( ( ( ( Earth ( ( did n't ) ( have ( an atmosphere ) ) ) ) , ) ( then ( , ( ( when ( ( the moon ) ( ( was entirely ) ( within ( ( Earth 's ) shadow ) ) ) ) ) ( , ( ( the moon ) ( would ( would ( appear ( ( black and ) invisible ) ) ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (NNP Earth)) (VP (VBD did) (RB n't) (VP (VB have) (NP (DT an) (NN atmosphere))))) (, ,) (S (ADVP (RB then)) (, ,) (SBAR (WHADVP (WRB when)) (S (NP (DT the) (NN moon)) (VP (VBD was) (ADVP (RB entirely)) (PP (IN within) (NP (NP (NNP Earth) (POS 's)) (NN shadow)))))) (, ,) (NP (DT the) (NN moon)) (VP (MD would) (VP (MD would) (VP (VB appear) (ADJP (JJ black) (CC and) (JJ invisible)))))) (. .)))
Earth didn’t have an atmosphere, then, when the moon was entirely within Earth’s shadow, the moon would would appear black and invisible.
(ROOT (S (NP (CD One) (NN way) (SBAR (IN that) (S (NP (DT the) (NN moon)) (VP (VBZ is) (ADJP (JJ different) (PP (IN from) (NP (NN earth)))))))) (VP (VBZ is) (SBAR (IN that) (S (NP (DT the) (NN moon)) (VP (VBZ has) (NP (RB almost) (DT no) (NN atmosphere)))))) (. .)))