As the planets continued to cool in the absolute cold of space, their gravity began to increase in proportion to their mass.

As planets move around in space within their galaxy, they often orbit a star; just as our earth orbits solar star, our sun, in our solar system.

Sometimes, one or more smaller planets may orbit a bigger planet. When this happens, the smaller planets are called moons.

When planets orbit a star, and when moons orbit a planet, their respective gravities pull on each other, causing movement in their cores. That movement results in friction, which causes heat.

Thus, the formation of planets and moons around stars, all moving around in their orbits, creates heat within the different planets and moons. When there is underground water, that heat can cause steam. Even where there is no water, the heat can be so intense it can melt rock, causing volcanoes. Additionally, the central star in a planetary system radiates heat to the surface of its planets and moons, providing additional heat — and most importantly, light for plants to turn various elements into plant food in a chemical process called photosynthesis. Thus, light radiated from a star is necessary for plants to live.

And plants — like tomatoes and carrots and potatoes — are essential as food for animals, including humans like us, to live.

But so far, there were no plants, much less animals.

After about 13 billion years of the universe expanding and cooling — a little over half a million years ago, the first single-cell organisms formed in the seas. These were the precursors of invertebrates and algae.

But true plants require sunlight to grow. And there was no sun until the next epoch. So, no fully developed plants could develop until the planets settled into a regular orbit around a star so that there could be regular seasons for planting and harvesting as the planet circled the star once every year; and an earthly day and night as our planet spins on its axis once every day.

When our spinning earth settled into orbit around our sun and the moon settled into orbit around our earth, for the first time our earth had a sun during the day and a moon to reflect the sun's light to us at night.

This was the third cosmic ërꞋëv followed by cosmic morning: defining the third cosmic yom of our universe.