Valmiki Ramayana Kishkindha Kanda Sarga 43 Shloka 57
Original Shlokaस तु देशो विसूर्योऽपि तस्य भासा प्रकाशते। सूर्यलक्ष्म्याऽभिविज्ञेयस्तपतेव विवस्वता।।4.43.57।।
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सः देशः that place, विसूर्योऽपि though without Sun, सूर्यलक्ष्मयभिऽविज्ञेयः appears as if Sun's radiance, तपता with blazing, विवस्वता इव by the Sun, इव as if, तस्य his, भासा by light, प्रकाशते shines.
'That place gets light and heat even though there is no Sun.