The statement is false. The shape of Earth's orbit doesn't change "all the time" in the sense of constant, rapid fluctuations.

Here's why:

* Orbital Eccentricity: Earth's orbit is elliptical, meaning it's not perfectly circular. The degree of this "oval-ness" is called eccentricity.

* Gravitational Influence: The shape of Earth's orbit is primarily influenced by the gravitational pull of the Sun and the other planets in our solar system. These forces cause subtle changes in eccentricity over very long periods.

* Milankovitch Cycles: These cycles are long-term variations in Earth's orbit, including changes in eccentricity. They occur over tens of thousands to hundreds of thousands of years. These cycles are a key driver of Earth's climate change over geological time scales.

In summary: While Earth's orbit does change over time, it's not a constant, rapid fluctuation. The changes in eccentricity are subtle and occur over long time scales due to the complex gravitational interactions within our solar system.