by The Great Christ Comet- Revealing the True Star of Bethlehem (retail) (epub)
By mid-July the comet would have been spectacular by any standard. With a magnitude like that of Venus and a large coma (perhaps over 2 degrees long), the comet, now almost as long as the Big Dipper, must have been very eye-catching. It was now becoming visible seven hours before sunrise. Since it was appearing each night within a few hours of sunset, it inevitably would have become a talking point within the general population all across the northern hemisphere. In outer space, the comet was about as far from Earth as Earth is from the Sun, and was fast approaching the orbit of Mars.
The comet’s procession to the Sun was truly majestic. No comet in recorded history ever put on a display like this. From the western fish of Pisces, the comet passed through the constellations Aquarius (July 26–August 8), Capricornus (August 8–13), and Sagittarius (August 14–21), past the right foot of Ophiuchus (August 21–24), and traversed Scorpius (August 25–September 2) and Libra (September 3–21) before ending up at the star λ Virginis (see fig. 10.8). This was the location of Virgo’s left foot, according to the Greeks, but of both of her feet in the conceptualization of Revelation 12:1. The Sun was a couple of degrees from Virgo’s brightest star, Spica, at the time.
FIG. 10.8 The course of the Christ Comet across the sky from December 17, 7 BC, to September 29, 6 BC. Image credit: Sirscha Nicholl, using modified versions of the constellation illustrations from Bloxam, Urania’s Mirror (images credit: oldbookart.com).
During its procession, the comet’s motion through the heavens was reminiscent of a bobsleigh from the point that it is approaching its greatest speed until it is almost stationary. All the while, the comet was growing in apparent magnitude. By the end of the journey it had the magnitude of the full Moon! During its procession the comet’s coma appeared large, larger than any coma in the last few hundred years. As for the tail, although it briefly decreased in apparent length at the end of July and the start of August, thereafter it grew very long very quickly. By mid-September the whole comet would have stretched halfway across the sky. We shall now take a closer look at a few key stages of the comet’s majestic procession.
Water from Aquarius’s Water Jar
We consider first the early stages of the comet’s journey across the heavens. Ever brightening and growing on its way, the comet revisited the water flowing from Aquarius’s water jug. Indeed, our orbit would suggest that, from July 25 to August 8, the appearance of the comet in the sky was radically reoriented, its direction swinging like a pendulum from left to right. It was reminiscent of a shuttlecock or birdie that is hit on the cork side and turns mid-air to fly cork-first. Initially the head was down to the left and the tail pointing up to the right, but by the end of the maneuver the head was down to the right and the tail up to the left.28 As it reoriented itself in this way, the tail was very short. It was shortest on August 4–5, when the comet was close to upright (relative to the constellation figure). As for the coma, it was probably very large at this point (its longest side perhaps something like 5–6 degrees in diameter).
What was happening in outer space was that Earth was crossing the “interchange,” or “crossroads,” between its orbit and that of the comet (see fig. 10.9). As a result, from the perspective of Earth the comet’s tail seemed to shorten, widen, and brighten dramatically as it shifted from one side to the other. The tail’s intensified brightness was due to the fact that more tail debris was concentrated into a small area of the sky in Earth-dwellers’ line of sight. Moreover, the geometry of the comet-Earth-Sun at this time would have boosted the brightness by something like 1 magnitude. Essentially, the comet was almost behind Earth from the perspective of the Sun (the phase angle of the nucleus peaked at under 3 degrees on August 4–5!) and the backscattering effect meant that the dust in the coma and tail became slightly brighter. The great size of the coma was because the comet was very close to Earth. Occurring in the context of Aquarius the Water-Bearer (in Babylonian thought, the Great One), the comet’s large, bright, and probably oval coma may possibly have appeared to be a water-jar and the short tail to be a stream of water issuing from it, on August 2 to 7. Over those nights, the angle of the coma and tail changed, making it look like the water jar was being swung by the constellation figure from his right to his left, rather like a pendulum.29 The constellation figure may well have seemed to observers to have come to life.
