It's a best effort approach to minimize the risk of "contaminating" planets with Earth life. It applies to any spacecraft in interplanetary space, not just landers, because it's impossible to predict where an object that ends up in heliocentric orbit will end up, it could end up hitting another asteroid, planet, or moon.
It's a best effort approach to minimize the risk of "contaminating" planets with Earth life. It applies to any spacecraft in interplanetary space, not just landers, because it's impossible to predict where an object that ends up in heliocentric orbit will end up, it could end up hitting another asteroid, planet, or moon.