Day and night are 12 hours each around the globe today — except at the poles — as the Earth reaches equinox. But in the fortnight (a period of two weeks) after the autumnal equinox — and the fortnight (a period of two weeks) before the spring equinox — in the southern hemisphere, you may notice that your radio or TV broadcast briefly drops out. If you're in a regional area, the internet might be patchy, too. What's going on? What is an equinox? If you were standing at the geographic equator and looked up during an equinox, you'd see the Sun pass directly overhead. It's the point at which the Sun appears to traverse the equator from the Earth's perspective, shining equal light on both hemispheres. The Earth's axis is tilted 23.5 degrees. As it travels around the Sun, different parts of the planet are tilted more directly at the Sun. This is what causes the seasons in the temperate parts of the world. In an Australian summer, the southern hemisphere is tilted towards the Sun, and in our