Valmiki Ramayana Yuddha Kanda Sarga 100 Shloka 17
Original Shlokaतयोःशरपथंप्राप्यरावणोराजपुत्रयोः । स बभौ च यथाराहुःसमीपशशिसूर्ययोः ।।6.100.17।।
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सः he, रावणः Ravana, तयोः that way, राजपुत्रयोः two royal princes, शरपथम् arrows range, प्राप्य coming closer, शशिसूर्ययोः like Sun and moon, समीपे near, राहुःयथा like planet Rahu, बभौ looked
That way when the two princes came near the range of Ravana's arrows, it was like the Sun and the moon near planet Rahu.