Can you date the crucifixion of Jesus Christ using astronomy?

Many people have tried. In the December 22, 1993 issue of Nature magazine, Colin Humphreys and W. Waddington reviewed all of the previous attempts and came up with a date of Friday, April 3, 33 AD as a very likely candidate.

The basis for these predictions hangs upon several pieces of information in the New Testament. The crucifixion happened during the 10 years that Pontius Pilate was procurator of Judaea which was between AD 26 - 36 according to independent historical records, particularly the writings of the Roman historian Tacitus. There is no controversy over this piece of information since Pontius Pilate is a known historical figure mentioned by name.

All four of the gospels of Matthew, Mark, Luke and John agree that the crucifixion happened a few hours before the beginning of the Jewish sabbath which would be nightfall on a Friday, and within a day of Passover which is celebrated at the time of a Full Moon.

The Last Supper was a Passover meal which would have happened on the evening at the start of the festival calendar 15 Nisan. The Crucifixion occurred later that day. This, however, disagrees with John's date of 14 Nisan and those of the other gospels. So, here is where a bit of controversy begins to enter the story.

Humphreys and Waddington then assumed that both 14 and 15 Nisan are possible dates, and then consulted predictions of the lunar motion to determine for which dates between AD 26 - 36, either 14 or 15 Nisan fell on a Friday. These are the only dates possible for the Crucifixion as set by the Biblical evidence. The result is a set of 5 possible dates:

14 Nisan............ Friday 11 April AD 27   
                     Friday  7 April AD 30
                     Friday  3 April AD 33
15 Nisan............ Friday 11 April AD 27
                     Friday 23 April AD 34

What now begins is a process of elimination, which means that someone has to make a choice, and therefore introduce their own opinion.

AD 27 is too early because Luke carefully states that John the Baptist began his ministry the 15 year during the rein of Tiberius Caesar and had baptised Jesus. This would have happened in autumn of AD 28-29 or Spring 29-30. Also most scholars believe that Pilate had been procurator 'for some time' before the Crucifixion.

AD 34 is probably too late because it would have conflicted with Paul's conversion which is believed to have happened in 34 AD.

This means that 15 Nisan is excluded, leaving only 14 Nisan as a candidate, and that the interpretation of the Last Supper as a passover meal cannot be correct. Jesus died at the same time that Passover lambs were being slain which is consistent with the New Testament statements that "Christ our Passover is sacrificed for us".

There are now only two plausible dates: Friday, 7 April AD 30, and 3 April AD 33. John's gospel records that three Passovers occurred during his ministry which began AD 28. This would eliminate April 7, 30 AD, leaving only 3 April AD 33 as a surviving possiblility. These two dates are exactly those on which Biblical scholars seem clustered as the two favored dates.

To this debate, Humphreys and Waddington add a new factor which previous scholars had not included. In the Acts 2, 14:21 it was reported that the Moon would be turned to blood and the Sun turned to darkness at the time of the Resurrection. This observation also appears in the so-called 'Report of Pilate' which was written by Pilate to Emperor Tiberius. If this is taken as a lunar eclipse, then the Crucifixion can be dated exactly. Lunar eclipses were frequently described in exactly this way, even verbatum, by contemporary historians. Predictions show that there was only one lunar eclipse visible from Jerusalem at the time of passover in the period from 26 - 36 AD. It occurred on Friday April 3, AD 33. The Moon rose above the horizon already in the midst of eclipse and would have progressively 'turned to blood' as the eclipse continued.

So, a combination of astronomical detective work and using independent historical accounts confirms much of the details in the Gospels as being accurate, and moreover lets us state with considerable certainty when the Crucifixion occurred. A similar approach for the birth date of Christ is far more complicated because the Star of Bethlehem has been identified as a variety of different astronomical and astrological 'events'.

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