Jagatheesh is a Mechanical Engineer and interested in writing on science and technology in our life.
A Space station is a complex assembly of modules orbiting the planet earth at high speed. It doesn't have any propulsion or landing system. It works on the concept of orbital velocity, maintaining the balance between inertia and gravity. The same principle keeps the planets intact in their orbit around the sun. This article will explain the history and science of space stations.
What is a Space Station?
Space stations are a lab in the sky to conduct space exploration and researches. They are the complex assembly of various modules assembled over different time periods. As of 2021, there is only one fully operational space station working in the sky. Its main objective is to study the effect of space on humans.
The International Space Station, the only working space station, is revolving earth in Low Earth Orbit. It orbits at an altitude of around 240 miles from the earth's surface. Researches in ISS will provide valuable inputs to explore the space beyond the Low Earth orbit. Countries around the world are planning to build their own space station.
Basic Space Vocabulary
These are the few concepts to know before we read about Space ships.
- Orbit: An orbit is a regular, repeating, path of a satellite around a celestial body.
- Orbital Velocity: It is the speed required by an object to remain in an orbit of a celestial body. The object's velocity should overcome the gravitational pull of the celestial body and align with its rotational velocity.
- Gravitational Pull: The gravity of an object is the force that pulls the smaller object towards its center. It is the force responsible for planets to revolve around the sun.
- Escape Velocity: It is the minimum speed required by an object to move away from the gravitational influence of a large body.
- Controlled Re-entry: It is the forced re-entry of an artificial satellite over a pre-determined area. It is one of the ways to remove the retired satellites from orbit. The objects re forced to enter the earth's atmosphere where it burns due to the friction with the atmosphere.
- Disposal Orbit: It is the orbit that lies away from the operational orbits. It is also known as graveyard orbit.
Architecture of a Space station
The space stations are the complex assemblage of various modules. In the initial days of space exploration, a single module is launched to perform researches. In later stages, two or more modules are launched independently and assembled in space.
The assembly of the International space station begins in 1998. It is like building a house when we are living inside.
Major Components in a Space Station
A space station has various components assembled to form a complete structure.
- Pressurized Modules: These are the areas where astronauts live and work. They are shaped like canisters and spheres. It has living quarters and laboratories.
- Nodes: These are the connecting elements between various modules. They allow the astronauts and equipment to pass to other station areas.
- Docking Ports: They are used to attach various vehicles launched at different periods of time to ISS.
- Integrated Truss Structure: It is the backbone of a space station. It is made up of many triangular structures and beams. Solar panels and radiators are attached here. It maintains the temperature of the space station.
- Remote Manipulator System: It is the robotic arm of the space station. It helps to construct the station by moving the modules. They are also used to retrieve cargo from the shuttle bay.
- External Research and Payload Accommodation: It provides multiple mounting locations outside a space station for the experiments conducted outside the facility.
Jeff Bezos announced that he, along with two other people, is going to space on July 20, 2021. It marks the new beginning in the Space tourism
Launching a Space Station
Johannes Kepler introduced the concept of orbital velocity to the modern world. It is the same law that keeps the moon revolving around the earth. The planets revolve around the sun due to the orbital velocity achieved by the planets. When the orbital velocity is low, the object will be attracted by gravity. When orbital velocity is high, it escapes the orbit and enters into space.
The Space Station is a complex assemblage of machinery. Rockets are used to launch different modules. When a rocket is launched, it takes the modules to a particular altitude. Then it travels in the orbit parallel to the earth. The modules are released from the rocket when it reaches the required orbital velocity.
At orbital velocity, the modules travel around the earth without any propulsion. But due to the friction caused by the air molecules, the space station loses its altitude. To adjust the altitude, the space station uses a propulsion system. International Space Station loses 90Metres every day due to atmospheric interference.
How Does the International Space Station Works?
International Space Station travels at a speed of 17500 miles per hour at an average altitude of 250 miles. The ISS orbits the planet earth 16 times in a day. Various experiments in the field of Biology, fundamental physics, material sciences are studied in ISS.
The Space station gets a majority of its electricity from the solar panels. The energy is stored in lithium-ion batteries. The service modules and supply ships boost the propulsion for altitude adjustment and to avoid debris. The astronauts in the space station communicate through the tracking and data relay satellites. They use GPS and the Russian satellite system to track the location.
Oxygen is supplied from the earth by spacecraft. ISS also has a system to generate oxygen using electrolysis. The crew entirely depends on supply from the earth for food. Most of the food arrives in a specially designed packet. 80% of water is recycled.
Microgravity is the major concern of the International Space Station. It is the condition in which the gravity is not strong enough to pull the objects. So everything in ISS floats. In microgravity, bones lose calcium, and muscle loses mass(Osteoporosis). The astronauts have to do regular workouts to stay strong and avoid osteoporosis. They are equipped with a customized treadmill, an exercise bike, and a weight lifting device.
"The thing I'll remember most about the flight is that it was fun. In fact, I'm sure it was the most fun that I'll ever have in my life."
— - Sally K. Ride, First Woman to Orbit Earth on the Space Shuttle
Decommissioning a Space Station
The satellites and space stations are designed to work for a particular period of time. When the satellites performed their work, they are decommissioned either by controlled re-entry or by pushing them into a disposal orbit. Around 3000 dead satellites are orbiting the earth.
Check this Video for the Tour of International Space Station
Future of Space Stations
The Space Stations are truly an engineering wonder that humans can ever build. With the advent of corporations in space exploration, curiosity is increasing every day. When the scientific community works together, it is not so hard to travel in space beyond Low Earth Orbit. Well, let's wait to travel in space to confirm the presence of Aliens on other planets.
- What is Microgravity?, February 15, 2012. NASA, Accessed June 2, 2021
- Sandra Magnus Journal, October 2010. NASA, Accessed June 2, 2021
- International Space Station Basics, NASA, Accessed June 2, 2021
- Microgravity and ISS, The European Space Agency, Accessed June 2, 2021
- How the International Space Station Works? February 5, 2021, Accessed June 2, 2021
- About Research in Space, The European Space Agency, Accessed June 3, 2021
- The Space Flight Environment: The International Space Station and Beyond, National Centre for Biotechnology Information June 9, 2009, Accessed June 3, 2021
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2021 Jagatheesh Aruchami