Science & Technology
Risk of Interplanetary Contamination on Mars
- 28 Jul 2020
- 5 min read
Why in News
Recently, astrobiologists have expressed concerns about possible ‘interplanetary contamination’ on Mars as ambitious space missions are proliferating the space along with advances in commercial flight.
- Interplanetary contamination refers to biological contamination of a planetary body by a space probe or spacecraft, either deliberate or unintentional.
Key Points
- Context: In the past several missions have launched to Mars e.g. China’s Tianwen-1 which aims to land on the Red Planet’s surface, and the UAE’s Al Amal (Hope) which does not involve a landing, but an orbital mission that will study the Martian atmosphere.
- The USA will soon launch its Perseverance mission, which would be the National Aeronautics and Space Administration’s (NASA) 10th successful Mars landing since 1975.
- The Perseverance is a rover name for NASA’s Mars 2020 mission.
- It will seek signs of ancient life and collect rock and soil samples from the planet.
- In the past, space missions have established physical contact with astronomical bodies such as comets and asteroids, and crewed missions have landed on the Moon.
- However, since these bodies are known to be hostile to life, the possibility of their contamination has not been a pressing issue.
- The USA will soon launch its Perseverance mission, which would be the National Aeronautics and Space Administration’s (NASA) 10th successful Mars landing since 1975.
- Type of Contamination: There are two types of contamination i.e. forward and backward contamination.
- Forward Contamination: It means the transport of Earth-based microbes to other celestial bodies.
- Since, presence of liquid water was already discovered on Mars there is a chance that Mars has life and it is an ethical obligation on humanity to ensure that microbes from Earth do not disturb a possible Martian biosphere, allowing it to evolve in its own way.
- Secondly, Earth-based organisms could spoil the integrity of the Red Planet’s samples that rovers want to study – a highly disruptive concept for scientists who are looking for signs of native Martian life.
- Back Contamination: It is the transfer of extraterrestrial organisms (if they exist) into the Earth’s biosphere.
- The scientists rule out back contamination with respect to Mars sample-return mission as their biochemistry would be markedly different from that on Earth.
- Forward Contamination: It means the transport of Earth-based microbes to other celestial bodies.
- Planetary Protection:
- United Nations Outer Space Treaty of 1967: It serves as a defence mechanism against the militarisation of space and also requires nations to worry about contamination risks.
- Its 110 state parties include the USA, Russia, China, and India.
- To ensure compliance with the Treaty, the Committee on Space Research (COSPAR) lays down a ‘planetary protection policy’ that aims to limit the number of microbes sent to other planets, as well as ensuring that alien life does not cause havoc on Earth.
- United Nations Outer Space Treaty of 1967: It serves as a defence mechanism against the militarisation of space and also requires nations to worry about contamination risks.
- Impact of the Policy: The guidelines have had far-reaching implications on human spacecraft design, operational procedures, and overall mission structure.
- Both NASA and the European Space Agency (ESA) have also appointed Planetary Protection Officers.
- Solutions:
- Spacecraft Sterilisation: To prevent forward contamination, space missions take care to ensure that spacecraft are sterilised.
- Previous Mars missions, such as NASA’s Viking landers of the 1970s, were all sterilised before being launched into space.
- NASA’s Perseverance mission was also postponed for a second time to resolve a potential contamination issue.
- Spacecraft Sterilisation: To prevent forward contamination, space missions take care to ensure that spacecraft are sterilised.
- Containment: In the case of back contamination, sterilisation would not be an option–as this would ruin the extraterrestrial samples.
- Containment would be the only option to break the chain of contact between possible alien microbes and life on Earth.
Way Forward
- In the present times nations have been fighting a race to get a strategic edge and compromising the ethical aspects of space technology. Therefore, it is important to acknowledge that space may not become purely a military domain due to weaponisation of the space.
- Space must be used only for peaceful purposes and any violation of Outer Space must not be tolerated.
- The natural biosphere of earth and other planetary bodies must be ensured through international cooperation.
