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Earth vs. Space
Image by NASA

     Imagine biting into a Granny Smith, or green, apple. As you bite into it, you can feel all the different tastes and textures. Just as you sink your teeth to pierce the apple’s skin, you can feel a satisfying crunch, followed by a gush of sour juices, but as you got deeper, you were exposed to a much different tone; a mellow, sweeter, and juicer taste in the inner flesh of the apple balances your palate. Even though these two features make up the same fruit, they both have completely different atmospheres. Similarly, even though Earth and space belong to the same universe, their atmosphere and environments are completely different.

Earth's Atmosphere

          Unique and forgiving are both words that describe our Earth. Being the only planet to lie in the Goldilocks Zone (or the zone around a star where the temperature allows for liquid water to exist) in our solar system, It is able to sustain life on its surface with liquid water. Earth’s atmosphere is also quite unique compared to other non-gas giant planets. Its atmosphere is mainly composed of 78% nitrogen, followed by 21% oxygen, 1% argon, and 0.04% carbon dioxide. Other planets, including Venus and Mars, nearly completely consist of carbon dioxide (approximately 95%). Earth’s atmosphere is divided into five layers: the exosphere, the thermosphere, the mesosphere, the stratosphere, and the troposphere. The furthest layer, the exosphere, is extremely thin, able to merge with outer space, comprised of hydrogen and helium. The thermosphere, from 90 km all the way to 500-100 km, is where the International Space Station orbits Earth. At this altitude, the temperature can reach an astonishing 1500℃. Below the thermosphere is the mesosphere which ranges from 50 km to 85 km above surface level. Completely opposite from the thermosphere, the mesosphere’s temperatures can be as low as -90℃. The second closest layer to Earth is the stratosphere which ranges from 20 km to 50 km above surface level. This level is where jets and weather balloons are flown due to the extremely thin air compared to the air at sea level, about a thousand times thinner. Along with this, ozone is abundant in this layer, heating the atmosphere while also absorbing harmful radiation waves given out from the sun. The closest layer to Earth’s surface is the troposphere, ranging from 7 km to 20 km above surface level. This is the altitude where clouds form as almost all water vapor and dust rises to the sky due to colder air going up and warmer air going down near the ground.

Space's Enviornment

          Unlike the Earth, temperatures in the space can largely vary. In space, depending on how far away you are from the sun, temperatures can be hundreds of degrees below freezing or hundreds of degrees above. The average temperature of space, however, is approximately 2.7 Kelvin. Along with this, the vacuum of space does not have an atmosphere, meaning that we would not be able to breathe in space. The lack of Earth's magnetic field and ozone layer causes the radiation within space to also be very dangerous. In space, you would be unable to hear anything that anyone would say. When on Earth, the sounds that you here are a result of sound waves traveling through a medium such as water or air. Since there are very few of these mediums within space in which sound can travel, it is hard to hear anything in space. On Earth, we usually have the force of gravity to keep our momentum from allowing us to fly away. However, gravity does not exist in space at the same magnitude in which it does on Earth. Therefore, any momentum that is obtained will be conserved until another external force from another object within space alters our motion. Many of these properties of space may sound fun, but space in and of itself does not meet the essential conditions in order for life as we know it to thrive within it. However, although space is not friendly for living organisms to inhabit, it is an important aspect of our universe that we will continue to study about. 

Sources: National Geographic Society. “Atmosphere.” National Geographic, National Geographic Society, 9 Sept. 2019, 


“Surviving Extreme Conditions in Space.” ESA, ESA, 27 July 2004, 

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