Earth has never returned to the same point in space, science account notes

As Earth orbits the Sun, it has never come back to exactly the same point in space. The science outreach account "Philosophy Of Physics" made the point in a social media post on 2 November, refining the familiar school picture of Earth moving in a closed circle around the Sun.

Motion around the galactic center

The Sun, together with Earth and the other planets, travels around the center of the Milky Way galaxy at about 230 kilometers per second, or 828,000 kilometers per hour. That is more than 18,000 kilometers every 80 seconds.

The Solar System is tilted at 60.2° to the galactic plane and crosses the galactic disc roughly every 30 million years, moving up and down. As a result, the planets' path through space is not a flat loop but an open, three-dimensional spiral.

The galactic year

One full orbit of the Sun around the galactic center takes about 230 million years, a period known as a galactic year. The last time the Sun was in the position it occupies today, the first dinosaurs were just beginning to appear on Earth.

The Sun formed about 4.6 billion years ago and has completed only 20 full laps since then. Earth itself, according to the source, has not returned to the same point in space in the past 4.5 billion years.