Astronomy web page  

Update April 14, 2016 The Lascaux Sky Chart

April 28, 2016
The conclusions on this page may include minor errors that have been corrected with the most recent Cartes du Ciel software update.  The web page The Lascaux Sky Chart includes these changes. These changes are NOT yet reflected in the web pages Astronomy.html, Lascaux.html, and ZodiacClock.html. In particular, the animations need to be corrected. This notice will be removed from the updated pages as the corrections are completed.

NOTICE: The Lascaux Sky Chart developed in April, 2016 shows that the Lascaux Cave Paintings include a sky chart from 17,800 BC, which indicates that they were painted at around that time. This may require some changes to this discussion of astronomy at Lascaux Cave.

In Celebration of Psalm Nineteen:
God's handiwork in Creation

David C. Bossard

"Let them be for signs and for seasons,
and for days and for years"
Genesis 1:14

It is nightfall, and Orion is about to pass below the horizon. The eye-catching stars of Orion's belt passed a few minutes earlier; only the red giant star Betelgeuse is still visible just above the horizon. To the west, the constellation Taurus is also sinking, with the horizon rising to touch the head of the great bull. The bull's eye -- the red giant star Aldebaran -- will fall below the horizon in another half-hour.

This scene was repeated every clear night, between late June and late December, for thousands of years either side of 15,000 BC. It is memorialized in a remarkable bull painting at Lascaux cave in France.

Well... all of this is dramatic, but how could this scene relate to a cave painting? And what does it say about the human race at that time?

NOTICE: The Sky Charts presented here are based on the program Cartes du Ciel (Version 3.6), a free open software program that uses the Hipparcos star catalog for star positions and movement.  This program implies a different precession of the Zodiac constellations through the years, as compared with other authors, particularly for years before 1,000 BC. See the page Zodiac Clock for further information.

Note: Click on the images in this page for an expanded view.

Animations on this page

Lascaux Cave Sky Charts

Bull Paintings overlaid on the Sky Chart for 15,300 BC:

Overlay of Bull #15 and Bull #18 (70° span of longitude; stars to mag. 4.8):
Left fit  (1400 x 1400 px, 39s; cf. Fig. 5) mp4 430 Kb  2.1 Mb  gif
Right Fit (1400 x 1400 px, 39s; cf Fig. 4)  mp4 418 Kb  2.0 Mb gif
Right Fit to m 5.8 (1150x900 px, 54 s)  mp4 487Kb  2.3 Mb gif

Extended Overlay of Bull #15 and Bull #18 (200° span of longitude; stars to mag. 4.8):
Left fit (4550 x 1375 px, 36 s; cf. Figs. 11-12)  mp4, 1.4 Mb  7.7 Mb gif
Right Fit (4550 x 1375 px, 36s; cf Figs. 13-14)  mp4, 1.3 Mb   7.4 Mb gif
Right Fit to m 5.8 (170° span, 3200 x 1250 px, 36 s)  mp4, 1.5 Mb  7.7 Mb gif

Zodiac Clocks (See web page)

Zodiac Clock Cycle (polar + perihelion precession) -- This animation shows the sky charts at the Autumnal Equinox (Sept. 21) at the transition between Zodiac Signs over a complete cycle (27,500 BC to 11,000 AD). (MP4, 1.4 Mb, 45 s).

Zodiac Clocks (polar + perihelion precession) -- This animation shows the zodiac clocks at 1000 year intervals over the above zodiac precession cycle cycle: 11,000 AD to 27,000 BC (MP4, 2.2 Mb, 2m 6s -- 900x900 pixels; 5 Mb gif animation here). 
Zodiac Clock (large): 4,000 AD to 15,300 BC (MP4, 1.9 Mb; 1m 8s - 2400x2400 pixels).

(Erroneous) Traditional Zodiac Clock (polar precession only) -- The above animations are consistent with the Cartes du Ciel sky chart. Many traditional calculations of the zodiac positions erroneously consider only polar precession, shown here between 4,000 AD and 15,300 BC (MP4, 1.3 Mb, 1m 15s; 2.1 Mb gif animation here). This animation shows the results of the erroneous calculation. See also Figure 4 of the Zodiac Clock Webpage.

Other Animations

Nightly Transits of Orion, Taurus and Pleiades:  2,000 AD  8.350 BC  10,000 BC and 15,300 BC.

24-hour Panoramic view of the Lascaux Sky:
Vernal Equinox, Mar. 20-21 (360° panorama) (MP4, 1m 42s, 1920x1080, 7.6 Mb)
Autumnal Equinox,  Sept. 20-21( 339 ° panorama) (MP4, 1m 42s, 1920x1080, 7.7Mb)

Movement of the Constellations 2,000 AD to 15,300 BC. This animation shows the constellations Orion, Taurus and Pleiades at the moment that Bellatrix, at the right shoulder of Orion, falls below the horizon. A zodiac clock shows the precession of the Equinoxes over this time interval.

Horizon Line Animation (cf Fig. 18). This animation shows changes in the slope of the line between Bull #18 and Bull #15 (cf. Fig. 2 and discussion).

Orion Zenith (cf. Fig. 19). This animation shows how the zenith of the Orion transit through the night sky changes through the years 5,000 to 17,500 BC. It shows that at least one star of Orion's belt does not show above the horizon at any time between 8,260 BC and 13,185 BC.

