I've been asked why the title of this hymn is sūryamaṇḍalāṣṭakam, when it has twelve verses and a phalam verse. Written after the collophon is sūryamaṇḍaladvādaśastotram . I do not know where that came from, whether from the transcriber or from what he was transcribing. 

Is it possible that the aṣṭakam in the title doesn't refer to the number of verses but is a qualifier of sūryamaṇḍala in the title? I.e. sūryamaṇḍalāṣṭakam means "the eight circles of the sun" ?

The hymn is:

 sūryamaṇḍalastotraṁ athavā sūryamaṇḍalāṣṭakam

namaḥ savitre jagadekacakṣuṣe jagatprasūtī sthitināśahetave ।

trayīmayāya triguṇātmadhāriṇe virañci nārāyaṇa śaṅkarātman ।

namo\'stu sūryāya sahasraraśmaye sahasraśākhānvitasambhavātmane ।

sahasrayogodbhavabhāvabhāgine sahasrasaṅkhyāyugadhāriṇe namaḥ ॥

yanmaṇḍalaṁ dīptikaraṁ viśālaṁ ratnaprabhaṁ tīvramanādirūpam ।

dāridryaduḥkhakṣayakāraṇaṁ ca punātu māṁ tatsaviturvareṇyam ॥ 1॥

yanmaṇḍalaṁ devagaṇaiḥ supūjitaṁ vipraiḥ stutaṁ bhāvanamuktikovidam ।

taṁ devadevaṁ praṇamāmi sūryaṁ punātu māṁ tatsaviturvareṇyam ॥ 2॥

yanmaṇḍalaṁ jñānaghanaṁ tvagamyaṁ trailokyapūjyaṁ triguṇātmarūpam ।

samasta-tejomaya-divyarūpaṁ punātu māṁ tatsaviturvareṇyam ॥ 3॥

yanmaṇḍalaṁ gūḍhamatiprabodhaṁ dharmasya vṛddhiṁ kurute janānām ।

yatsarvapāpakṣayakāraṇaṁ ca punātu māṁ tatsaviturvareṇyam ॥ 4॥

yanmaṇḍalaṁ vyādhivināśadakṣaṁ yadṛgyajuḥsāmasu sampragītam ।

prakāśitaṁ yena ca bhūrbhuvaḥ svaḥ punātu māṁ tatsaviturvareṇyam ॥ 5॥

yanmaṇḍalaṁ vedavido vadanti gāyanti yaccāraṇa-siddhasaṅghāḥ ।

yadyogino yogajuṣāṁ ca saṅghāḥ punātu māṁ tatsaviturvareṇyam ॥ 6॥

yanmaṇḍalaṁ sarvajanaiśca pūjitaṁ jyotiśca kuryādiha martyaloke ।

yatkālakālādyamanādirūpaṁ punātu māṁ tatsaviturvareṇyam ॥ 7॥

yanmaṇḍalaṁ viṣṇucāturmukhākhyaṁ yadakṣaraṁ pāpaharaṁ janānām ।

yatkālakalpakṣayakāraṇaṁ ca punātu māṁ tatsaviturvareṇyam ॥ 8॥

yanmaṇḍalaṁ viśvasṛjaṁ prasiddhamutpatti-rakṣā-pralaya-pragalbham ।

yasmiñjagatsaṁharate\'khilaṁ ca punātu māṁ tatsaviturvareṇyam ॥ 9॥

yanmaṇḍalaṁ sarvagatasya viṣṇorātmā paraṁ dhāma viśuddhatattvam ।

sūkṣmāntarairyogapathānugamyaṁ punātu māṁ tatsaviturvareṇyam ॥ 10॥

yanmaṇḍalaṁ vedavido vadanti gāyanti yaccāraṇa-siddhasaṅghāḥ ।

yanmaṇḍalaṁ vedavidaḥ smaranti punātu māṁ tatsaviturvareṇyam ॥ 11॥

yanmaṇḍalaṁ vedavidopagītaṁ yadyogināṁ yogapathānugamyam ।

tatsarvavedyaṁ praṇamāmi sūryaṁ punātu māṁ tatsaviturvareṇyam ॥ 12॥

sūryamaṇḍalasustotraṁ yaḥ paṭhet satataṁ naraḥ ।

sarvapāpaviśuddhātmā sūryaloke mahīyate ॥ 13॥

iti śrī bhaviṣyottarapurāṇe śrīkṛṣṇārjunasaṁvāde

sūryamaṇḍalastotraṁ sampūrṇam॥

sūryamaṇḍaladvādaśastotram

Thanks,

Harry Spier