Now, my friend, you can easily apply a scientific theory in explanation of these strange facts of which I was witness. If from the Earth one sees the star Capella, not as it is at the moment of observation, but as it was seventy-two years before, in the same way from Capella one would see the Earth as it was seventy-two years earlier, for light takes the same time to traverse the distance either way.
Quærens. Master, I have followed your explanation attentively. But, I ask you, does the Earth shine like a star? Surely she is not luminous?
The other planets seen from afar.
Lumen. She reflects in space the light of the Sun; the greater the distance the more our planet resembles a star. All the light that radiates from the Sun on its surface is condensed into a disc that becomes smaller and smaller. Seen from the Moon our Earth appears fourteen times more luminous than the full Moon, because she is fourteen times larger than the Moon. Seen from the planet Venus the Earth appears as bright as Jupiter appears to us. From the planet Mars the Earth is the morning and the evening star, presenting phases like those of Venus to us. Thus, although our Earth is not luminous herself, she shines afar like the Moon and the planets, by the light that she receives from the Sun, and reflects into space.
Now the events taking place on Neptune, if seen from the Earth, would have a delay of four hours; in like manner the view of life on the Earth could only reach Neptune in the same time; nearly seventy-two years, therefore, separate Capella and the Earth.
Quærens. Although these views are new and strange to me, I now understand perfectly how, since the light was nearly seventy-two years in traversing the abyss which separates the Earth from Capella, you beheld not the Earth as it was in October 1864, the date of your death, but as it appeared in January 1793. And I comprehend quite as clearly that what you saw was neither a phenomenon of memory, nor a supernatural experience, but an actual, positive, and incontestable fact, and that in very truth what had long passed away on the Earth was only then present to an observer at that distance. But permit me to ask you an incidental question. In coming from the Earth to Capella did you cross that distance even more quickly than light?
Thought swifter than light.
Lumen. Have I not already anticipated your question in telling you that I crossed this distance with the swiftness of thought. On the very day of my death I found myself on this star, which I had admired and loved so much all my life on the terrestrial globe.
Quærens. Ah, Master, although everything is thus explained, your vision is not the less wonderful. Truly it is an astonishing phenomenon that of seeing thus at once the past in the present in this extraordinary manner. Not less marvellous is the thought of seeing the stars, not such as they are when one makes the observation, nor as they have been simultaneously, but as they have been at different epochs according to their distances, and the time that the light of each has taken in coming to the Earth!
Light.