Ursa Major Transit, Spring Equinox (cf. Fig. 22). This animation shows that the Big Dipper falls below the horizon during the night and then rises at dawn at the Spring Equinox in 15,300 BC (MP4, 1.7 Mb, 37 s).

Ursa Major Transit, Autumnal Equinox This animation shows that the Big Dipper rises at sunfall and falls just before dawn at the Fall Equinox in 15,300 BC (MP4, 2.0 Mb, 45 s).

Full 24-hour transits of these constellations in 15,300 BC are: Vernal Equinox, Mar. 20-21 (360° panorama) (MP4, 1m 42s, 1920x1080, 7.6 Mb), and Autumnal Equinox,  Sept. 20-21( 339 ° panorama) (MP4, 1m 42s, 1920x1080, 7.7Mb).
Note: Click on the images in this page for an expanded view.

A Sky Chart at Lascaux Cave

Figure 1 is a portion of the Hall of Bulls in Lascaux Cave, France. The cave paintings in this part have been dated to 15,300 BC. Paintings of aurochs (extinct ancestors of the modern bovine) wrap around the hall. The bulls are painted on the limestone (calcite) vault and appear to stand on the darker stratum of sedimentary rock on which the vault rests.

Lascaux Bulls Panorama
Figure 1
Lascaux Cave Hall of Bulls

The section of our present interest (Figure 2) is Bull #15 and Bull #18 above and to the right of the person in the blue vest, at about 2 o'clock. Comparing the figures, it appears that Figure 2 is taken from ground level, looking upwards. This is the proper position to view the paintings, because five feet of  archaeological dig indicates that the present ground level was approximately eye level when the paintings were made. The insets of Figure 2 show the easily recognized constellations: Orion's Belt; the head of Taurus with the star Aldebaran for the Bull's eye, surrounded by the Hyades
01; and the Pleiades above.

Lascaux Bulls Panorama
Bull #18 Insets
Figure 2
Lascaux Cave Hall of Bulls
Bull #15 (left) Bull #18 (right)

I will show that this painting does much more than just incorporate a few familiar star groups. Bulls #15 and #18 taken together form a single star chart of astonishing accuracy. Because of possible photographic distortion, it is hard to know from this figure alone, how far the star chart extends to the left and right, but it certainly includes much of the central segment. Part of the evidence is that line that extends from the nose of Bull #18 to the back of Bull #15. Note that the line roughly parallels the "ground" level under the bulls.

I will also show that internal evidence from the painting itself implies that the painting was made between 13,200 BC and 17,000 BC, totally apart from radiometric or other evidence. This range nicely brackets the published date of 15,300 BC.

The Sky Chart at 15,300 BC.

A number of readily available star chart programs can show the sky as it would appear over a broad range of dates -- thousands of years in the past or future. The program I use here is Cartes du Ciel, also called Starry Night. This program takes into account the movements of the stars over time (generally very small), the precession (and wobble) of the Earth's North Pole, and precession of the Earth's orbit around the Sun. The Hipparcos Catalog is used for star information. This is based on the Hipparcos satellite measurements of proper star motion, accurate to a milli-arc second per year

Figure 3 is a star chart for 15,300 BC as it would be seen from Lascaux cave on September 21 just after midnight.02  The chart shows the horizon from the southeast (135°) clockwise through the south (180°) and west (270°), to north (0°). Yellow is above the horizon, grey is below the horizon, and tan marks the Milky Way. All of the stars shown should be visible to the naked eye (to magnitude 5.8). Lines indicate the constellations Orion and Taurus, and a circle marks the Pleiades.

At this moment, the star Bellatrix (gamma Orion), at the lower shoulder of Orion, just touches the horizon (see the inset for a typical representation of Orion showing the shoulder stars Betelgeuse to the left and Bellatrix to the right). This passage of Orion below the horizon can be viewed in the southwest on any clear night between late June and late December, in any year within a few thousand years of 15,300 BC

Sky Chart 15,300BC, 00h13m33s Orion
Figure 3
Sky Chart on September 21, 15,300 BC
as Bellatrix touches the horizon just after midnight (0h, 13m, 33s)
Source:  Cartes du Ciel
  Resolution: 1 pixel = 3 arc minutes
Inset: Orion

Figure 4 shows the Lascaux cave painting overlaid onto the central portion of Figure 3, after scaling and rotation
03a. This is part of an animation (mp4, 418 Kb). This overlay aligns the three rightmost spots of the painted belt with the sky chart. Figure 5 repeats this with the three leftmost spots (animation here: mp4, 418 Kb). Clearly either alignment yields a good fit, and it is difficult to know which was "original"03b. Both of these figures fit the brightest stars (the figures show all stars to magnitude 4.8)03c. The white circles that mark the stars are 1 arc degree in diameter, centered on the stars, so the painting reproduces the sky chart to within 30 arc minutes. The smaller circles are 30 arc minutes in diameter.

Lascaux Star Chart animation
Figure 4
Cave Painting Overlaid on the Sky Chart of Figure 3.
Source: Animation


Lascaux Star Chart animation
Figure 5
Cave Painting Overlaid on the Sky Chart of Figure 3.
Source: Animation

The horizon line. These figures suggest a reason for the line extending from the nose of Bull #18 to the back of Bull #15. It marks the horizon at the moment when Bellatrix passes out of view. The line joins Betelgeuse on the left, Bellatrix in the middle, and Pi-02 Orion at the Bull's nose (all within 30 arc minutes). Pi-02 Orion falls about 8 minutes after Bellatrix, followed in another 8 minutes by Betelgeuse -- if the horizon is a perfect horizontal line: I don't know what the actual horizon line (to the Southwest) would look like, viewed from Lascaux in 15,300 BC. I suspect that the painted line mimics the "ground line" below the bulls (below and a bit to the left -- see Figure 2), and is intended to signal "horizon line" (which to these stone age people certainly would not be thought of as a mathematically straight line as the sky chart shows it -- in truth it is no such thing!).

