Some of the particles that collide with our planet can kick atmospheric particles into space, causing them to escape from Earth entirely.
A total of about 18, tons of material strikes our planet every year, taking approximately 3 days to travel from the Sun to the Earth. The planets move in the orbits that they do, stably, because of the conservation of angular With no way to gain or lose angular momentum, they remain in their elliptical orbits arbitrarily far into the future.
However, changes due to collisions from particles, gravitational forces from other planets, or the changing Sun's mass can not only push Earth to farther distances, but slower velocities. Although Earth's orbit undergoes periodic, oscillatory changes on various timescales, there are also While the changes in the shape of Earth's orbit are large compared to these long-term changes, the latter are cumulative, and hence, are important.
The Earth, on average, revolves around the Sun at a speed of approximately This actually varies slightly, since the Earth makes an elliptical orbit around the Sun: moving faster at perihelion nearest the Sun and slower at aphelion farthest from the Sun.
The difference is small, but computable. At our fastest, we move through space at With each year that goes by, the Earth slows down by approximately 3 nanometers-per-second over how quickly it was moving the prior year. Over the 4. When we place the known objects in the Solar System in order, four inner, rocky worlds and four, Yet every object that orbits the Sun is spiraling away from the massive center of our Solar System as it burns through its fuel and loses mass.
Although we haven't directly observed this migration, the predictions of physics are extremely clear. This same analysis applies very to our recent past as well as to our near-term future. But as we look to longer and longer timescales, and the very far future of our Solar System, we can identify three future effects that could change our orbit dramatically when they finally become important. And there are a few. Over time, the gravitational effects of the planets tugging on one another will potentially cause our orbits to become chaotic.
If that occurs, Earth's orbit could change significantly, possibly even hurling our planet into the Sun or ejecting it from the Solar System entirely.
This is the most unpredictable component of our planetary orbit. As the Sun becomes a true red giant, the Earth itself may be swallowed or engulfed, but will The Sun's outer layers will swell to more than times their present diameter, but the exact details of its evolution, and how those changes will affect the orbits of the planets, still have large uncertainties in them.
In addition, the Sun will evolve quickly towards the end of its life, ejecting large quantities of mass and swelling into a red giant.
The ultimate fate of Earth remains unknown. Space is huge, and even our immediate environment is gigantic. We are the third planet from the Sun, and the third of three inner planets, all of which are right next to the Sun compared to others. The picture below shows the planets in their orbits on the orbital plane. You have to look carefully to see our home. The four inner planets Mercury, Venus, Earth and Mars are in the tiny disk in the center, inside of Jupiter's orbit.
The planets are far from the Sun, travel huge distances in space, and take a long time to do so. Pluto takes almost years to go around the Sun completely and travels almost 23 billion miles to do so! The two are rushing toward each other at about 70 miles per second km per second. There is no chance that you'll be flung off to space right now, because the Earth's gravity is so strong compared to its spinning motion. This latter motion is called centripetal acceleration.
At its strongest point, which is at the equator, centripetal acceleration only counteracts Earth's gravity by about 0. In other words, you don't even notice it, although you will weigh slightly less at the equator than at the poles. NASA says the probability for Earth stopping its spin is " practically zero " for the next few billion years. Theoretically, however, if the Earth did stop moving suddenly, there would be an awful effect.
The atmosphere would still be moving at the original speed of the Earth's rotation. This means that everything would be swept off of land, including people, buildings and even trees, topsoil and rocks, NASA added. What if the process was more gradual? This is the more likely scenario over billions of years, NASA said, because the sun and the moon are tugging on Earth's spin.
That would give plenty of time for humans, animals and plants to get used to the change. By the laws of physics, the slowest the Earth could slow its spin would be 1 rotation every days. That situation is called "sun synchronous" and would force one side of our planet to always face the sun, and the other side to permanently face away.
By comparison: Earth's moon is already in an Earth-synchronous rotation where one side of the moon always faces us, and the other side opposite to us. But back to the no-spin scenario for a second: There would be some other weird effects if the Earth stopped spinning completely, NASA said. For one, the magnetic field would presumably disappear because it is thought to be generated in part by a spin. We'd lose our colorful auroras, and the Van Allen radiation belts surrounding Earth would probably disappear, too.
Then Earth would be naked against the fury of the sun. Every time it sent a coronal mass ejection charged particles toward Earth, it would hit the surface and bathe everything in radiation. Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community space.
Elizabeth Howell is a contributing writer for Space. She is the author or co-author of several books on space exploration. Elizabeth holds a Ph. She also holds a bachelor of journalism degree from Carleton University in Canada, where she began her space-writing career in Besides writing, Elizabeth teaches communications at the university and community college level, and for government training schools.
To see her latest projects, follow Elizabeth on Twitter at howellspace. Jump to: Earth's spin Earth orbits the sun Movement of the sun and galaxy If Earth stopped spinning Additional resources.
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