the pseudoscience of astrology would have you believe.

    To learn more about the celestial coordinates click here to read a previous post about seasons and the equinox.

   Click here to see the online world sunlight map used to make the day/night graphic at the top of the page.


   Celebrate Solar Week March 22nd-26th. Click here to go to the Solar Week web site.

   
   
   
   During a trip to Quito Ecuador to visit one of the exchange student we had hosted, and her family, we spent the day at a Museum on the equator, Mitad del Mundo. I brought along my over-sized protractor knowing in advance that we would be at the museum. So at mid-day I had my wife stand on the equator (yellow line) and hold a string to the top of her head while Cathy, a sister of our exchange student, held the protractor. This was done during the summer so the Sun was over the northern horizon at mid-day and the Sun’s angle above the northern horizon was around 75o.

   Here is a short series of hourly pictures taken during the day on the September equinox on the equator in Quito Ecuador at Collegio Menor San Francisco de Quito, a private school that I visited and did the SunShIP project with (Sun Shadow Investigation Project).

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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 return to bobs-spaces.

Sun Enters Astronomical Constellation Pisces the Fishes

11 March 2014   Thursday March 11th the Sun in its apparent eastward motion along the ecliptic, moves out of the constellation Aquarius the Water Bearer and into the constellation of Pisces the Fishes. 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.

Neptune at 2021 Solar conjunction

   Wednesday March 10th the outer ringed planet Neptune will reach a point in its respective orbit where Neptune will be on the opposite side of the Sun as viewed from here on Earth. Neptune, or any of the other outer planets (Mars to Neptune), dwarf planets, or small solar system bodies beyond the Earth’s orbit, will all eventually reach this position on the opposite side of the Sun known as solar conjunction.
   For the two inner planets, Mercury and Venus, when they are at a similar position on the opposite side of the Sun, they are at superior conjunction.
   
   
   

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-2021


  According to the pseudoscience of astrology the Sun enters the constellation of Pisces the Fishes on Thursday 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.

Eppur Si Muove


   February 15th is Galileo Day.
   Quoting Galileo, “and yet it still moves”, in reference to the Earth actually orbiting the Sun. So how to acknowledge his achievements and contributions to modern Science? Read on…

   Jupiter’s Moons
   One enjoyable pasttime is to observe the constantly changing four largest moons orbiting Jupiter. Sometimes known as the Galilean Satellites, they are: Io, Europa, Ganymede, and Callisto. Named after Galileo who made many observations of the moons and from these observations and other observations led him to question the Geocentric model of the solar system. These four planet-sized moons are visible as small bright stars on either side of Jupiter and depending on the time and date of viewing their arrangement around Jupiter is never the same as this animated graphic, set to 1-Earth day intervals, is showing.
   Recreate Galileo’s observations of the Galilean satellites through the use of an online simulation, the Java applet, Juplet. Input dates or times to see the position of the four Galilean satellites.
The Juplet will display the planet and the satellite configuration for the date and time on the computer, or you could easily edit the date and time, and after pressing the Enter key see a different configuration. To keep track of these changes the position of each satellite relative to Jupiter could be drawn on a data table similar to Galileo’s data table.

   This video, ‘Orbs of Jupiter’, was one of the videos I made for a live musical performance at the Gottleib Planetarium at Science City in Kansas City MO. The original videos were made for full-dome projection – this one has been flattened. Music was written by Richard Johnson and performed by Rebecca Ashe (Flute) and Cheryl Melfi (Clarinet). Live and pre-recorded Electro-acoustical sampling by Richard Johnson and Daniel Eichenbaum. The soundtrack for the video is from the live performance by Dark Matter.

   
   
   

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.


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February Moon at Perigee & Spica Conjunction

   Our Moon reaches perigee, (closest to Earth), for this orbit, on Wednesday February 3rd. At that time the Moon will be at a distance of 28.8 Earth diameters, 229,986 miles (370,127 km) from the Earth.

   Before sunrise on the date of the perigee Moon the 20.4-day old waning gibbous Moon and will be about 7-8o from the star Spica in Virgo the Harvest Maiden.

   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*
   *Click here to read my Scope on the Sky column “The Real Shape of the Moon’s Orbit”. (PDF)

   
   
   
   
   
   

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.


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Conjunction – Elongation – Conjunction

   Saturday evening watch for the 11-day old waxing gibbous Moon to be in conjunction with and about 3o from the reddish star Aldebaran in the constellation Taurus the Bull.

   Earlier in the evening the innermost planet Mercury was visible over the western horizon shortly after sunset. Mercury, on this date, will be at its Easternmost Elongation for this orbit. At elongation, eastern or western, Mercury, and also Venus, will be as far ‘out’ from the Sun to the right or left as we see the inner planets from Earth. At eastern elongation the inner planets follow the Sun across the sky during the day and appear as evening planets over the western horizon. At western elongation the inner planets ‘lead’ the Sun across the Sky during the day which means they rise ahead of the Sun and are seen as morning planets.

   But Wait – there’s still more!
   Saturn reaches solar conjunction on this date. During solar conjunction for an outer planet that outer planet will either be too close to the Sun to be seen or is on the opposite side of the Sun. When an outer planet reaches solar conjunction it moves from the evening skies to the morning skies.

   
   
   

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.


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Sun Is in Capricornus not Aquarius


   Tuesday January 19th at 15 UT the Sun in its apparent eastward motion along the ecliptic enters the boundaries of the constellation Capricornus the Sea Goat. This is the actual location of the Sun.
   Interestingly, according to the pseudoscience of astrology, 6 hours later, at 21 UT Tuesday January 19th, the Sun should be entering the constellation of Aquarius the Water Bearer.

   
   
   

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.


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Waxing Crescent Moon – Mercury Conjunction

   Did you miss the 27-day old thin waning crescent Moon conjunction with Venus this past Monday morning? I did!
   Well there is an opportunity to see the thin crescent Moon on this side of new phase this Thursday evening January 14th. The 1.7-day young waxing crescent Moon will be over the western horizon in a line-up of sorts with Mercury, Jupiter, and Saturn all angled downward toward the western horizon. From Saturn to the Moon will span about 13o with Mercury, about 3-4o to the west, (down to the right) being the closest of the 3 planets.

   This animated graphic is set for 2-minute intervals starting at 5:30 pm CST.

   
   
   

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.


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Morning and Evening Conjunctions

   Monday morning and evening, January 11th, offer an opportunity for catching a pair of conjunctions. Low over the eastern horizon at sunrise is the 27.7-day old very thin waning crescent Moon about 3-4o from the inner planet Venus.

   This could be a chance to see the Moon when it is about 24-hours from its new phase.

   Low in the western horizon at sunset is the ongoing triple conjunction between Mercury, Jupiter, and Saturn. Monday evening will be the closest Mercury and Jupiter will be as Mercury continues moving eastward away from the two giant planets.

   
   
   
   
   
   
   
   
   

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.


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