Planet Earth’s motion through space isn’t just defined by our axial rotation or our motion around the Sun, but the Solar System’s motion through the galaxy, the Milky Way’s motion through the Local Group, and the Local Group’s motion through intergalactic space. Only with everything combined, and by comparing to the Big Bang’s leftover glow, can we arrive at a meaningful answer. (Credit: Jim slater307/Wikimedia Commons; background: ESO/S. Brunier)

How, exactly, does planet Earth move through the Universe?

The Solar System isn’t a vortex, but rather the sum of all our great cosmic motions. Here’s how we move through space.

Planet Earth isn’t at rest, but continuously moves through space.

This view of the Earth comes to us courtesy of NASA’s MESSENGER spacecraft, which had to perform flybys of Earth and Venus in order to lose enough energy to reach its ultimate destination: Mercury. The round, rotating Earth and its features are undeniable, as this rotation explains why Earth bulges at the center, is compressed at the poles, and has different equatorial and polar diameters. (Credit: NASA/MESSENGER)

The Earth rotates on its axis, spinning a full 360° with each passing day.

The effects of the Coriolis Force on a pendulum rotating at 45 degrees North latitude. Note that the pendulum takes two full rotations of Earth in order to make a single, complete rotation at this particular latitude; the rotation angle, just like the speed at Earth’s surface, is latitude-dependent.. (Credit: Cleon Teunissen / http://cleonis.nl)

That translates into an equatorial speed of ~1700 km/hr, dropping lower with increasing latitudes.

The Earth, moving in its orbit around the Sun and spinning on its axis, appears to make a closed, unchanging, elliptical orbit. If we look to a high-enough precision, however, we’ll find that our planet is actually spiraling away from the Sun by about 1.5 cm per year, and precesses in its orbit on timescales of tens of thousands of years. (Credit: Larry McNish/RASC Calgary)

Meanwhile, the Earth revolves around the Sun, with speeds ranging from 29.29 km/s to 30.29 km/s.

Just 800 years ago, perihelion and the winter solstice aligned. Due to the precession of Earth’s orbit, they are slowly drifting apart, completing a full cycle every 21,000 years. Over time, the Earth drifts slightly farther from the Sun, the precession period increases, and the eccentricity varies as well. (Credit: Greg Benson/Wikimedia Commons)