FIG. 10.9 The Christ Comet and Earth on July 30, 6 BC. The comet is just beyond the orbit of Mars as Earth crosses the comet’s orbital line. Image credit: Sirscha Nicholl.
On the nights of August 2/3 to 7/8, the comet was between 0.485 AU and 0.384 AU (approximately the same distance as Mercury is from the Sun) from Earth and heading straight toward the crossroads and the Sun, so that during this time humans would have been able to look directly at the sunward and active side of the large, oncoming comet. Had they been able to see what was happening in the coma, they would have caught a glimpse of magnificent fountains of dust jetting out from the nucleus (cf. figs. 10.10–11).30
FIG. 10.10 A drawing of the jets of Comet Daniel’s coma on August 5, 1907. Image credit: Max Wolf, Heidelberg Observatory/J. F. Julius Schmidt, in J. Rahe, B. Donn, and K. Wurm, Atlas of Cometary Forms (Washington, DC: NASA, 1969), 40.
FIG. 10.11 A drawing of Comet Tebbutt’s jets. Image credit: J. F. Julius Schmidt, in Atlas of Cometary Forms, 14.
The comet’s apparent magnitude would have been at least -7.131 at the height of the display on August 5, 6 BC. Of course, the fact that so much dust was now in Earth’s line of sight—and the backscattering effect—would have meant that the comet’s brightness was greater than the apparent magnitude value would suggest. On the other hand, the large size of the coma would have diluted the intensity of the brightness.
Jews might have been prompted to reflect on Isaiah 12:3—“With joy you will draw water from the wells of salvation” (cf. Isa. 32:1–2; 33:17–21; 35:1, 6; 44:2–3; 51:3)—and Numbers 24:7, where Balaam prophesied concerning Israel that “Water shall flow [or overflow] from his buckets, and his seed shall be in many waters.” In addition, the Feast of Tabernacles in the fall featured a rite in which water from the Pool of Siloam was poured out at the base of the altar of burnt offering in the Jerusalem temple.
In Babylonian tradition, the waters of the Great One could be associated with judgment and danger in the form of severe rainstorms and floods, but they were more commonly associated with the coming of the rains and hence with fertility, prosperity, refreshment, purification, and cleansing.32 Occurring in the summer, this celestial phenomenon would more naturally have been interpreted as having a positive meaning.
From early August onward, the comet appeared around sunset and remained visible until it set in the southwest. That meant that everyone could see the comet in all of its glory. It had become a third great light in the heavens.
The Archer’s Arrow
As the comet raced through Capricornus, its apparent magnitude would have become increasingly impressive, since the comet was not only getting closer to the Sun but was also coming closer to Earth. At the same time, this was counterbalanced by the fact that the brightness that the comet did have was being spread over a wider surface area.
By the time the comet entered Sagittarius the Archer, on August 14, 6 BC (according to our orbit), its apparent magnitude would have been at least -8.2,33 and it was only 0.334 AU from Earth (1.26 AU from the Sun), the closest it would come to Earth before making its dramatic U-turn around the Sun (fig. 10.12). That, incidentally, is closer than most of the historically great comets have ever come to our planet! The comet may have been about 40 degrees long, the coma itself something like 7 degrees in diameter (major axis). Earth now found itself at a perfect vantage point from which to watch the comet as it hurtled toward perihelion at breakneck speed.
FIG. 10.12 The Christ Comet and Earth on August 14, 6 BC. The comet is between the orbit of Mars and that of Earth. Image credit: Sirscha Nicholl.
