Question
Gayatri mantra and three Lokas (planes)
Answer
Looks like I got the answer to my old question. Here is quote from Bhagavata (5.20.37)
By the supreme will of Krishna, the mountain known as Lokāloka has been installed as the outer border of the three worlds—Bhūrloka, Bhuvarloka and Svarloka—to control the rays of the sun throughout the universe.
All the luminaries, from the sun up to Dhruvaloka, distribute their rays throughout the three worlds, but only within the boundary formed by this mountain. Because it is extremely high, extending even higher than Dhruvaloka, it blocks the rays of the luminaries, which therefore can never extend beyond it.
So it is very clear. Sun rays goes only upto svarga loka. Lokaloka mountain blocks the sun rays from going up further.
Gayatri mantra is very right in mentioning only earth,bhuvar,svarga loka as lokas sun rays would reach.
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