Skandapurana 5.45.24

5.45.24

viśvāmitra muniśreṣṭha sadā me gagane sthitiḥ ..
muktvaikāṃ kārtikīṃ caiva kṛttikāyogasaṃyutām .. 24 ..

“O Viśvāmitra, best of sages, my stay is always in the sky, / except on the single full-moon day of Kārttika joined with the asterism Kṛttikā. 24”