Valmiki Ramayana Ayodhya Kanda Sarga 39 Shloka 18
Original Shlokaव्यराजयत वैदेही वेश्म तत्सुविभूषिता। उद्यतोंऽशुमतः काले खं प्रभेव विवस्वतः।।2.39.18।।
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सुविभूषिता well adorned, वैदेही Sita, तत् वेश्म that palace, काले at dawn, उद्यतः rising, विवस्वतः Sun's, प्रभा light, खमिव like sky, व्यराजयत got illumined.
Welladorned Sita illumined the palace like the rising Sun lighting up the sky at dawn.