For me, Pure Lands are Reward Lands, created by pure vows and pure merits of the Buddha’s. This is in direct opposition of Impure Lands, created by our impure karma and with flawed merits and virtues contributed by all sentient beings there. Impure Lands are part of Samsara, and of Triple Realm, this mean, every place in the universe, including other planes like heavens and hells. So for me, does not matter if we go to the end of the universe or multiverse, there is samsara too.
Pure Lands are Nirvana realms, created by the Buddha’s.
When I read sutras like Vimalakirti, of purifying our own land, I take this as a mental purification, because even when we have pure minds, these lands will continue to be part of samsara, subject to birth and death. So, when we say that Maitreya will establish his pure land here on Earth, is just a better place to live, better teachings and conditions, but still part of samsara and triple realm, because this land is created by our own karma, not Buddha’s vows and merits.
So, for me, Pure Lands are Reward Lands, while our Impure Lands are Defiled Lands, Transformation Lands. Buddha’s come to these impure worlds to save sentient beings and to purify us.
So, for me, science can only know everything that is part of samsara and triple world, like our universe, but not nirvana realms like Pure Lands.
Interpreting all universe as part of samsara and triple world is also confirmed by Josho Adrian Cirlea, who kindle said to me:
No, we cannot go to the Pure Land by a space ship because the Pure Land is not part of the Samsara and the physical material unverse we know is part of samsara, too. Other worlds with many planets and solar systems are also part of the endless Samsara, the world of birth and death. The Pure Land is beyond Samsara, it is not samsara, its the manifestation of Amida Buddha's Enlightenment and of his wish to save all beings.
So, taking pure lands outside of our universe, making them Sambhogakaya Realms, or Nirvana Realms, I can fully accept it and understand it better.