The elevation of Bull #18's horns also indicates a time towards the end of Taurus' transit of the night sky (Figure 6). When Taurus rises the horns are pointed sharply down towards the horizon; at the zenith the horns are more-or-less parallel to the horizon, and as it falls the horns are pointed up, as the painting shows. Figure 6 compares this with the present-day sky -- the day of the year is unimportant since the constellations at the end of their transit remain fixed relative to each other over the span of many years.

Figure 6
Appearance of Orion and Taurus
during a transit of the night sky04.

Figure 6 shows another difference between the sky of 15,300 BC and the present day. In the present era, Aldeberan, the Bull's eye, leads Orion both in rising and in falling. In 15,000 BC Aldeberan led Orion in rising, but Orion led Aldeberan in falling. The cave painting also shows Orion leading Aldebaran in falling, consistent with a night sky from around 15,000 BC and definitely not consistent with a modern sky. Incidentally, the month or day in a year does not matter: the rise will always look like the left side of Figure 5, and the fall will always look like the right side.

The Taurus Constellation. The usual depiction of the Taurus constellation extends the horns to Zeta Taurus and al Nath (el Nath) -- see Figure 7, left. In the Lascaux painting it appears that the horn of Taurus on the left extends to Propus (1 Gemini)
05. The other horn may be extended for artistic symmetry.

Taurus Constellation Taurus Horns
Traditionally the horns extend
to zeta Taurus and Al Nath
The left horn at Lascaux extends
to Propus (1 Gemini)
Figure 7
The Horns of Taurus

There is a story behind this conclusion. My first attempts to relate the Lascaux paintings to a star chart began with Taurus. By appropriate scaling and rotation it was possible to match the Bull's eye, Zeta Taurus and al Nath to the star chart, and as I did this I noticed that the back of Bull #15 followed a line of bright stars (Figure 4 or 5), which was the first indication that perhaps these two paintings formed a single star chart. Shortly after this I also noted that appropriate sizing could also include Orion's belt. However the stars in the horns of Taurus always fell short of the tips. After a prolonged period I noticed that most of the attempts ended up with the left horn tip near to 1 Gemini. From this I conclude that the original painting intended to use this star to mark the tip. The resultant fit is as shown in Figures 4 and 506.

The Pleiades. Unlike the spots that mark Orion's belt, the six spots over Bull #18's shoulder that recognizably represent the Pleiades constellation, are not and could not be part of a larger sky chart
06a. The reason is that a line extended from the upper stars of the constellation should pass through (or close to) Aldebaran (Figure 8a). There is no time within the span of human existence, as far as I am aware, in which a sky chart would place Taurus as high in the sky as this line extending from the painted spots would imply.

On the other hand, the depiction of Pleiades does accurately represent the actual constellation (Figure 8b) -- the spots are roughly 15 arc minutes in diameter. Thus I believe that the spots are an inset to the sky chart showing an enlargement of the actual Pleiades constellation, but deliberately skewed to tag it as an inset, rather than as part of the sky chart (along with the horizon line, another "signal" to show intent in the absence of a written language)

Figure 8a
Location of Aldeberan relative to the Pleiades
Figure 8b
The Pleiades
(Rotated) constellation compared with painting

Orion's Belt. Figure 9 is a close-up of Orion's Belt, from Figures 4 and 5.

First, note the painted horizon line, which appears to join Pi-02 Orion on Bull #18's nose with Bellatrix on the horizon and Betelgeuse on the back of Bull #15. The sky chart time (from Figure 3: September 21, 15,300 BC at 13 m 33 s after midnight) was, as noted, chosen so that Bellatrix is precisely on the (mathematical) horizon as seen from Lascaux cave.

All of the bright stars in the Cartes du Ciel chart are well within 30 arc-minutes of the painted horizon line, the painted back of Bull #15, and the selected spots of Orion's Belt, as well as other features of the larger sky chart. These two fits of the painting to the sky chart involve slightly different values for the two adjustments of scaling and rotation -- as can be seen in the fits to Bull #18's nose: Figure 9b includes a star as part of the Bull's nose that is apparently orphan in Figure 9a. In additon the stars along the back are more accurately located, but both figures are well within 30 arc-minute accuracy (and in addition it is possible that slight further adjustments might improve either of these fits -- see footnote 6).

Figure 9a (from Figure 5)
Sky Chart overlaid on left spots of Orion's Belt
Figure 9b (from Figure 4)
Sky Chart overlaid on right spots of Orion's Belt

The "sword".  Between the bulls is a "sword" (Figure 10). In this figure all stars up magnitude 5.8 are circled to give the outline better definition. Of course I doubt that it is a sword because metals were unknown in 15,000 BC, and indeed the markings may not be connected in the mind of the painter. In this figure, all of the visible stars to magnitude 5.8 are circled.

