Obviously we do not know and can not know
for certain exactly what the Magi saw and when it appeared. If we assume though
that it was a nova in Aquila in 5BC – the
star described by the Chinese – we can make some guesses about what they might
have seen and where it would have appeared in the sky. We can calculate the
positions of the stars and planets with great confidence and enormous accuracy
for any place on Earth at any date and time going back thousands of years.
assume, as we suspect, that the Magi were Persians and observing from a point
close to Tehran. We go back in time to March 15th 5BC, close to the date of
appearance of the Star. Its position is marked with a yellow star. It is a
little way north of Alpha and Beta Capricornii and
below the tail of Aquila. The Star would have risen almost due East at around . At
this time of the morning, just before dawn, the Star would have been at
moderate altitude (30 degrees) to the south-east. The Sun itself would rise at
The sky seen from Tehran at 05:00am local time on March 15th 5BC
biblical text just says: “We have seen his star at its rising”. Around
local time the Magi would have seen a new star rise where there had been none
might assume that a watchman first saw the Star and that he would have alerted
his colleagues to the new phenomenon. Over the following nights people would
watch the new star. Typically a nova may take several days to reach its maximum
is a region of the sky with very few bright stars. Only Altair in Aquila is of first magnitude
(0.77). An interloper even of 2nd magnitude will stand out
tremendously. Apart from Altair, the next brightest star in this region is Nunki (sSagittarii) of magnitude 2.03 until we move round West to
the far brighter stars of Scorpius.
move forward two weeks to March 31st. By this time the Magi would
have analysed the Star, cast horoscopes and understood its importance. They
would have had time to prepare their journey and possibly set out already.
The sky seen from Tehran at local time on March 31st 5BC
today the Star is now in the south-east and 27 degrees high. Note that the
bright Last Quarter Moon is nearby. The Moon is 45% illuminated and immersed in
the stars of Capricorn, just below the star in the sky.
people assume that the Magi followed the Star to Bethlehem
but, if the Magi were to leave today, following the Star, they would end up in India so
we know that this part of biblical folklore cannot be right! We’ll see a much
more likely way for the Magi to follow the Star later.
the Magi came from Persia they would have had a long and arduous journey crossing mountains,
deserts, and major rivers. It is not a journey that they would have undertaken
lightly, nor one that would be accomplished rapidly. Even though a camel can
travel long distances rapidly when pressed, this journey of some 900 miles
(1450 kilometres) would almost certain have required several weeks.
April 22nd dawn has advanced a great deal – at it
is almost daylight. The Star is now high in the south shortly before dawn. At it
is 37 degrees high.
The sky seen from Tehran at 04:00am local time on April 22nd 5BC
time passes the Star – Nova Bethlehem – will pass its maximum brightness and
start to fade. As it does so a new factor will hamper visibility. Once a month the Moon passes relatively close to the position of
the Star. In early March the Moon was Last Quarter and not so bright as
to drown out the Star. By April 22nd though it
will be a Full Moon that is close to the fading Star. For several days,
perhaps as long as a week, the Star will be invisible as the Moon’s brilliant
light brightens the sky. The Magi will lose sight of the Star.
the planet Mars is alongside the Moon. Extremely bright at magnitude –2.1 will be in the head of the Scorpion, close to its much dimmer
Star is now due south at dawn. Let us suppose that the Magi arrived in Jerusalem
around this time. The Star that they had been watching would have disappeared.
However, as the days passed, the Moon would rise later and later and get
progressively smaller and further away. By April 29th the Moon is
now a waning crescent some 47 degrees away from the Star and on the 30th
it is now 60 degrees away from a 37% illuminated Moon that will now be little
impediment to seeing the Star as it fades away.
the Magi were to set out from Jerusalem to Bethlehem just before dawn – which has now advanced even further – on April 30th,
the Star would be 48 degrees high in the south. Bethlehem is
almost due south of Jerusalem and the Star would genuinely have seemed to go before them and hang
over the town of Bethlehem, as we see below.
The sky seen from
Jerusalem at local time on April 30th 5BC.
the Star genuinely did “go before them” on this short journey south to find the