Mark March 20, 2015 on your calender. If that day rings a bell, you might be pondering the spring equinox – a conclusion worthy of honourable mention yet no blue ribbon because this March equinox is so much more.
In a nutshell, the Earth has a wobbly axis. Twice a year (March and September) the “plane” of Earth’s equator passes the center of the sun, at that point our axis tilts neither away or towards the sun. Imagine a line perpendicular to the equator, a brief time when northern and southern hemispheres are illuminated equally – you have the equinox. Think of it as roughly equal hours of day and night. Due to a blinky wobble in Earth’s axis, this happens at different times each March, roughly on the 20th or 21st.
Lets talk Moon. A super-moon occurs when a new or full moon happens at the “perigee” or closest point of orbit to Earth. 2015 officially has 6 super-moons – new moons in January, February and March, full moons in August, September and October.
Moving on to Sun – a solar eclipse only happens when a new moon passes between Earth and the Sun, casting a shadow on our planet. This conjuncture, or “syzygy” causes the Moon to fully obscure the sun’s “disc”, resulting in shadows cast upon earth.
So we have equinox, super-moon, and solar eclipse – what are the chances of them happening at the same time? If you guessed not very likely, I award you that blue ribbon.
Enter March 20, 2015 – one of those few days when cosmic circumstance delivers. If you miss this one, you’ll have to wait until 2034, 2053, or 2072.