How fast is our galaxy moving

Much like all the planets in our Solar System, Earth orbits the Sun at a much speedier clip than its rotational speed. The inner planets — Mercury and Venus — move faster, while the outer worlds like Mars and beyond move slower than this.

The difference is severe: Mercury makes about 4 orbits for every 1 of Earth's, and it takes Neptune over Earth orbits before it's completed even one revolution. Moreover, as the planets orbit in the plane of the solar system, they change their direction-of-motion continuously, with Earth returning to its starting point after days. Well, almost to its same exact starting point. An accurate model of how the planets orbit the Sun, which then moves through the galaxy in a Note that the planets are all in the same plane, and are not dragging behind the Sun or forming a wake of any type.

Our Milky Way galaxy is huge, massive, and most importantly, is in motion. All the stars, planets, gas clouds, dust grains, black holes, dark matter and more move around inside of it, contributing to and affected by its net gravity.

From our vantage point, some 25, light years from the galactic center, the Sun speeds around in an ellipse, making a complete revolution once every — million years or so. Throughout it, though, the planets remain in the same plane, with no "dragging" or vortex patterns emerging. Although the Sun orbits within the plane of the Milky Way some 25,, light years from the But the galaxy itself isn't stationary, but rather moves due to the gravitational attraction of all the overdense matter clumps and, equally, due to the lack of gravitational attraction from all of the underdense regions.

Within our local group, we can measure our speed towards the largest, massive galaxy in our cosmic backyard: Andromeda. The largest galaxy in the Local Group, Andromeda, appears small and insignificant next to the Milky The Local Group, as massive as it is, isn't completely isolated.

The other galaxies and clusters of galaxies in our vicinity all pull on us, and even the more distant clumps of matter exert a gravitational force. And that explains part, but not all, of the large-scale motion through the Universe. There's also one more important effect at play, one that was quantified only recently: the gravitational repulsion of cosmic voids.

Buckle your seat belts, friends. The Sun, Earth, and the entire solar system also are in motion, orbiting the center of the Milky Way at a blazing miles a second. Even at this great speed, though, our planetary neighborhood still takes about million years to make one complete orbit -- a testament to the vast size of our home galaxy. Dizzy yet? Thus, the surface of the earth at the equator moves at a speed of meters per second--or roughly 1, miles per hour.

As schoolchildren, we learn that the earth is moving about our sun in a very nearly circular orbit. It covers this route at a speed of nearly 30 kilometers per second, or 67, miles per hour.

In addition, our solar system--Earth and all--whirls around the center of our galaxy at some kilometers per second, or , miles per hour. As we consider increasingly large size scales, the speeds involved become absolutely huge!

The galaxies in our neighborhood are also rushing at a speed of nearly 1, kilometers per second towards a structure called the Great Attractor, a region of space roughly million light-years one light year is about six trillion miles away from us. This Great Attractor, having a mass quadrillion times greater than our sun and span of million light-years, is made of both the visible matter that we can see along with the so-called dark matter that we cannot see. Each of the motions described above were given relative to some structure.

Our motion about our sun was described relative to our sun, while the motion of our local group of galaxies was described as toward the Great Attractor. Most certainly not! That's the cosmic story of structure formation, taking place within the expanding Universe.

So what does that mean out near us? It means our Milky Way is being pulled by all the other galaxies, groups and clusters in our vicinity. It means that the closest, most massive objects around are going to be the ones that dominate our motion, and that they have for the entire cosmic history.

But until we fully understand everything in the Universe that affects us, including:. At least, not without this one trick. You see, everywhere we look in space, we see this: the 2. This comes about because the Big Bang happened everywhere at once in space, Prior to that time, some , years after the Big Bang, it was too hot to form them, as photon collisions would immediately blast them apart, ionizing their components.

But as the Universe expanded and the light redshifted and lost energy , it eventually became cool enough to form these atoms after all. And when it did, those photons would simply travel, unimpeded, in a straight line until they finally ran into something.

Aside from those microkelvin imperfections, it should be uniform in all directions.