Canto 2 -
Ayodhyā-kāṇḍa
Chapter 78: Śatrughna Punishes Mantharā
Text 2.78.18

तेन भाण्डेन संस्तीर्णं श्रीमद्राजनिवेशनम्।
अशोभत तदा भूयः शारदं गगनं यथा॥

tena bhāṇḍena saṁstīrṇaṁ śrīmad-rāja-niveśanam
aśobhata tadā bhūyaḥ śāradaṁ gaganaṁ yathā

tena = with those; bhāṇḍena = ornaments; saṁstīrṇam = strewn; śrīmat-rāja-niveśanam = the beautiful residence of the king; aśobhata tadā = shone; bhūyaḥ = again; śāradam = the autumn; gaganam = sky; yathā = like.

Strewn with those ornaments, the beautiful residence of the king again shone like the autumn sky.

“Autumn sky” means “a clear sky with stars.”