Write a paragraph about the universe.

The Universe is all of space and time and its contents, which includes planets, moons, minor planets, stars, galaxies, the contents of intergalactic space and all matter and energy. The size of the entire Universe is still unknown with the latest figure, calculated by Halpern and Tomasello after the data from European Space Agency's Planck satellite estimating it to be 90.68 billion light-years across, 0.7% smaller then previously thought. The earliest scientific models of the Universe were developed by ancient Greek and Indian philosophers and were geocentric, placing Earth at the centre of the Universe. Over the centuries, more precise astronomical observations led Nicolaus Copernicus to develop the heliocentric model with the Sun at the centre of the Solar System. After all of the information given ... there are still scientists and astronomers examining and trying to find answers to questions about the universe.