When we read "Power," we picture the speaker sitting on a porch, thoroughly engaged in a book about Marie Curie. When she reads about her death, she puts down the book, looks out the window at the world before her, and contemplates Curie's fascinating life (and tragic death).
You may picture a different setting for this poem. And the reason for this is that the poem pretty much takes place in what we like to think of as "head space." You know, in the imagination or mind? It's a contemplative poem; the speaker is really making a journey into Marie Curie in her mind, not in the outside world. It could be set in North Carolina, Tokyo, or Mars, and it would make no difference, because we are really in the speaker's thoughts and mind in "Power."