Have you ever seen videos of in space going on a \”spacewalk\”? If so, you know that they don\’t look like they\’re walking like they do on Earth. Instead, they sort of
around. Here on Earth, when you drop a ball it falls to the ground. That\’s because of the of. But in space, everything floats. Why is that? Could it be because there\’s no air in? Maybe it\’s because the laws of don\’t to outer space? Scientists will tell you that the laws of do in outer space, and it\’s not a lack of air that accounts for the of gravity. So what\’s going on here? Why isn\’t there any gravity in space? Those same scientists would actually be quick to correct your. Gravity is Бeven in space! So what accounts for that weightless feeling that astronauts in outer space? There are a couple of factors that it. Anything with creates gravity. The gravity generated by the Sun, Earth, the, and other planets stretches throughout outer space. However, the effect of that gravity decreases as distance increases. At extreme distances, the gravity exerted on a particular object might be almost zero, but it will never be completely absent. Distance alone doesn\’t account for the weightless feeling astronauts get, however. To feel like there is no gravity due to distance, the distance must be truly extreme. For example, at the of the, which is approximately 250 miles above Earth, Earth\’s pull is still about 90% of what it is at Earth\’s. The weightless feeling astronauts can be explained by their to the spaceship they\’re on.
Astronauts on spaceships in outer space are affected by gravity in the same way that their spaceships are. They are both orbiting Earth, which means they\’re sideways at the same time they\’re toward Earth. On Earth, astronauts feel the of gravity as weight, because Earth\’s prevents them from. In outer space, however, there is no ground to push against astronauts. As they and fall toward Earth at the same rate as their spaceship, astronauts feel weightless, as if there were no gravity. Gravity exists, even in outer space. It may be so small at great distances that it\’s almost. Closer to Earth, however, astronauts get that weightless feeling not because of the of gravity, but because they\’re at the same rate as their spaceship and there\’s no ground to stop their fall and create the sensation of weight. Astronauts and space tourists may rhapsodize about feeling weightless during spaceflight, but don\’t be fooled by the somewhat misleading term zero-gravity. Every object in space still feels the gravitational pull from other objects, including space travelers who imagine themselves free of Earth\’s gravitational shackles. Earth\’s gravity affects everything at or near the planet\’s surface. We feel the force of gravity on Earth through our mass, and that force also translates into a downward pull of 9. 8 meters per second squared (32 ft/s^2). That\’s why astronauts need powerful machines such as the space shuttle\’s main engines and twin boosters or the Russian Soyuz rockets to travel beyond Earth\’s immediate gravitational tug.
How to stay Gravity represents the mutual attraction between two objects, and the strength of that pull depends on both mass and the distance between the objects. Greater mass leads to a greater gravitational pull, as anyone who has fought to lose a few pounds knows firsthand. By contrast, greater distance leads to rapidly diminishing gravitational pull. But w here the space station roams, some 220 miles (354 km) up, the force of gravity is still about 90 percent what it is here on the surface. Earth\’s gravity is still pulling down on astronauts in orbit. A spacecraft or space station can counter Earth\’s downward pull by creating enough horizontal speed so that it continually slides sideways as it simultaneously falls toward the planet, creating an orbit. For instance, the space shuttle typically travels at a blistering 17,000 to 18,000 mph around the Earth to stay aloft. That continuous free fall around the planet gives astronauts the impression of being weightless. Huge objects with enormous mass can make their gravitational effects felt across much greater distances. The moon maintains a free-falling orbit around the Earth, and the Earth itself remains in orbit around the massive sun. Our sun contains over 99 percent of all mass in the solar system, which explains why its gravitational pull has managed to snag eight planets and a host of other objects. Jupiter, the largest planet in our solar system, has also flexed its gravitational muscle across vast distances of space by pulling in space rocks and other debris which might otherwise threaten Earth.
That has allowed Earth observers to also witness several spectacular impacts on the gas giant, such one that recently the size of the Pacific Ocean. Even asteroids and other smaller space rocks exert weak gravitational pull. And on the flipside, some scientists have proposed using the mere mass of spacecraft to act as that gently tug threatening space rocks out of Earth\’s path. Albert Einstein proposed another way to think about gravity in space. Consider if the 3-D universe was a flat, 2-D sheet. Each object in space acts like a ball that weighs down on the space-time fabric and creates a bulging pocket similar to a shallow depression in the ground. That curvature of space-time has an inward falling effect on the paths of other objects, and particularly on smaller passing objects. It\’s like having a sheet stretched between two people, and watching a marble roll down into the bulge created by a large ball sitting on the sheet. More massive objects such as black holes create bigger bulging pockets of space-time, while tiny objects such as a spacefaring human would barely represent a dent. So gravity may be everywhere in space, but that won\’t stop astronauts or others from describing the wonderful feeling of weightlessness. Sometimes the illusion of human experience speaks volumes more than strict scientific fact.