Valmiki Ramayana Yuddha Kanda Sarga 41 Shloka 19
Original Shlokaदृश्यन्तेनयथावच्छनक्षत्राण्यभिवर्तते । युगान्तमिवलोकस्यपश्यलक्ष्मण शंसति ।।6.41.19।।
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लक्ष्मण Lakshmana, नक्षत्राणि even stars, यथावत् so also, नदृश्यन्ते not visible, लोकस्य in the universe, युगान्तम् end of the universe, शंसतीव spots on the moon, अभिवर्तते dirty, पश्य seen.
"Just as the spots on the moon, the stars are also dirty and not visible. It forebodes the end of the universe Lakshmana!"