I looked at the screen; it didn’t change, and it wasn’t wrong.  While the information was somewhat surprising, the experiences I had had in my time in Equestria had begun to make more and more sense.  Human tools were used here because they predated Equestria; human customs and holidays had existed as well, but had evolved into versions that ponies now used today.  

Twilight looked up at the monitor, “I never knew that we were a part of a solar system so large,” her voice and face completely awash with her awe, “This is amazing!  Look, there's the red planet Aithon, the horse of Strife.  And there, the other planet is Aphrodite, the alicorn of passion and affection!”  She looked to the Doctor, “but what do you mean this is Earth?  That’s the name of Adam’s home.”  

“This is Adam’s home.  You live on an alternate version of Adam’s home planet.  I’ve dealt with parallel dimensions before; time must flow at a different rate in this parallel stream, and it appears we are chronally displaced because of the accelerated rate of this universe's passage of time over mine and Adam’s universe.”  

“What?”  Twilight asked.  

Ditzy Doo looked at her and shrugged, “Wibbly Wobbly Timey Wimey”.  

“Wait, wait, wait,” I shook my arm and stub and pointed with my right index finger at the Doctor, “If this is Earth, then where’s the Sun?”  I pointed to the screen, and sure enough, there was no Sun around which the rings and planets were orbiting, just a blank spot.  “And what are these things?”  I pointed to two smaller objects orbiting the third ring’s planet.  Two spheres were lazily rotating around that planet.  “I guess one is the moon, but what is the other thing?  We should be able to see it from anywhere.”  

The Doctor looked at me with a grin, the infuriating grin that plainly says, ‘I know something you don’t’.  “Here’s the weird thing: the Sun as you knew it is not there anymore, but we are still orbiting something even if we can’t see it.  If you were to look through the right instruments, you would see sporadic spikes of x-rays coming from this region,” the Doctor pointed to the center of the image.  “The Sun still exists, but it’s a Brown Dwarf.”  

“How can the Sun be short,” Rainbow Dash asked with frustration, “what does that even mean?”  

“In the life span of a star,” the Doctor explained, “one of the last stages of its long life is what’s called a Brown Dwarf.  The Sun collapses in on itself and it can no longer be seen because it doesn’t emit visible light.  But that takes billions of years to occur.  We must be almost 17 billion years in the future from the time Adam and I came from.”  

“If that’s true; that the Sun has burnt out,” I pointed to the ceiling of the Tardis, “What would be hanging over us right now if it were daytime?”  

“A secondary star, much closer to Earth.  This is brilliant!  Somehow, a second, younger Sun is orbiting Earth, and I have no idea how it got there!”  The Doctor shook his hands in excitement, “I love mysteries!”