Figure 10
Note: Circles are stars to m5.8

How extensive is the Sky Chart? Thus far it seems clear that the painting in the immediate vicinity of Bull #18 is a sky chart. But how far does the chart extend to the left and right of this central region. Is the entirety of Bull #15 a sky chart? Is the body of Bull #18 also part of the sky chart? What about paintings further to the left of Bull #15?

Because of photographic distortion (compare the distortion between Figures 1 and 2) more careful photography would be needed to answer this question definitively. Nevertheless it is an interesting exercise to see what happens by matching all of Figure 3 to Figure 2. The results are shown in Figures 11 to 14
07. All of the stars up to magnitude 5.8 are shown, and stars that appear to match the outlines of the bulls are also marked by lines, which should be viewed as somewhat speculative -- not only because of possible photographic distortion, but also because it is notoriously easy for the mind to see patterns (lines) in the stars that were not seen by the cave painters.

Lascaux Bulls Panorama
Figure 11
Figure 2 overlaid on the Sky Chart of Figure 1
Matching leftmost dots of Orion's Belt
All stars to m5.8 are shown

Lascaux Bulls Panorama
Figure 12
Figure 2 overlaid on the Sky Chart of Figure 1
Matching leftmost dots of Orion's Belt
Animation (1.4Mb)

Lascaux Bulls Panorama
Figure 13
Figure 2 overlaid on the Sky Chart of Figure 1
Matching rightmost dots of Orion's Belt
All stars to m5.8 are shown

Lascaux Bulls Panorama
Figure 14
Figure 2 overlaid on the Sky Chart of Figure 1
Matching rightmost dots of Orion's Belt
Animation (1.5Mb)

Subject to all of these caveats, here are some specific comments referring to Figure 14.

Outlines of Bull #15. A series of bright stars (up to m4.8) follows the back of Bull #15. Adding stars to m5.8 fills this in somewhat, and the result is a fairly complete outline of Bull #15 extending from below Bull #18 eastward to include the head and horns of Bull #15.

At the extreme eastern edge of Figure 2, the back of Bull #13 (see Figure 15) also may follow lines of stars.

Outlines of Bull #18. Adding stars to m5.8 gives better definition to the outline of Bull #18's head, horns and back. It is also possible that the tail is marked by stars.

What about Bull #13? One might extend the painting to include Bull #13 (see Figure 15). We will not consider that here, but it might make an interesting investigation (see the Box).

Bull #13
Figure 15
Bull #13 (East of Bull #15)

 Hypothesis to test: That the bulls are constellations "standing" on the horizon represented by the line between the white limestone and the dark sedimentary layer below.

Procedure (applied to Figure 15): Advance the sky chart so that the region of sky that is filled by Bull#13 is at the horizon line defined to the south as viewed from Lascaux Cave. Scale and rotate the painting so that the horn of Bull #15 (at the top right) matches the stars indicated in Figures 11-14. Then look for matches with star magnitudes 4.8 or brighter and the features of Figure 15 -- particularly the back, head and legs.

Date of the Painted Sky Chart.

NOTICE: The Lascaux Sky Chart developed in April, 2016 shows that the Lascaux Cave Paintings include a sky chart from 17,800 BC, which indicates that they were painted at around that time. This may require some changes to this discussion of astronomy at Lascaux Cave.

Internal evidence shows that the Lascaux sky chart must have been painted between 13,200 BC and 17,000 BC -- and possibly a more careful analysis might narrow this range further. The reasoning is presented here.

Movement of the Constellations. To begin, Figures 16 and 17 show how Orion, Pleiades and Taurus change their relative positions over the years between 2,000 AD and 15,300 BC. This figure is part of an animation (2.1 Mb) that shows the progression over this time span
. The Zodiac clock shows the signs of the Zodiac with the Winter Solstice (Nominally December 21) at 12 O'clock Most of the sky charts displayed above are for September 21, the Autumnal Equinox shown here at 9 o'clock, when Orion falls just after midnight08.

Orion Motion
Figure 16
Constellations at 2,000 AD and 15,300 BC
Note: Time is adjusted so that Bellatrix (Orion's shoulder on the right) is fixed at the horizon line.
source: Animation (2.1 Mb)

Orion Motion
Figure 17
Constellation Movement 2,000 AD to 15,300 BC
Note: Time is adjusted so that Bellatrix (Orion's shoulder on the right) is fixed at the horizon line.
source: Animation (2.1 Mb)

Movement of the Horizon line. If one accepts the conclusion that the line extending from the nose of Bull #18 represents the horizon line, then rough bounds on the likely dates of the paintings can be had by examining the skew of this line over the years (Figure 18). If the artist placed the horizon line accurately, then it is evident that the painting must have been made no earlier than about 17,000 BC or later than about 10,000 BC, because outside of these limits the painted line is visibly skewed (see animation here) 08a.

Horizon lines with time
Figure 18
Slope of the Painted Line
when Bellatrix is located at the Horizon
10,000 to 18,000 BC
Note: the indicated line passes just below Betelgeuse and Pi-02 Orion as does the painted line in Figure 9.

Visibility of Orion's Belt. Orion's belt is a prominent part of the Lascaux painting of Bull #15, and it is unimaginable that the painting would have been made at a time when the belt doesn't appear in the night sky. Figure 19 is part of an animation (385 Kb) that shows the zenith of Orion between 5,000 BC and 17,500 BC, as viewed from Lascaux. The animation shows that the belt is not visible at any time between 8,550 BC and 12,550 BC and that at least one of the stars of the belt is not visible between 8,260 BC and 13,185 BC.

