On Tuesday September 22nd at 13:32 UT, (8:32 am CDT) the Sun will have reached the astronomical coordinates of 0 degrees declination and 12 hours of right ascension, or RA. This places the Sun within the boundaries of the constellation Virgo the Maiden, or as some would say, “the Sun is in Virgo.” This is the actual position of the Astronomical Sun as opposed to the pseudoscience of astrology which has the astrological Sun entering the constellation of Libra the Scales.
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.
Declination is the astronomical equivalent to latitude measuring from 0 degrees at the equator to 90 degrees at either pole. Right ascension, or RA, is like longitude except that there is only east RA. The globe is divided into 24 sections, and like meridians of longitude, these hour circles are 15 degrees wide at the celestial equator and taper to a ‘point’ at the north and south pole respectively. In RA the ‘hour’ circles are counted from 0 hours to 23 hours. The 0 hour circle is at the intersection of the ecliptic and the celestial equator in the constellation of Pisces the Fishes.
In a class lesson about seasons today would be one of the two days during the year when the Sun would be described as being over the Earth’s equator. If you were at the Earth’s equator the Sun would have an altitude of 90 degrees, or straight up in your sky at your local time for midday. At that moment there would not be a shadow. However at any other latitude, north or south at midday, the Sun would be at an angle less than 90 degrees and there would be a midday shadow. (Midday is the local time when the Sun is halfway between local rising time and local setting time. At any midday the Sun is at its maximum altitude above the southern horizon in the northern hemisphere, or is at its maximum altitude above the northern horizon in the southern hemisphere.)
What is often noted about an equinox day is the reminder that equinox means equal night as a reference to there being equal amounts of daylight, and night. Also on an equinox day the Sun would rise due east and set due west for virtually everywhere on the globe. The times for sunrise and sunset would be approximately 12 hours apart, and the rising time would be around 6 am local time, and the setting time would be around 6 pm local time.
Hola ‘Moo’ndo! Think Globally.
This short video shows students at Colegio Menor San Francisco de Quito, a school in Quito Ecuador, measuring the altitude of the sun hourly on the day of the 2004 September Equinox. They were taking part in Project SunShIP, Sun Shadow Investigation Project. There are also some pictures showing a local midday shadow from other participating schools in the United States and U.K.
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.
Also Follow me and other great resources at Feedspot.
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*
Wednesday September 16th the Sun in its apparent eastward motion along the ecliptic, moves out of the constellation of Leo the Lion and into the constellation of Virgo the Harvest Maiden. 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.
Wednesday September 10th the 22-day old last quarter Moon will be crossing the plane of the ecliptic moving north. This is known as the 
Does our Moon actually go around the Earth as many graphics show? 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*
Look at the arrangement of the planets in the graphics below. One of the defining aspects of our solar system is the arrangement of the planets outward from the Sun. Not by size or distance but rather how their respective orbital paths around the Sun are all vertically arranged near the Earth’s orbital path, or as it is typically referred to as the Ecliptic or the Plane of the Ecliptic. The 8 classic planets all orbit the Sun with an orbital path that is up to about 8o from the ecliptic. This is called inclination. The table shows inclination relative the Earth’s orbit and also relative to the Sun’s center, its equator.
