- #1
iflexit_1
- 5
- 0
Hello everyone! I'm new to the board, so thought I'd take a moment and introduce myself. I have a degree in Liberal Arts, but like so many of us, the first time I gazed upward on a dark night and wondered in amazement, I was hooked. I have enjoyed perusing so many of your contributions, and hope in some small way I will be able to add a bit of knowledge to the forum.
Now I pose a question. I understand that due to the accelerated expansion of space, that the edge of the observable universe is about 46 bly. Now, a galaxy omits a photon aproximately 13.7 billion years ago. Space is expanding, so the space traversed by the photon expands behind it during the trip. Consequently, by the time the photon reaches us, the galaxy is about three times further. My question is this. Even though the photon has been stretched, and the galaxy is at a greater distance than 13.7 bly, won't the galaxy we observe when the photon reaches us be the galaxy as it appeared when it first emitted the photon? At 46 bly, and space still expanding, we may never see the photons emitted at that distance. Correct? In fact, our galaxy at 46 bly may have long merged with other galaxies.
Now I pose a question. I understand that due to the accelerated expansion of space, that the edge of the observable universe is about 46 bly. Now, a galaxy omits a photon aproximately 13.7 billion years ago. Space is expanding, so the space traversed by the photon expands behind it during the trip. Consequently, by the time the photon reaches us, the galaxy is about three times further. My question is this. Even though the photon has been stretched, and the galaxy is at a greater distance than 13.7 bly, won't the galaxy we observe when the photon reaches us be the galaxy as it appeared when it first emitted the photon? At 46 bly, and space still expanding, we may never see the photons emitted at that distance. Correct? In fact, our galaxy at 46 bly may have long merged with other galaxies.