Combining the need for Orion's belt to be visible for the paintings, this puts a latest date at about 13,200 BC because consideration of the horizon line (Figure 18) rules out the possibility that the painting was made after 8,550 BC, when the belt is again visible.

Combining the visibility of the Belt with the need for the painted horizon line to be roughly horizontal means that the painting was made between  13,200 BC and 17,000 BC independent of any other dating methods. It is gratifying that this range nicely brackets the date of 15,300 BC determined by standard radiometric and other considerations

Orion Zenith (animation)
Figure 19
Orion at its Zenith, 10,000 BC
(Below the horizon)


What event does the painting point to?  The significance of these paintings is tied to an understanding of how the Orion, Taurus and Pleiades constellations relate to the Spring/Fall Equinoxes and the Summer/Winter Solstices. Consequently one's conclusions depend critically on how one calculates the precession of the equinoxes as reflected in the zodiac clock. If that precession is determined using only precession of the earth's axis then in 15,300 Taurus will be the sign for the Autumnal Equinox. However if both polar precession and the perihelion precession of the Earth's orbit is considered then in 15,300 Taurus will be the sign for the Winter Solstice. The Cartes du Ciel sky chart program, and hence this web page, considers both precessions, and so it favors the winter solstice interpretation. For further details see the Zodiac Clock web page

The fall of Orion (Betelgeuse and Bellatrix) below the horizon occurs nightly between late June and late December. Figures 4 and 5 apply to any date in this interval. I suggest that the painting was used to identify the Summer and Winter Solstices, marking the beginning of Summer and Winter. For purposes of this discussion, the times of sunrise and sunfall through the year are assumed to be comparable to the current times (2,000 AD) as shown in Figure 20.

Around the Winter solstice the sun rises at Lascasux (45°N lat) at about 7:30 AM and sets at about 4:15 PM. Near to the Summer solstice the sun rises at about 4:08 AM and sets at about 7:45 PM. These sunrise and sunfall times are applicable to 2,000 AD. I assume similar times would apply for any year.

Zodiac Clock showing Sunrise/Sunset
Figure 20
Zodiac Clock at 15,300 BC
Showing Sunrise and Sunset Times
(based on 2,000 AD times)

Winter Solstice. Here is how Orion figures into the determination of the winter solstice (nominally December 21). I would assume that these stone age people would have no precise ability to measure time, so the precise date of the shortest day of the year -- or its significance as the shortest day -- would (probably) be of little interest. However the time is an important marker in the year: it marks winter's beginning, important in the fight for survival.

In the weeks approaching the winter solstice Orion gradually disappears from the night sky, beginning with Saiph around December 1 and ending with Betelgeuse around January 12. Figure 21 shows the fall of Orion 30 minutes after sunset, at which time the night sky may be dark enough to see the constellation. After each date, the stars are no longer visible in the night sky until the constellation rises at dawn in the reverse order beginning around mid February.

Orion at Winter Solstice
Figure 21
Fall of Orion at Sunset
Winter Solstice
Note: Time is 30 minutes after sunset. All of these stars are bright and clearly visible in the deepening dusk after sunset.

Summer Solstice. Figure 22 shows the analogous times for the Summer solstice. In this case, the fall of Orion begins in the night sky with the fall of Saiph on June 19. After July 29 the fall of the entire Orion constellation can be observed in the night sky. As time passes the fall of Orion occurs earlier in the night sky until it begins to fall at sunset near to the Winter solstice, as shown in the previous Figure 21.

Orion at Winter Solstice
Figure 22
Fall of Orion at Sunrise
Summer Solstice
Note: Time is 30 minutes before sunrise.

These observations lead to the following general rules to identify the start of the Summer and Winter seasons around 15,300 BC:

Summer Solstice. Summer begins when Orion (Saiph) begins to fall at dawn. Prior to this, Orion is visible in the sky but dawn occurs before the constellation falls below the horizon.
Winter Solstice. Winter begins when Orion falls at sundown. In the days prior to this, Bellatrix can be observed to fall earlier in the evening, night by night. The solstice occurs (not that the precise time is of direct interest to the stone age astronomers) as Orion's belt (Zeta Orion) begins to fall.

Vernal Equinox.
The constellation Ursa Major provides a remarkably accurate marker for the Vernal Equinox around 15,300 BC. Four stars in the constellation rise together just before dawn on March 21 (Figure 22). Dubhe is the first to appear around March 5, giving 2 weeks' advance notice. After this first appearance the Big Dipper can be seen in the pre-dawn sky until it gradually falls below the horizon during November and December. In the modern sky, the Big and Little dippers never fall below about 10° above the horizon, so they are visible at any time on any clear night all year long.

Ursa Major at Spring Equinox
Figure 22
Spring Equinox March 21, 15,300 BC
Ursa Major Rising 30 minutes before Sunrise

 Hypothesis to test: That the Hall of Bulls contains a sky chart of Ursa Major "standing" on the horizon.

Observation: Next to Orion/Taurus, the Big Dipper is one of the most prominent features in the night sky. From Figure 22 it is evident that this constellation also signals an important event around 15,300 BC: the Spring Equinox, when earth's vegetation begins to emerge.

Conjecture. If Ursa Major is depicted in the Hall of Bulls, the rising configuration of Figure 22 is probably the way it is shown. The figure is probably facing right (facing Bull #18) and would likely be located to the left near the entrance.

