540 sextillion miles.

Says modern science, meaning

5.4×10235.4 cross 10 to the 23rd power5.4×1023 or 540,000,000,000,000,000,000,000 miles.

Modern science assumes the universe three dimensional. However, the Vedas brings in the multidimensional universe , so the measurement of the Vedic universe incorporates things near and yet far , certainly there are red shift anomalies in the calculations of modern science,  as Sadaputa prabhu,  of Dr Richard Thompson mentioned in his book  on Vedic cosmology pointed out , are the stars so far away , on one level maybe , on another level not .

For instance, only 800 miles above this planet, an  Upadeva planet exist in their particular dimension.

The greatly renowned Vedic cosmological scholar in Gaudiya Vaisnavism says this ..

“Srila Bhaktisiddhanta Saraswati Goswami Thakura, recognized as a master of both Siddhantic Vedic astronomy and Puranic literature, provided specific measurements regarding the size of the universe based on classical Vedic texts

. He maintained that the universe is vast, egg-shaped (brahmanda), and, while immense, is only one of innumerable universes in the material creation. 

Measurements and Structure 

• Circumference: Citing the Siddhanta-siromani, Srila Bhaktisiddhanta Saraswati gave the circumference of this universe as 18,712,069,200,000,000×818 comma 712 comma 069 comma 200 comma 000 comma 000 cross 818,712,069,200,000,000×8 miles.
• Diameter: The inner part of the universe is described as having a diameter of approximately 5,956,200 crore yojanas (roughly 47,649,600 billion miles), according to traditional interpretations.
• Enveloping Layers: The universe is not just the inner space but is enveloped by seven material layers—water, fire, air, space, mind, intelligence, and ego. Each layer is ten times thicker than the previous one.
• Total Size: When accounting for these seven layers, the total diameter is calculated as over 5×10145 cross 10 to the 14th power5×1014 billion miles, which is often interpreted as approximately 90 billion light-years. 

Perspective on Cosmology 

• Inconceivable Size: He emphasized that these dimensions are inconceivable to the tiny brain of a human being and cannot be fully measured by human scientists.
• Innumerable Universes: He highlighted that this universe is considered the smallest among the innumerable universes, which exist in the material creation.
• Vs. Modern Science: He supported the view of the universe as a round sphere (bhu-mandala) by citing authorities like the Surya Siddhanta, Siddhanta Siromani, and Aryabhata.
• Purpose of Knowledge: He taught that the ultimate purpose of this knowledge is not mere physical measurement, but to recognize the supreme potency of God (Kṛṣṇa). 

In summary, Srila Bhaktisiddhanta Saraswati presented the Vedic view of a very large, layered, and multi-layered universe that is relatively small compared to the total material, and ultimately, spiritual creation. “

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