William Pickering L , James van Allen middle , and Werner von Braun right , were responsible for the satellite, the science instruments, and the rocket that launched Explorer 1, respectively. What happened to Sputnik wasn't unusual. In fact, this is what happens to most satellites if you launch them into low-Earth orbit and leave them there to fend for themselves.
With each orbit that goes by, the satellite will swing by apogee, where it reaches its maximum distance from Earth's surface, followed by perigee, where it makes its closest approach to Earth.
For low-Earth orbit, that typically means that satellites are a few hundred kilometers above the Earth's surface, even at their closest. Considering that we draw the line between Earth's atmosphere and outer space at an altitude of only kilometers 62 miles , it would seem, at least superficially, that these satellites would be firmly and eternally in space.
An uncontrolled re-entry, on the other hand, could cause large, massive chunks to land pretty much anywhere on Earth. Heavy, solid objects, like Hubble's primary mirror, could easily cause significant amounts of damage or even kill, depending on where those chunks landed.
But in reality the situation is far more complicated. The atmosphere doesn't have a sudden end, or an edge to it. That isn't how a gas works if it's made up of real particles. As you go to higher altitudes, the density of particles will continue to drop, but the different particles that are heated by collisions will move around at different speeds: some faster, some slower, but with a well-defined average velocity.
The higher up you go, the more likely you are to find particles that are more energetic, as it takes more energy to reach those extreme altitudes. But even though the density is extremely low at very high altitudes, it never drops to zero. The layers of Earth's atmosphere, as shown here to scale, go up far higher than the Every object in low-Earth orbit is subject to atmospheric drag at some level.
We've found atoms and molecules that remain gravitationally bound to Earth at altitudes up to 10, km 6, miles. The only reason we haven't gone beyond that point is that past 10, kilometers, the Earth's atmosphere is indistinguishable from the solar wind, with both consisting of tenuous, hot atoms and ionized particles.
But the next layer, the thermosphere, is incredibly diffuse. The troposphere orange , stratosphere white , and mesosphere blue are where the overwhelming But beyond that, air is still present, causing satellites to fall and eventually de-orbit if left alone.
While an atmospheric particle at sea level will travel a microscopic distance before colliding with another molecule, the thermosphere is so diffuse that a typical atom or molecule up there might travel for a kilometer or more before experiencing a collision.
Up in the thermosphere, it sure does seem like empty space if you're nothing but a tiny atom or molecule. After all, you rose up from Earth's atmosphere, you linger in this low-density abyss while at the peak of your parabolic orbit, and you slowly, eventually, fall back to your home planet under the force of its gravity.
New ones will have to be launched to replenish them on an ongoing basis. Each black dot in Although the space near Earth looks crowded, each dot is much larger than the satellite or debris it represents, and collisions are extremely rare. The successful launch came as a shock to experts and citizens in the United States , who had hoped that the United States would accomplish this scientific advancement first. The fact that the Soviets were successful fed fears that the U.
As a result, the launch of Sputnik served to intensify the arms race and raise Cold War tensions. During the s, both the United States and the Soviet Union were working to develop new technology. Both countries were also engaged in developing satellites as a part of a goal set by the International Council of Scientific Unions, which had called for the launch of satellite technology during late or Over the course of the decade, the United States tested several varieties of rockets and missiles, but all of these tests ended in failure.
The Soviet launch of the first Sputnik satellite was one accomplishment in a string of technological successes. Few in the United States had anticipated it, and even those who did were not aware of just how impressive it would be. Sputnik 1 Schools Wikipedia Selection. Coming at the height of the Cold War , the launching of Sputnik caught the West by surprise, and in the U.
Spacecraft design The satellite weighed about 83 kg pounds. The Sputnik 1 satellite was a The antennas looked like long "whiskers" pointing to one side.
It had two radio transmitters 20 and 40 MHz and is believed to have orbited Earth at a height of about km miles. Analysis of the radio signals was used to gather information about the electron density of the ionosphere. Temperature and pressure were encoded in the duration of radio beeps, indicating the satellite was not punctured by a meteorite. Sputnik 1 was launched by an R-7 rocket.
It incinerated upon re-entry on January 3, Sputnik was the first of several satellites in the Soviet Union 's Sputnik program , the majority of them successful. Sputnik 2 followed as the second satellite in orbit, also the first to carry an animal, the dog Laika.
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