by Aldo Hugo Olguín
Professor of Mathematics, Physics and Cosmography
September is the Equinox month on Planet Earth. More precisely, next Thursday 23rd we are having 12 hours of light and 12 hours of darkness across the globe. The sun will rise in the east and will set in the the west; it will be walking a circle on the celestial sphere, called Celestial Equator.
By observing the position of the sun at noon, we can see our shadow projected from north to south, and if we extend an arm, and rise the other vertically upward, the resulting angle will give us the latitude of the place where we are standing, which for San Luis is over 30 °.
Spring officially begins on September 23rd, but in Argentina, it is traditionally celebrated on the 21st, together with the Students’ Day.
At the beginning of the night, the most populated sector of the Milky Way will be above us, and we will be able to watch the constellations of Scorpius, Sagittarius, Capricorn, Aquarius, Pisces, etc.
If we look to the South, at the beginning of the night, we will be able to see the Magellanic Clouds, two beautiful sister galaxies in the Milky Way.
On September 11th, the Teacher's Day in Argentina, the moon will be next to Venus at dusk. Look to the West.
On September 20th and 21st, the Moon will be next to Jupiter all night long. Look to the East.
After September 27th and at the beginning of the 28th, at midnight, we will see the old moon rising from the north-east, next to the Pleiades, also called the Seven Sisters. This is a beautiful celestial spectacle. We will see the Moon near these bright stars!
October, may give us a surprise at dawn with a shooting star, so make a wish!
Happy Springtime to you all!
