Mercury: Planet of Speed and Craters
Updated: Apr 20, 2022
Mercury is a tiny planet in our Solar System covered in giant craters! DISCOVER what ancient people knew about Mercury and then CREATE your own Mercury crater cookies!
MERCURY FAST FACTS:
Mercury is the smallest planet in the Solar System
It’s also the closest planet to the Sun!
Although it’s so close to the Sun, temperatures on Mercury are both hot and cold. Temperature changes on Mercury are the most extreme in the Solar System.
Mercury’s surface is similar to our Moon (which we explored last week!). Mercury has the most craters, as its atmosphere is too weak to protect it against meteors smashing its surface.
Many ancient civilisations would have seen the planet Mercury in the night sky, but the ancient Greeks were the first to record it.
A TWILIGHT LOOK
The Greek astronomer and philosopher Timocharis was the first person in history to mention the planet Mercury. Since Mercury is closest to the Sun, it is difficult to see it from the ground. This explains why some early astronomers never saw Mercury. The strong light of the Sun meant that Mercury can only be seen in twilight.
Did you know that the ancient Greeks thought Mercury was two different planets? They called it “Apollo” when it shone in the mornings, and “Hermes” when it appeared after sunset. The ancient Egyptians called the planet Sabkou, and were the first to discover that Mercury actually orbited the Sun!
AT THE SPEED OF LIGHT
Let’s fast forward a few hundred years later, to the 4th century BCE. This is when the Greeks discovered that the planets “Apollo” and “Hermes” were actually one planet - the planet we know today as Mercury! They decided to stick with the name Hermes for this planet, naming it after their messenger god, Hermes, who travelled very quickly. Just like Hermes, Mercury moves across the sky faster than any planet.
MERCURY IN MYTH
In ancient Greek mythology, Hermes was the messenger god of commerce, trade and travel. The Roman name for the god Hermes was Mercury. In the end, the Roman name Mercury is the one we use for this planet. Hermes (or Mercury), swiftest of them all, can usually be seen wearing winged sandals. These give him super speed. Sometimes he is shown wearing a winged cap too!
METEORITES, CRATERS, AND SPACE COOKIES!
Let's explore Mercury’s craters by rolling up our sleeves and making some crater cookies!
BUT FIRST . . . CRATER EXPERIMENT!
Mercury is covered with craters of all sizes, big and small. There’s no air to protect the planet from meteorites, so when they crash down, it creates giant craters or holes in the planet’s surface!
1) Grab a pie pan and add just enough flour to create the surface of Mercury.
2) Throw some chocolate chip meteorites down onto the flower surface. Try throwing them at different heights, angles and even at different speeds – notice how they all affect the crater that forms.
Follow the recipe to create space cookies with chocolate craters!