Autumnal Equinox. The constellation Ursa Major also provides a marker for the Fall equinox around 15,300 BC, but it is not as precise as in Spring. The configuration shown in Figure 22 occurs 30 minutes after Sunset around September 1 rather than at the precise Autumnal Equinox of September 21. Figure 23 shows the rise of Ursa Major on September 21 -- but it is at 5:16 PM, before sundown, which occurs just before 6 PM.

Ursa Major at Spring Equinox
Figure 23
Fall Equinox September 21, 15,300 BC
Ursa Major Rises at 5:16 PM

A Panoramic View of the Lascaux Sky.
A panoramic view of the Lascaux sky shows the relationship between these constellations -- Ursa Major, Ursa Minor, Orion, Taurus and the Pleiades. Figure 24 shows a panorama for March 21. Full 24-hour transits of these constellations in 15,300 BC are: Vernal Equinox, Mar. 20-21 (360° panorama) (MP4, 1m 42s, 1920x1080, 7.6 Mb), and Autumnal Equinox,  Sept. 20-21( 339 ° panorama) (MP4, 1m 42s, 1920x1080, 7.7Mb). This shows how the Ursa and Taurus groups are related: The Ursa group rotates around the North pole and the Taurus group rotates around the South pole. At the moment shown in Figure 24, both constellations are rising at the horizon.

Ursa Major at Spring Equinox
Figure 24
Panoramic View
Spring Equinox March 21, 15,300 BC
Ursa Major Rising 30 minutes before Sunrise

Comments on the preservation of the paintings.
At some point after 6,400 BC
the entrance to Lascaux cave collapsed and the cave could not be accessed. It apparently remained closed off until it was discovered by some exploring boys in 1940.

Since this discovery, the paintings have been ravaged by exposure to the atmosphere, changes in moisture, and airborne pathogens. This is true for all of the cave art discovered since Altamira cave first came to light in 1880. Apparently until they were discovered, all of these caves existed in a protective bubble, sealed off from the outside world. Once they came to light, that bubble burst.

Without extraordinary efforts at preservation, time will degrade the paintings beyond recognition, and they will live on only as a memory. Perhaps I am too pessimistic, but I think it likely that restoration work will gradually replace the original painting so that at some point in the mid-term future, all that will remain is a representation of the original painting rather than the painting itself11.

Here is the shocker, that should give any scientist pause. There is nothing about the modern times that made the discovery of these paintings easier in 1940 than it would have been at any other time in the past. But imagine if the cave paintings had been discovered at any earlier time over the 10,000 years since the cave was sealed. Suppose it had been discovered 500 or 1,000 years ago.

If that had happened, it seems likely that the very existence of these paintings would have faded into the mists of folklore and legend, and readily been discounted by scientists, even more easily than they discounted the discoveries at Altamira until further cave art found in other caves forced them to retract their dismissive views. In my view it is an act of God's providence that the art caves of France were hidden from human eyes for the many millennia until their discovery in the late 19th Century when scientific methods could be used to preserve and photograph the paintings.

Apart from this providential act of preservation, the witness to the skill of these ancient humans would have been lost, along with the demonstrable fact that these ancient humans had the technology to produce not only astonishing feats of artistic work, but also were able to produce accurate star charts -- transferring what they saw in the sky onto the surface of a cave, and with remarkable accuracy. And all of this was done as far as we can determine, without instruments of any kind, certainly without metal instruments.  How did they achieve such precision at that time deep in pre-history? 

How was this star chart made? If you concede that this is an ancient star chart of amazing accuracy, it is natural to ask how it could have been made by ancient star-gazers who had no modern or even ancient (by our reckoning) technology to produce the tools -- no metal fabrication, for example? I am now speculating, but I think some worthwhile remarks might be made in the spirit of who-done-it reasoning.

Any star chart must begin with the selection of a triangle of stars that serve as reference points to orient and scale the chart. All other stars are then plotted relative to these. That is how Tycho Brahe, for example, corrected the Ptolemaic star catalog back in the late 1500s.

When one examines the Lascaux sky chart several possibilities occur. My suggestion is that the anchor stars were one in Orion's Belt (either on the left or right, depending on whether the fit is Figure 4 or Figure 5), Aldeberan, and and the tip of Taurus's left horn, Propus (1 Gemini). Another possibility is that the focus was the stars Betelgeuse and Belleron combined with 1 Gemini -- although I think that the prominence of Orion's belt almost certainly implies that one of the anchor stars was located there. NOTE: See LascauxSkyChart.html for an update to this conclusion.

What does the painting say about human activity in 15,000 BC?  First, given the agreement with the star chart, can anyone plausibly deny that this painting is intended to be a star chart, and that Bull #18 represents the constellation Taurus?

These paintings must have been made by people who had great skill and could transfer a map of the sky onto the 3-domensional cave walls and wrapping up into the vault, with a level of precision (as viewed at a distance) and an appreciation of perspective that is truly remarkable -- it would be remarkable today if done by hand without special instruments. It appears -- because of the close fit between the sky chart and the photograph -- that the painting was made to be seen from a single viewing position, as if one were actually looking at the sky stretching across the horizon. That is no easy feat, working on a 3-dimensional surface!

Because the artist accurately positioned Orion's belt below the horizon, it is clear that there was a general understanding that the stars are in fixed positions relative to one another, and that passing below the horizon does not change that. Since the sky is moving at all times, this painting had to be planned, and had to be based on constantly changing geometric relationships between the earth and the fixed stars. One can only speculate on what sort of coordinate chart and method of measurement and record-keeping they used.

