Here's why:
* Gravity: The Sun's gravity pulls on the Earth, but the Earth's speed also keeps it from falling directly into the Sun. This balance results in an elliptical path.
* Kepler's Laws: Johannes Kepler, a famous astronomer, discovered that planets orbit the Sun in elliptical paths, and this is one of his laws of planetary motion.
So, while we often depict Earth's orbit as a circle for simplicity, it's important to remember that it's actually a slightly squashed oval.