Over the next month or so the comet would have bec
ome an increasingly bright light shining in the deep darkness. Even as the coma shrank in apparent size as the comet moved away from Earth, its apparent magnitude was steadily becoming greater as it neared the Sun—which meant more brightness concentrated in a smaller area. In addition, more and more of the comet’s tail would have been becoming visible to human observers each night. This was because the comet was continuing to race toward the interchange and was degassing more as it neared the Sun, while Earth, after crossing the underpass, was assuming a much better angle from which to see the whole comet. In fact, from the perspective of Earth, you would almost have thought that the tail was simply stretching as the comet raced across the constellations, because the end of the tail remained firmly fixed in Aquarius, back at the pivot point of the comet’s radical pendulum-swing reorientation. When the comet head departed from Aquarius, the whole comet would have been just over 14 degrees in length, but by the time the head reached the far side of Sagittarius, it would have been over 70 degrees long.
The comet must have seemed to observers to have transformed itself into a dramatic celestial arrow! The coma was the arrowhead and the tail was the shaft and fletching. It had become a flaming arrow fired from the Archer’s bow! (See fig. 10.13.)
To the Babylonians and Greeks, the Archer Pabilsag, or Sagittarius, was a winged half-horse and half-human creature known for his great bow and the arrow that is famously aimed right at the heart of the Scorpion (the star Antares). To the Babylonians, at least, Scorpius encapsulated the forces of wickedness, darkness, and death.34 Over the nights of August 17–20, it looked like the Archer was sliding the awesome arrow into his bow and then firing it.35 Even by the time the comet set on the 20th, the arrow could already be seen “in flight” toward Scorpius, such was the rapidity of the comet’s apparent movement across the starry heavens at that time. The cometary arrow’s movement would have been detectable in single observing sessions over the following 1½ weeks.
On August 25 the comet crossed Earth’s orbit. At that point Earth was about half the distance from the comet that both Earth and the comet were from the Sun. The comet, both its coma and its tail, would have been brilliant and large. Even as the giant arrow flew through the heavens, it would have grown in length. Sure enough, the cometary arrow, having grown to well over 80 degrees long, and having an apparent magnitude of at least -8.4,36 struck the Scorpion’s heart (it came very close to Antares on August 27–28). The cometary arrow continued on its celestial flight path until it hit the middle of the Scorpion’s forehead (δ Scorpii) on August 31.37 (See fig. 10.13.) By that time the comet would have extended more than halfway across the sky.
FIG. 10.13 The Archer (Sagittarius/Pabilsag) fires his great cometary arrow and it strikes the Scorpion’s heart and forehead in August 6 BC. Image credit: Sirscha Nicholl, using modified constellation images from Bloxam, Urania’s Mirror (images credit: oldbookart.com).
This was a truly astonishing drama, extending from one constellation to another. It was the stuff of myth! The Magi, along with everyone else who knew their constellations, must have been glued to the heavens each night as they watched the unfolding nightly drama.
While the cometary arrow flew through the sky from bow to forehead, the coma would have steadily shrunk in length from something like 7 degrees to about 4 degrees. Together with the building apparent magnitude as the comet approached the Sun, this shrinking of the coma would have intensified the brightness.
The celestial display had already been remarkable. Having watched what it did, the Magi may have concluded that the Star was signaling the demise of the forces of Chaos and Darkness in the cosmos. These forces were destined to be decisively and overwhelmingly conquered. Order would once again prevail in the cosmos. It is doubtful at this stage, however, whether the Magi associated the Star with the Jewish Messiah. Only later would they conclude that this was all one awesome celestial show to put the forthcoming nativity in cosmological and eschatological perspective. The Magi must have wondered what the Star would do next. Little did they know that all the things that had happened up to this point were just the prelude to the marvels about to occur.
The Wonder on September 15, 6 BC
On September 15, 6 BC, the comet was fast approaching perihelion—it was just 0.47 AU from the Sun and 0.93 AU from Earth (for comparison, Hale-Bopp never came closer to Earth than 1.32 AU). The increasing distance from Earth was because Earth’s course had taken it away from the comet even as the comet had crossed the interchange, heading toward the Sun (fig. 10.14).