The following summary of paleolithic cave art from U. Mass (Boston) reflects my own views with some caveats (emphases added):

"Around 40,000 years ago, modern humans (homo sapiens sapiens) migrated from Africa to Europe. Biologically identical with contemporary humans, the migrants had the same physical and mental capacities that we possess, though they lacked the thousands of years of cultural development that are now behind us. They arrived in Europe around the height of the last glacial advance, and learned to survive in the extreme cold by sewing animal skins together into warm clothing, and hunting the migratory herds of reindeer, bison, and other big game animals that roamed Ice Age Europe. The earliest examples of European cave art that have been discovered date back approximately 32,000 years. They already include fine examples of realistic painting, and so must have been preceded by a long-term development of artistic style and technique. Their beauty still moves us more than 30 millennia after they were created. The most recent cave paintings, including some at Lascaux, date back to around 9,000 BCE. At first, the painters created their works at the cave entrances or in very shallow areas. As the millennia progressed, they ventured further, ending in the deepest parts of the caves. In order to get to such depths, they sometimes had to overcome dangerous cave-dwelling  felines and bears, break through walls of stalagmites, and even cross underground lakes. Such excursions were made possible by the invention of fat-burning lamps capable of illuminating the total darkness. The incredible effort it took to penetrate into the depths of the earth suggests that the caves were not the equivalent of contemporary art galleries, and that the paintings had a sacred or ritual significance." [Emphases added]

I would add scientific or educational significance to the last sentence of this quote. In my view it is clear that -- whatever its other significance -- this painting served as an educational tool to train budding astronomers to discern the "signs and seasons".

Finally, it appears that the concern for accuracy in the sky chart went beyond the need to identify the seasons. My own conclusion is that the artists worked with scientific accuracy as an end in itself, truly a mark of the scientific spirit of inquiry. Could anything more assuredly mark the workings of the true human spirit? One could make an extensive list of the highly developed skills needed to carry out this sky chart project -- a task that we will leave undone because it is beyond our present purposes.



The background is an astrolabe used by Tycho Brahe to measure star positions in the sixteenth century AD. This illustration is from Tycho Brahe,
Astronomiae Instauratae Mechanica:

Brahe Instrument

^n01 Aldeberan = "The Follower" (follows the Pleiades) is the Arabic name; the Latin name is Palilicium = "Bull's Eye". I should note that there is no direct indication that the constellation Orion as a whole was recognized as a separate entity by the Lascaux cave painters. I use the modern representation of this constellation as a matter of convenience. Clearly the belt had special significance.

^n02 Lascaux cave is located at latitude 45° 2' 57" N and longitude  1° 10' 34" E. One of the curious features of the Cartes du Ciel program is that it shows the outlines of the constellations using current positions. Thus the charts for ancient times show the wandering of Aldebaran away from its present position. Al Nath wanders almost as much and in the same direction, so the horns are more spread apart in 15,000 BC than they would be today.

^n03 In the present-day sky, the fall of Orion is visible at night between January and June, almost 6 months out of phase relative to 15,000 BC.

^n03a  The scaling involves two parameters: (1) width/height scale, and (2) rotation angle.

^n03b  My speculative view is the fit to the left spots is "original" and at some point a fourth spot was added and the fit shifted a bit because the right fit seems to be a little better (particularly the back of Bull #15 and the nose of Bull #18). The spots are quite permanently embedded into the calcite. The calcite surface of the cave is somewhat cauliflower-like, and the paints are applied by daubing with bristles, or by blowing paint through a tube onto this porous surface. The result is that the colors embed into the calcite. Removal of a spot would be impracticable.

^n03c The animation here (487 Kb) shows Figure 4 with the contribution of stars of different brightness (magnitudes 4.3, 4.8, 5.3 and 5.8 -- all visible to the naked eye). An extended version of this animation (corresponding to Figure 12) is here (1.5 Mb).

^n04 The Earth's  polar precession has a period of  25,694.8 years (Source: Astrology Weekly; Wikipedia quotes 25,772 Julian years). The Earth's orbit around the Sun precesses with a period of 112,000  years (Wikipedia).

Here are actual star charts for the transit in 15,000 BC and 2,000 AD.

Animations of these transits are: 2,000 AD  8.350 BC  10,000 BC and 15,300 BC.

Typical Night Transit of Taurus and Orion across the sky in 15,000 BC
Cartes du Ciel
(double click for larger viw)

Typical Night Transit of Taurus and Orion in 2,000 AD

Note: The mid-transit chart is at a different scale because the constellations rise much higher in the sky
as compared with the transit in 15,000 BC.
Cartes du Ciel
(double click for larger viw)

The Cartes du Ciel star database (Extended Hipparcos compilation) gives Propus as the common name for both 1 Gemini and Eta Gemini. I leave it to someone else to resolve this issue.

The two parameters for scaling and rotation (in that order) were obtained by trial and error, not by a formal mathematical determination. It is entirely possible that better matches between the Lascaux paintings and the star charts are possible using a formal least squares methodology. I have not pursued this (even though I am a mathematician and have done similar things in the past).

In addition, a thin line in the painting just to the right of the fourth spot in Orion's belt may point to Bellatrix (it seems parallel to the line between the right side of the belt and that star). I have not attempted to fit the painting to the sky chart using this line.

