This is not the most comprehensive overview of the astronomical ceiling of Senenmut but it does cite the date I have seen before, calculated according to the "southern sky"--1534 BC.
http://arxiv.org/PS_cache/arxiv/pdf/0801/0801.1331v1.pdfMy guess is, given that it was Senenmut's own tomb, that this was supposed to reflect the heavens on the day of his birth. Horoscope, so to speak. If that's so, then the following must be taken into consideration. The tomb of Senenmut on the summit of the hill Sheikh abd-el Gurneh was not begun until "Year 7". This tomb and the other one, with the ceiling, in the environs of Deir el Bahri, are not mutually exclusive. The first was probably intended as a mortuary chapel and the one with the ceiling was Senenmut's intended place of burial. It was the "secret one", although Dorman, for one, believes it had royal sanction. According to portraits on ostraca, Senenmut was far from being a youngster by Year 7. This is the year in the reign of Thutmose III that is traditionally accepted as the year of the usurpation of royal titles by Hatshepsut--and also the start of her mortuary temple, Djeser-djeseru. If one surmises that Senenmut was born in 1534 BC, he may have been as old as 50 by Year 7. Anyway, the man is portrayed with a lot of wrinkles. That would put Year 7 at 1484. Well,it's as useful as anything else discussed here for chronological purposes. Alternatively, if 1534 is Year 7, then some of T III's own astronomical data must be checked.