I was meditating on time today, precipitated by some things I have recently learned about the light of the Sun that reaches Earth.
I have long known that to look up into the night sky is to look far into the past. Looking up at the star Sirius, I am seeing 9 years into the past. Looking over at the star Antares, I am seeing 250 years into the past. And when I look the star Rigel, I am seeing 600 years into the past. Looking farther still at the Andromeda galaxy, I am seeing a million years into the past. That is how long it takes the light of these stars and galaxies to reach us! We are not seeing them as they are now, but as they were then. The past—even the distant past—is very present to us.
The light of the Sun takes 8.25 minutes to reach us. Thus we see its surface not as it is now, but as it was more than 8 minutes ago.
Yesterday, I learned that the light of the Sun is even older than I had thought. A little research on my part revealed this astonishing fact: the photons of light that reach the surface of the Sun (and then reach us 8+ minutes later) were actually generated 100,000 years ago in its core.
Emerging from the Sun’s core as the result of nuclear fusion, a photon of light enters the radiative zone. The plasma in that zone creates quite a maze for the photon to get through; it takes the better part of 100,000 years to make the journey to the convective zone and the photosphere where it finally begins a rapid journey out into the vacuum of space.
Why does it take this long? Imagine being in a large room filled with people, trying to get to the door on the other side the room. But as you try to make your way across the room, person after person strikes up a conversation with you, delaying your progress. It won’t take you 100,000 years to get to the door, but you get the idea.
Thus, the sunlight we currently bask in is much more than 8 minutes old; it’s actually 100,000 years old! The light we see today was made in the Sun’s core back during the beginning of the last ice age.
The great mystery of time is on display for us at every moment. The past is present in many ways. And our past is on display and still present as well. If anyone on a planet near Rigel were looking back through a telescope at Earth right now, he would not see us as we are today but as we were in the 15th century. The light of our “today” will not reach Rigel for 600 years.
What is the present? It depends on where you are. God, who is just as present at Rigel as He is here, has the same access to the images of 1417 as he does to those of 2017. Indeed, He is present at Andromeda just as much as here on Earth; and a million years ago is just as accessible to Him as is today.
The future is even more mysterious, but to God, the future is just as available as is the past.
Do not miss the irony of the fact that the light of the Sun (and the reflected light of the Moon), by which we measure the passage of time and tell what time it is now, is about 100,000 years old.
Does anybody really know what time it is? Only God, only God. Time is very mysterious. It seems that the more we think we know, the less we really do.
All the days ordained for me were written in your book before one of them came to be. How precious to me are your thoughts, God How vast is the sum of them! Were I to count them, they would outnumber the grains of sand—when I awake, I am still with you (Psalm 139:16-18).