Ytdyklly

As far as I know, it isn't ethical to contaminate outer space with life from Earth, because then we will never be sure if life can actually grow there. However, I just read reports that the latest Chang'e-4 brings an entire ecosystem to the far side of the moon, with Arabidopsis plant seeds and even silkworms.

Is this okay? Even if it is contained within the machine and not spewed out? What danger is there of the plant material coming out of the machine and contaminating the moon?

tl;dr: There are "96 bags of poop, pee, and puke" on the Moon already!

The bags of waste are ecosystems for sure, but like the ones you mentioned, they are not going to remain alive for very long.

From Gizmodo's There's Poop on the Moon:

There is, however, scientific value to the things left behind. Astrobiologists, for instance, hope to one day inspect that half-century-old feces to see if the crap has undergone any genetic mutations while in space. Even more mundane gear on the moon's surface offer a unique perspective on how different materials hold up in extreme environments like the moon, where temperatures oscillate between minus 370-degrees to 250-degrees Fahrenheit.

What kinds of mundane gear, you wonder? Well, there's actually an entire website devoted to trash on the moon. However, here's a list of the more interesting and unusual items—aside from the 96 bags of poop, pee, and puke:

• More than 70 spacecraft


• 5 American flags, all of which are now white


• 12 pairs of boots


• An olive branch sculpture made of gold:


• "Several improvised javelins"


• Used wet wipes


• Space food wrappers


• 2 golf balls


• This gold-plated telescope that was the first tool used to make astronomical observations from the surface of another planetary body:


• A feather from Baggin, the official mascot of Air Force Academy


• A patch from the doomed Apollo 1 mission that never launched


• This silicon disc with goodwill messages from 73 world leaders:


• 12 Hasselbad cameras


• This photograph of Astronaut Charlie Duke's family from Apollo 16:


• Not to be repetitive or anything: 96 bags of poop, pee, and puke

Humans have already been to the Moon, and pretty much verified it is completely sterile. It isn't really an issue bringing plants to the Moon, it couldn't contaminate anything, as there is nothing there it could really affect. Besides, anything complex couldn't survive in a vacuum, and there's been plenty of bacteria that have been on the Moon from the Apollo missions to previous landers.

According to Jainism and some forms of Buddhism, the concept of Ahisma tell us that it not ethical to bring an ecosystem of living creatures to an environment that will almost assuredly kill them as a result of you bringing them there.

Ahinsā (Ahinsā) in Jainism is a fundamental principle forming the cornerstone of its ethics and doctrine. The term ahinsa means nonviolence, non-injury and absence of desire to harm any life forms.... Furthermore, the Jains extend the concept of ahinsa not only to humans but to all animals, plants, micro-organisms and all beings having life or life potential. All life is sacred and everything has a right to live fearlessly to its maximum potential. Living beings need not fear those who have taken the vow of ahinsa.

Emphasis mine. Whoever decided to put those organisms on the vessel did so either knowing it would harm them, or if not, at least were not able to be sure that it wouldn't hamper the creatures' maximum potential.

From the article linked:

so it’s unclear whether plants and worms will grow normally with the moon’s meager 17 percent gravity.

To the Jainist belief system, that was an unethical action.