Originally posted by NemeBroThat's a sensory feat, not a reaction feat. Gorr reacted after seconds of them traveling. How that he was able to see detect them is irrelevant.
The key difference being that Gorr wasn't moving at those speeds, the Thors were, and that they are considerably smaller than the sun. You would need the ability to track two human-sized objects moving faster than the speed of light and react accordingly to their movements to hit them with an attack.
For future reference. Ftl reflexes is the ability to react in less than a nanosecond.