I love astronomy. I hate astrology. Nevertheless, we have an astronomical event coming up soon that ties these two together. The Vernal Equinox happens this year on 20 March at 11.43. At that time, the Sun is directly over the equator. At the North Pole it is just rising, at the South Pole it is just setting. The two hemispheres of the Earth are illuminated equally and we have 12hrs of daylight and 12hrs of night1. Hence, equinox; equal night.
The point in the sky where the Sun does all this clever stuff is called the First Point of Aries. It is in Pisces, as it turns out, but it used to be in Aries. You will notice the use of two star signs here. They are genuine constellations in the sky. The fact that the First Point of Aries is in Pisces is because it slowly moves through all the zodiac star signs; something called the Precession of the Equinoxes. Our star sign is the constellation where the Sun was when we were born. Virtually all of us are given the wrong star sign by the astrological community2. That's why I hate astrology. It is all bollocks from the word go.
1 Neglecting atmospheric refraction; which you shouldn't.
2 They don't even include the 13th star sign Ophiuchus