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Garments Sterilization Assay
clean room garments
sterilization
assay

When the Europeans conquered a "new world" they brought all their knowledge and technology together with their diseases. These diseases killed many people. Now that humans are ready to travel to other planets in search of life, we must ask, "have we learned our lesson?"
Planetary protection is a new field that is trying to answer this question and others, such as:

  • How can we protect other worlds from microorganisms found on Earth?
  • How can we protect other bodies from forward contamination?
  • How can we protect Earth from backward contamination?

First of all, when we are searching for extraterrestrial life we don't want to falsely register some Earth microbe incidentally left on the spacecraft as an "extraterrestrial microorganism". Second and most important, we have to be aware of the deadly consequences that contamination may have. Microorganisms from Earth could colonize the planets we visit. These foreign microorganisms could harm, change or even kill the indigenous planetary life.
Forward contamination is a term used to describe the transmission of microorganisms from Earth to other planets. Microorganisms from Earth could infect another planet, harming existing life on that planet or "seeding" a lifeless planet with microorganisms from Earth. If the life on the other planets is completely different from what we know on here on Earth, protection from possible contamination will be challenging because we won't immediately know how the extraterrestrial life is harmed.
NASA scientists are aware of the possibility of contamination and do their best to prevent contamination. All spacecraft are built in clean rooms in which workers wear gloves and booties, and where air vents suck up airborne microorganisms.
Everything is sterilized with an alcohol solution and the room is sealed from outside air.
Backwards contamination is the introduction of extraterrestrial microorganisms to Earth. Bringing back to Earth samples from planets, moons and other bodies is very exciting but should be treated with caution.
Samples should be sealed and carried in special containers. They must be under quarantine and carefully examined in specially sealed facilities before they can be released for further scientific analysis.
The need for backward planetary protection first arose after the lunar landings. Astronauts were dressed with biological isolation garments and were quarantined in a special sealed facility after their flight to the Moon.
Tree silhouette

Ecology is the study of interactions between living organisms and their environment. Currently studies are focused the ecosystems and biospheres of the Earth. However, eventual discovery of extraterrestrial life will change our understanding of ecology and new fields of study will emerge.

Temperature gauge

Vikings 1 and 2, the spacecrafts that first landed on Mars, were "cleaned" before their mission. They were sterilized and then "baked" at very high temperature at 110 C/230 F about 30 hours.

The Stardust spacecraft

The spacecraft Stardust returned comet samples to Earth. A soft substance called aerogel was used to catch some of the dust and gas particles from the comet. These particles were put in a reentry capsule, which parachuted to the Utah desert. After that it was transported in a special container to the Stardust clean room in Houston, where it has been carefully examined.

Eccentric Orbit

An orbit that's elliptical, deviating from circular.
The orange planet has an eccentric orbit, while the blue planet's is circular.

Meteor

Seen as a bright streak in the sky (sometimes called a shooting star or falling star) it is a tiny grain of dust or pebble that burns up when it hits Earth's atmosphere and crashes into Earth.

Atmosphere

The gaseous material surrounding planets; the air that surrounds Earth.

Helium

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Hydrogen

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Gravity

One of the fundamental forces of physics; gravitational attraction is responsible for the attraction of bodies on the surface of a planet to the mass of the planet.

Mass

The amount of matter in an object, measured in kilograms.

Solar Wind

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Orbital Resonance

The condition resulting from a two-planet or satellite system where one orbital period is twice that of the other. Resonances are possible with more than two planets; three of the Galilean satellites of Jupiter are in 1:2:4 resonances with each other.

Temperature

As a point of reference for the night (-275° F) and day (840° F) temperatures on Mercury, water freezes at 32° F and boils at 212° F, at 350° F you can bake a pie in your oven and a 90° F day can be considered a hot summer day for many of us on Earth.