By Ashley Hall
Traveling to space is every kid’s dream. Something about being in a rocket moving faster than you could ever imagine, wearing a cool space suit, and seeing stars up close is so appealing; or maybe it’s the dream of tasting our cheesy moon. Whatever the reason is, when we grow up and learn more about space, we realize space isn’t as glamorous as we thought it to be when we were children. We learn that space travel takes a lot of preparation and patience. So before deciding to become an astronaut, you should consider some very important details such as how long it takes to travel space and very serious health conditions.
What is a rocket? The word ‘rocket’ can mean many different things. Most people think of a tall, thin, round vehicle. They think of a rocket that launches into space. “Rocket” can also mean a type of engine or a vehicle that uses that engine. Whichever way you may think of rocket, they basically all work the same way; they all use Newton’s third law: for every action there is an equal and opposite reaction. The fuel pushes out fire and the force from the fire pushes the rocket upwards. As you can see in Figure 1, NASA’s space shuttle, Endeavor, follows this law.
One very important thing to know when traveling space is the distance from the starting point to the destination. For example, if you hitch a ride on Endeavor and take a ride to the Sun it will take you about 5357.1 hours, which is about 223.2 days. Endeavor travels at an average speed of 28,000 kilometers an hour and the Sun is about 150 million kilometers away, therefore equaling 5357.1 hours. But what about something farther? This time we will travel to the nearest star to our Sun which is Proxima Centauri. Proxima Centauri is about 39.9 billion kilometers away from Earth. Assuming we use Endeavor again, it will take about 142.5 million hours, which is about 59.375 million days or 160,000 years, to reach this star! Figure 2, below, shows the time it take to travel from Earth to different objects in space. Each dot refers to a different object in space; Mars, the Sun, Pluto, and Proxima Centauri. So you can see from the graph below that Mars will take less than a year to travel to, which is a very reasonable destination to travel to, unlike Proxima Centauri.
Mars is about 75314905.8 km away from Earth.
The Sun is about 150000000 km away from the Earth.
Pluto is about 5913520000 km away from the Earth.
Proxima Centauri is about 39900000000000 km away from the Earth.
Even though traveling to space may seem amazing, there are many health risks to be aware of before strapping on the seat belt of that cool rocket ship. Even though the Extravehicular Mobility Unit (EMU), also known as space suits, are made to keep the astronauts as safe as possible, there are many other factors that the space suit cannot help with. First of all, everyone knows there is no gravity in space, but what people don’t know is that the lack of gravity isn’t just the thrill of floating but it possesses many health challenges. Here on Earth, gravity pulls us down as well as all the fluids in our body. In space, those fluids are released from their gravitational pull and move upwards toward your head. When all the fluids reach your head it expands your face creating ‘puffy face’, and when the fluids escape your legs, your legs begin to shrink creating ‘bird legs’. Another health risk due to the lack of gravity is motion sickness. Motion sickness is caused when the brain and inner ear receive mixed signals. In a space shuttle the astronaut can obviously see what direction is up and which is down, but his or her inner ear cannot. On Earth, the sensors in the inner ear feel the gravitational pull, but without gravity the inner ear cannot detect which direction is which. A few other health risks include stress, loss of muscle mass, and radiation exposure.
So next time you dream about traveling to space, think about how long you are willing to be in a space shuttle and the many, many health risks you are likely to face.
1. Describe ‘puffy face’ and ‘bird legs’.
2. According to the data in Figure 2, how long will it take, in days, to travel from Earth to Pluto using Endeavor? Keep in mind that Pluto is about 5.91352 billion kilometers away from the Earth.
3. Explain Newton’s third law and how it is used for space travel.