Officially, Sputnik was launched to correspond with the International Geophysical Year, a solar period that the International Council of Scientific Unions declared would be ideal for the launching of artificial satellites to study Earth and the solar system. Sputnik was some 10 times the size of the first planned U. The U. The first U. By then, the Soviets had already achieved another ideological victory when they launched a dog into orbit aboard Sputnik 2.
The Soviet space program went on to achieve a series of other space firsts in the late s and early s: first man in space, first woman, first three men, first space walk, first spacecraft to impact the moon, first to orbit the moon, first to impact Venus, and first craft to soft-land on the moon.
But if you see something that doesn't look right, click here to contact us! Open golf tournament, edging Willie Dunn and others with a hole total of at the Newport Rhode Island Golf Club, an oceanside course. Rawlins worked at the Newport Golf Club as an assistant to The prosecutor in the case later was accused of withholding evidence indicating that Morton was innocent.
On the afternoon Skip to content. Photograph by Mark Thiessen, National Geographic. Twitter Facebook Pinterest Google Classroom. Background Info Vocabulary. Soviet Union. More Dates in History January. Media Credits The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
Media If a media asset is downloadable, a download button appears in the corner of the media viewer. Text Text on this page is printable and can be used according to our Terms of Service. Interactives Any interactives on this page can only be played while you are visiting our website. 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.
Such disaster is inevitable due to satellite drag , which is a way to quantify how much speed a satellite loses over time due to the atmospheric particles it runs into at high relative speeds. Any satellite in low-Earth orbit will have a lifespan ranging from a few months up to a few decades, but no longer than that. You can combat this by going to higher altitudes, but even that won't save you forever.
So, the satellite was quite small compared to the spacecraft of today, such as NASA's Cassini Saturn orbiter, which was about the size of a school bus. But lofting something as heavy as Sputnik 1 was quite a feat in October Two months later, the United States tried to launch its first satellite — the 3. Soviet space officials had wanted the nation's first satellite to be much bigger than a beach ball. The original plan called for lofting a nearly 3,lb. But development of this satellite, code-named "Object D," progressed more slowly than expected, and Soviet officials grew increasingly worried that the United States might beat them to space.
So, they decided to precede the launch of Object D with a "simplest satellite," or "prosteishy sputnik" in Russian. The literal translation of "sputnik," by the way, is "traveling companion. However, researchers did learn some things about Earth's atmosphere by studying the beep-beep-beep radio signals emitted by the satellite.
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