NAI Team: We protect the Earth’s atmosphere.
Adrian lives on the planet Earth. His cousins, 98 Ianthe and 431 Nephele, are asteroids and live in the main asteroid belt. This belt is farther from the Sun than the Earth is. The planet where Adrian lives (Earth) is covered by a very thin layer of gas, the atmosphere, as shown in the photograph.
One day, all three cousins meet together on Earth to catch up.
98 Ianthe and 431 Nefeli came from the asteroid belt. After taking off their protective suits, 98 Ianthe says with curiosity and a hint of annoyance:
98 Ianthe: Why do we even need the atmosphere?
431 Nephele: Do we need it to survive?
Adrian: Not you two. I do. I need to breathe oxygen. If I close my nose and mouth, I can’t last more than 1 minute without getting oxygen. I can close my nose for a while when I dive into the sea. My whole body needs the oxygen I get when I breathe. You are lucky. You don’t need oxygen. So you can make longer dives!
The special suits worn by Ianthe and Nephele prevent them from igniting when entering Earth’s atmosphere. Similarly, space shuttles also have similar protection when returning to Earth after a visit to the International Space Station, for example.
If 98 Ianthe and 431 Nephele, as well as the space shuttle, didn’t have the special protection, they would burn up upon re-entry into Earth’s atmosphere, just like shooting stars.
Looks like we’re in for a surprise! What happened? They all take a comfortable chair, line them up, each thinking of a wish, and sit there with their eyes closed, waiting for a shooting star to appear. Any object that heads towards Earth and doesn’t burn up in its atmosphere due to friction will fall to its surface, creating craters that indicate points of impact.
Exactly what happened on the surface of Mercury. It has an extremely thin atmosphere. It is so thin that it cannot completely burn up all the objects heading towards its surface. The result is that collisions occur, and the surface becomes filled with craters.
431 Nephele: Exactly, Adrian. Did you understand why we need to wear our special suits when we come to visit you on Earth?
98 Ianthe: And to wear a parachute? We don’t want to become craters too!
Adrianos: You’re doing the right thing, girls. If there was no atmosphere, you wouldn’t hear me now. Nor would I. Exactly. The atmosphere plays a crucial role in transmitting sound waves, allowing us to communicate effectively.
98 Ianthe: It’s not just that, birds fly because there is an atmosphere.
431 Nephele: And airplanes too!
Adrian: Also, the atmosphere absorbs the ultraviolet radiation coming from the Sun.
431 Nephele: Adrian needs to use sunscreen with only SPF 50 because he has the atmosphere to protect him.
98 Ianthe: But we, don’t have an atmosphere. We need to be careful not to get sunburned, to apply sunscreen with an SPF of 300, which is very expensive and hard to find.
Adrian: Well done! We discovered together many benefits of the atmosphere for humans on Earth.
98 Ianthe: Don’t forget that flowers and plants also benefit from the existence of the atmosphere.
431 Nephele: The atmosphere contains carbon dioxide that plants need to survive.
98 Ianthe: Also, many plants propagate through the air, and without the atmosphere, you wouldn’t have air to blow.
431 Nephele: So, humans wouldn’t even have food on a planet without an atmosphere.
Adrian: Don’t forget that it also keeps us warm.
Indeed, as shown in the photograph, a portion of the sunlight is trapped within the atmosphere. After multiple reflections, particularly when the atmosphere contains carbon dioxide (CO2), light is converted into heat, warming the Earth. If the atmosphere contains a high concentration of carbon dioxide, sunlight heat gets trapped, and it cannot escape. The result is that the temperature rises to excessively high levels.
Indeed, such a scenario may have occurred on the planet Venus. Venus exhibits the most intense greenhouse effect of all the planets in our solar system. Its atmosphere is 50 times denser than Earth’s, consisting mainly of CO2, and its temperature can reach up to 400 degrees Celsius. Modern studies indicate that billions of years ago, Venus’ atmosphere was similar to that of Earth. It’s possible that it had water in liquid form. It appears that this water boiled away and was lost.
431 Nephele: This happened mainly because gases that worsen global warming, such as CO2, increased significantly.
98 Ianthe: Remember that, Adrian, since you live on Earth. You don’t want Earth to become like Venus! Do you?
If the temperature and the lack of oxygen were not a problem, nobody would be able to walk on the surface of Venus due to the high density of its atmosphere.
Adrian: Girls, when you come to visit me on Earth, you need to be careful not to end up falling into Venus instead of Earth. It’s the neighboring planet, closer to the Sun.
Venus is Earth’s twin sister.
Look here at the table comparing some of their characteristics.
Adrian: Let’s now focus on another planet in our solar system that doesn’t have an atmosphere, the planet Mars. Mars lost its atmosphere. Without an atmosphere, its temperature cannot stabilize, ranging from 20°C (midday at the equator) to -150°C (at the poles). Also, without an atmosphere, it cannot retain CO2, which is necessary for the planet’s warming.
431 Nephele: So, the atmosphere is the most precious thing a planet can have.
98 Ianthe: From what we understand, if its atmosphere is lost, Earth will become like Mars, which is both very cold and very hot.
Adrian: Don’t forget, girls, that Mars also lost its oceans without an atmosphere!
431 Nephele: We also don’t want the Earth, where you live, cousin, to become like Venus or Mars!
98 Ianthe: We don’t want it to become too hot, for the ice caps to melt at the North Pole, and for the polar bears to have nowhere to go.
Adrian: We should stop this overheating. I have seen on Earth’s television the ice at the North Pole melting and polar bears and their cubs having nowhere to go.
98 Ianthe: We heard that we need to stop burning fossil fuels (such as oil, natural gas, and coal).
431 Nephele: There’s no need, for example, to drive our cars to our French classes. Biking is better.
98 Ianthe: We also exercise to stay fit.
Adrian: I have a good idea on how to reduce carbon dioxide emissions that pollute the atmosphere. We should use batteries made from lemons instead of burning charcoal. I had once made a battery from a potato. A clock was connected as shown in the photo, and it was working.
98 Ianthe: Great idea, Adrian.
431 Nephele: Let’s finally do something to help the Earth’s atmosphere.
Adrian: No one on Earth cares about polar bears.
98 Ianthe: Tomorrow we will start working to build the battery.
431 Nephele: Let’s go rest now because we have a lot of work waiting for us tomorrow.