I was going to add to those spotting the risk of contamination but then realized my error.  This is an accurate model.   The earth wasn&#x27;t a sealed environment.  The earth was and is constantly bombarded by foreign substances.  Not a month goes by that I&#x27;m not reading about some new organic chemistry in space.<p>That face on mars shows us that life most certainly was brought to earth from elsewhere.  So if this machine is contaminated by some student&#x27;s dandruff then it&#x27;s only all the more accurate a simulation.