FIG. 10.14 September 15, 6 BC—the comet is making its way past Mercury on its way to perihelion. Because Mercury is inclined to the ecliptic at an approximately 7-degree angle, the comet passes over Mercury’s orbital path before perihelion (even though the comet is below the ecliptic at that point) and under its orbital path after perihelion (even though the comet is then above the ecliptic). Image credit: Sirscha Nicholl.
On September 15 the Sun, making its way through Virgo, was located over her womb, while the Moon was under Virgo’s feet. The occasion is memorialized in Revelation 12:1.
The comet’s range of apparent magnitude values at that time is impressive (table 10.1).
Magnitude Slope
(value of n)
Apparent Magnitude on September 15, 6 BC, if first observed on November 21–28, 8 BC
Apparent Magnitude on September 15, 6 BC, if first observed on February 5, 7 BC
Apparent Magnitude on September 15, 6 BC, if first observed on May 29, 7 BC
Apparent Magnitude on September 15, 6 BC, if first observed on August 17, 7 BC
Apparent Magnitude on September 15, 6 BC, if first observed on September 30, 7 BC
Apparent Magnitude on September 15, 6 BC, if first observed on December 10–17, 7 BC
3
-10.7
-10.5
-9.5
-8.4
-8.1
-7.8
4
-13.9
-13.7
-12.5
-11.3
-10.9
-10.3
5
-17.0
-16.7
-15.3
-14.0
-13.5
-12.8
TABLE 10.1 The Christ Comet’s apparent magnitude on September 15, 6 BC.
If the comet was first discovered from May 29 to December 17 in 7 BC at an apparent magnitude of +3.4 and had an average slope value (i.e., n=4), then its magnitude on September 15 would have been between -10.3 and -12.5. If n=5, then the comet would have been between -12.8 and -15.3 on September 15. These numbers underscore the comet’s brilliance. Even at the minimum of these magnitude values, a comet would normally have been visible during the daytime.38 However, because the Bethlehem Star comet was large, the issue is not quite so simple. The coma could have been something like 2 degrees long. Accordingly, only a small part of the coma, namely the region of condensed brightness around the nucleus, would have been detectable during the daytime.
In normal circumstances that evening, observers in both Babylon and Judea, when they scanned the western sky under λ Virginis (= Virgo’s feet, in Rev. 12:1’s conception of the constellation figure; Virgo’s left foot, in the imagination of most Greeks) in the wake of sunset, would have seen only the slim crescent of the new Moon. However, this evening, right beside the Moon, they would have seen the comet’s coma, with its massive tail sweeping up to the left at a roughly 40-degree angle (relative to the ground). It is possible that the edge of the coma was slightly backlighting part of the edge (limb) of the Moon.
If these observations of the young crescent Moon were the first sightings of the new Moon in Babylon and/or Jerusalem, the comet’s presence may have been perceived to be enduing the occasion with special importance.
However, even if this was the first sighting of the new Moon in Babylon, the Babylonian method of determining the start of new months by advance calculation
would probably have resulted in the new month of Ululu starting on the evening of September 14, so that Ululu 1 was the evening-to-evening day September 14/15.39 Accordingly, what happened after sunset on September 15 would have taken place at the start of Ululu 2.
The Judeans, however, had an observational luni-solar calendar. As a result, if the new crescent Moon went unobserved on September 14, this sighting of the crescent Moon after sunset on September 15 would have coincided with the formal beginning of the new month, Tishri. In the Jewish calendar, Tishri was no ordinary month.40 It was the first month of the civil year. It was the month of months. And the first day of Tishri was no ordinary day—it was the Feast of Trumpets, Rosh Hashanah. It was a holy, solemn, and joyful holiday marked by the blowing of trumpets. Every Jewish month was announced by the blowing of trumpets, but Tishri 1 was set apart in that it was a day of trumpet blasts, presumably in that trumpets were to be blown all day long (Lev. 23:24; Num. 29:1–2a). The first sighting of the young crescent Moon in September was immediately followed by the blowing of the trumpets announcing the Feast of Trumpets and the beginning of the civil New Year. (See fig. 10.15.)