Sun’s Apparent Motion Along the Ecliptic – from Taurus to Gemini
Northern hemisphere spring comes to an end and its summer begins at 12:04 am CDT (05:04 UT) on 21 June
as the Sun ‘reaches’ the celestial coordinates of 23.5oN and 6 hours right ascension. With respect to the Earth’s surface the Sun is described as over the Tropic of Cancer, 23.5oN 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 9 hours later, (9:00 am CDT – 14 UT)
, the Sun ‘will move’ into the region of Gemini as it crosses the boundary between Gemini and Taurus.
We know that it is the Earth’s orbital motion around the Sun giving rise to the sun’s apparent eastward motion amongst 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 the limited to northern hemisphere term summer solstice.
Follow the seasons by observing how vegetation changes during 1 year. The video below was produced by an Earth orbiting satellite operated by the NASA/NOAA Suomi National Polar Orbiting Partnership (NPP). It is a really interesting narrated tour of the Earth from orbit over a variety of geographic features and landscapes.
Just had to include this!!
Click here to go to the Qué tal in the Current Skies web site for more observing information.