^n06a  It appears that there is disagreement on this, but I do not see how any other conclusion could be made. See Michael Rappenglück (U. Munich), The Pleiades in the Grotto of Lascaux (1997).

^n06b  Notice that the left-most spot in Figure 8b is elongated. This is curious because in fact the seventh star in the Pleiades constellation (known worldwide as the "seven sisters") is adjacent to this star (see the following figure).

The Seventh Sister
(magnitude 5.05)
Compare Figure 8b.

^n07 These figures are obtained by combining various combinations of layers:
(1) Sky Chart BC15300Sep21001333Ext.gif - 209Kb
(2) Stars to m4.3 - 25Kb
(3) Stars m4.3+ to m4.8 - 16Kb
(4) Stars m4.8+ to m5.3 - 20Kb
(5) Stars m5.3+ to m5.8 - 29Kb
(6) Bulls123: fit to left three spots in Orion's Belt - 3.6Mb
(7) Lines 123: Fit of lines on Bulls123 (stars to m4.8) - 29Kb
(8) 1° circles about stars to m4.8 to overlay on Bulls123 - 41Kb
(9) Bulls234: fit to right three spots in Orion's Belt - 3.2Mb
(10) Lines 234: Fit of lines on Bulls234 (stars to m4.8) - 29Kb
(11) 1° circles about stars to m4.8 to overlay on Bulls234 - 41Kb.

^n08  See this web page for a discussion of the zodiac clock. Note that many, perhaps most, web-accessible treatments of the precession of the Equinoxes consider only polar precession. A correct treatment must also consider perihelion precession. The erroneous treatments place Taurus at the autumnal equinox around 15,300 BC, whereas in fact it should mark the winter solstice at this time.

^n08a Over the 10,000 years either side of 15,300 BC these stars will have proper motion of under 5 arc-minutes, and so their positions are stable within the sky chart and painting overlay.

Perhaps some further comment on proper motion is warranted. Proper motion (the motion of a star relative to the fixed galactic coordinate system) is measured in milli-arc seconds per year (mas). In 17,300 years (going back to 15,300 BC), 10 mas ~ 3 arc minutes or 1 pixel at the resolution of the sky charts shown here.  Typical stars named here have proper motion under 30 mas -- 3 pixels or 10 arcminutes -- well under the 30 arcminute apparent accuracy of the paintings. Consequently, projecting the sky chart 10,000 years on either side of 15,300 BC hardly changes the relative positions of these stars. Aldeberan is an exception to this rule: its proper motion is about 200 mas or 1 arc degree over the 17,300 years, ±35 arc minutes over ±10,000 years.


^n10   Carbon dating of carbon traces in the cave have been reported in a 1997 article as follows:

"Eight carbon fourteen datings have been made up to now: 17190 ± 140 BP6 (GrN-1632), 16100 ± 500 BP (Sa-102), 15516 ± 900 BP (C-406), 9070 ± 90 BP (GrN 3184), 8660 ± 360 BP (Ly-1197), 8510 ± 100 BP (GrN-1182), 8060 ± 75 BP (GrN-1514), 7510 ± 650 BP (Ly-1196). The results can be divided into two main groups: a younger one with a mean of 8380 ± 60 BP (6430 ± 60 BC) and an older one with a mean of 17070 ± 130 BP (15120 ± 130 BC). About nine thousand years lie between both."
Michael Rappenglück (U. Munich), The Pleiades in the Grotto of Lascaux (1997)

^n11  The web page The Tragedy of Lascaux. notes the damage and degradation of the cave art of Lascaux.

Announcing the new website

This website describes the Creation Narrative of Science—a fairly complete narrative only within the past fifty years—and compares it point by point with the Bible's Creation Narrative, primarily presented in Genesis.

The comparison is done by asking short questions such as:

• Why does Day One of the Genesis account begin with the creation of light?

• What does it mean that the earth was without form and void in the verse before Day One?

•How did the dry land of Day Three appear out of the oceans?

This website is still under construction, but it is pretty complete through the first half of Day Three—the formation of dry land. I think you will find the remarks and conclusions surprising and in some cases that they give new insights into the nature of the Genesis narrative. Work is continuing on the remaining parts of the Genesis narrative.

The provides background and additional information for the matters that the website discuss.

David C. Bossard
November, 2015


Part I    Genesis 1: Creation of the Universe (HTM - Slides and Text) Audio  PPT

Part IIA   Genesis 2: Creation of Bacteria (HTM - Slides and Text)  Audio-A  Audio-B  Audio-C  PPT

Part IIB   Genesis 3: Creation of Eukaryotes (HTM - Slides and Text) Audio  PPT

Part III     Genesis 4: The Creation of Man (HTM - Slides and Text) (Audio not available) PPT
              Supplementary Lecture: A Sky Map at Lascaux Cave (HTM - Slides and TextPPT


Part I -- Day One to Day Four (HTM - Slides and Text) PPT 

Part II -- Day Five and Day Six (HTM - Slides and Text) PPT 
Part III -- The Creation of Man (HTM - Slides and Text) PPT 


Norbert Aujoulat, Lascaux -- Movement, Space, and Time (2005) available on-line.
The Pleiades in the Grotto of Lascaux (1997) (pdf). This lists the carbon dating results cited in note 6 above.
Gary D. Thompson, Ice-age star maps (2012).

mailboxAny comments or suggestions are welcome. Please email:

   Astronomy web page  

Update April 14, 2016 The Lascaux Sky Chart