Be as it may, grahaNa or eclipse has a different meaning for me. The sun being hidden by the moon to make it disappear from the earth's vision is of a deep philosophical significance. It has a hidden spiritual import; the prayers do too. Its a time for us to pray and ask the Sun to shine and bring us out of the darkness that moon has caused us to be in. The moon has not affected the sun, but only us earthlings. One is blinded by the darkness of ego and cannot see the Self. In other words, jIva is blinded by an ashuddha antahkaraNa that cannot shine the reflection of the Atman just as the moon doesn't shine anymore during the eclipse as we can see only the dark side of it.
As the chitta cleanses itself of all the dark habits, the Atman shines again as a reflection, at first in the antahkaraNa and then as the reflection itself burns the dust off the chitta, the Atman shines brightly, swallowing all the darkness there ever was. The sun alone remains when seen at directly, even with closed eyes. Wherever you look then, the sun will appear in bright spots on the vision elsewhere. That Atman once looked at directly (that is,by shravaNa, manana and nidhidhyAsana) too will appear in all our vision.
The prayers during the eclipse are really prayers for us to see that Sun which shines even during the nights, even in our deepest of sleeps; that Sun is the Self. The eclipse to get over is a wait for moksha. The moon covering up the sun is a natural occurrence, just as day-to-day things cause darkness in our lives. And this, my friends, doesn't happen to just you and me. Since its a karmabhoomi, - this Earth is - it occurs to anyone born here in any form. It happened to Bhagavan Rama as well!
As the legend goes, Rama was upset about his failing triumph over Ravana. Thats when Rama prayed to Agastya Rishi and took the upadesha on prayers to the sun, which came to be known as Aditya hRdayaM. Since time immemorial, stories in India are made in such a way that the meaning is applicable to daily life as it appears on the face of it, as well as containing a hidden teaching that will open up and become sAdhaka's tool during manana! Surely, this hymn helped Rama know the Truth and win over Ravana in the battle that followed thence.
The last two stanzas of Aditya hRdayaM go thus:
esha supteshu jAgarti bhUteshu parinishThitaHesha evAgnihotraM ca phalaM caivAgnihotriNAm (A.H. 23)
Salutations to the Lord who abides in the heart of all beings keeping awake even when they are asleep. He is both the sacrificial fire and the fruit enjoyed by the worshippers thereof.
vedASca kratavaScaiva kratUnAM phalameva cayAni kRtyAni lokeSu sarva esha raviH prabhuH (A.H. 24)
The sun is indeed the Lord of all action in this universe. He is verily the Vedas, the sacrifices ordained therein and the fruits thereof.