[madgar]

> In relativistic terms, the photon leaving the Sun and arriving at the earth can be considered to be simultaneous.

You just constructed an argument that can be readily used to argue that all events are simultaneous. That should flip your internal bozo bit and help you see that the argument is not sound.

[random314]

> You just constructed an argument that can be readily used to argue that all events are simultaneous

No, I haven't. I have studied relativity in University, have you? Lol @bozobit

I will make the statement more rigorous.

"Let event A represent the emission of a photon. Let event B represent the arrival of a photon elsewhere. Event here refers to a unique location in space-time i.e (x,y,z,t). As per special relativity, you can always find a reference frame such that the time separation between A and B can be arbitrarily small. It can't be made exactly zero, but it can be made as close to zero as you wish to."

Use this formula to figure out the reference frame of interest.

https://en.wikipedia.org/wiki/Length_contraction

The speed of light is constant. So decrease/contract the length until the time required = distance/c is one second or less.

[eternalban]

If you feel like getting mystical about it, for a hypothetical Photonic Being all events are in fact simultaneous: It is always 'now' and per various mystic schools, that 'timelessness' is the actual meaning of 'Eternal'.