It’s Baktunalia! Astronomy VP Carolyn Sumners on why Dec. 21 is cause for celebration, not wild imagination

December 21, 2012: It’s not the End of the World — it’s the Baktunalia! It’s time for a celebration, not an apocalypse.

Here are the facts: The Maya long count calendar will go from to as we go from December 20 to December 21, 2012. So December 20 is New Baktun Eve and December 21 is New Baktun Day.

(FYI for those who like numbers: The five digits of the Mayan long count are base 20, except for the second number from the right, which is base 18. Our numbers are base 10. We have ones, tens, hundreds, and thousands. The Maya long count has kins, winals, tuns, katuns, and baktuns. For the Maya, a day is called a “kin.” Twenty kins make a winal. Eighteen winals, or 360 kins, equal a tun, making the tun about a year long. Twenty tuns make a katun and 20 katuns equal a baktun. Thirteen baktuns is just over 5,125 years.)

The Roman Saturnalia festival also occurred at this time — a celebration featuring food, gifts, and celebrations around the Winter Solstice. Early Christians could celebrate Christ’s birth on December 25, hiding their event within the Saturnalia festivities. Hence, I’m calling this year’s rare event a Baktunalia!

See 2012: Mayan Prophecies at the Burke Baker Planetarium

Did the Maya calendar-makers over 2,000 years ago plan for their long-count calendar to reach the 13th Baktun on December 21? This is possible, but it seems unlikely. However, December is the Winter Solstice, a day the Maya recognized as the shortest day and longest night of the year — the day when the sun rises furthest in the southeast, sets furthest in the southwest, and makes its lowest and shortest path across the southern sky in the Northern Hemisphere. The Maya astronomers observed the sun on the winter solstice to document its southernmost rising and the promise that the sun would now start moving northward. There would be another spring and a new growing season.

Unlike the Internet doomsday prophets, science does not support an apocalypse in 2012. Solar activity maximum is happening in 2013. Thus far, all natural disasters in 2012 have been within the normal range of activity on a geologically active planet with dynamic weather patterns.

But there is one interesting astronomical alignment. On December 21, the sun will reach its lowest point in the sky for the Northern Hemisphere while it is in front of a dark rift in the Milky Way and directly between Earth and the Milky Way Galaxy’s center. This alignment has been in place for several years, but is often cited by the doomsday prophets. The black hole near the galactic center has the same effect on us today as it does on any day. This alignment makes no difference. Nor is it significant on December 21. After all, the sun is its strongest on this date south of the equator.

Lost in all the apocalyptic talk are the very significant achievements of the Maya regarding both time-keeping and astronomy. In the Burke Baker Planetarium, we have a show called Mayan Prophecies that visits four classic Maya cities (Uxmal, Chichen Itza, Tikal, and Palenque), as they would have looked over a thousand years ago. At Uxmal, we see a Maya astronomer watching the sun’s rays entering the Temple of the Magician just two 20-day months before the sun would stand overhead and the rains would come. After this event, the astronomer could prepare farmers to plant their corn and the king to plan festivals.

At Chichen Itza, the feathered serpent god called Kukulcan would climb down his pyramid, El Castillo, on the first day of spring. Astronomers would then know when to have festivities with human sacrifices, trading human blood for the coming rains — all to appease Kukulcan and the rain god, Chaac. We actually show this sacrifice (tastefully) in the full dome and very up-close in the Mayan Prophecies planetarium show.

At Tikal (located in the lowlands of Guatemala), the astronomer would climb his pyramid, now called Temple 4, to watch the rising sun on December 21. When the sun rose over Temple 3, it marked the winter solstice. After this date, the astronomer knew that the sun would rise more to the north each day and that the rainy season would come again.

At Palenque, there are inscriptions inside major temples featuring trees for the seasons. The great King Pacal supposedly rose and journeyed to the heavens on December 21. Inscriptions at Palenque also explain the beginning of the long count cycle on a date we know now as August 13, 3114 BCE. Three temples at Palenque symbolize the three hearthstones of creation, with a central fire lit at the beginning of the current long count cycle. There are also three stars in our constellation Orion that represent these hearthstones.

For all their predictive power, the Maya astronomer could not foresee his own apocalypse, which happened over a thousand years ago. A combination of factors adding to decades of drought brought famine to the Classic Mayan cities. This great civilization, that had measured time and predicted the rains, collapsed and its people returned to the rainforest and mountains. The story of the Maya people is perhaps a greater predictor of the challenges we face in 2012 and beyond.

Fascinated? Discover how the Maya aligned their pyramids and temples to watch their sky gods and used interlocking calendars to record the past and predict the future in our Mayan Prophecies lecture. Dr. Carolyn Sumners will share how archaeological, historical and astronomical records were pieced together to learn more about the Maya. This lecture includes a viewing of film 2012: Mayan Prophecies. For lecture tickets, click here.

Labor Day! Fun For The Long Weekend At HMNS

Monday is Labor Day – and you know what that means, right?


In case you’re wondering how to fill the long hours between Friday afternoon and Tuesday morning, here’s a list of the top ten weekend experiences you can have with the family at HMNS all weekend long.

That’s right – we’re open MONDAY! Because we’re here for you. 

10. Come And Take It!

A look at the stunning variety of fascinating artifacts from Texas’ rich history, that is.

Come And Take It
The Come And Take It Cannon!
See a full set of photos from the exhibit on Flickr

Texas! The Exhibition closes at 5 pm on Monday, Sept 5 – so don’t miss your last chance to see Santa Anna’s spurs, Davy Crockett’s violin, the Davis Guards Medal and many other objects from a huge swath of Texas history – from prehistoric cultures to the Spindletop oil gusher.

Preview the exhibit with our blog series on Texas History! (And see how you can win free tickets to see the exhibit closing weekend!)

9. Ramble through Borneo with Orangutans

And while you’re at it, explore Tsavo with young elephants.

Born To Be Wild
The cuteness! See it this weekend in Born To Be Wild 3D at HMNS!

Born To Be Wild 3D is a fascinating, entertaining and heart-warming film chronicling the efforts of two pioneering women to save orphaned animals.

Time Out New York says “The kids will squeal with delight.” We think you probably will, too.

8. Discover The True Meaning of Mayan Prophecies 

2012: Mayan Prophecies
2012: Mayan Prophecies in the HMNS Planetarium

Worried about 2012? Explore the Mayan culture in this new planetarium film. Learn why Dec. 21, 2012 will be just another day, but the Mayan culture’s true contributions to civilization are unique and fascinating.

7. Solve A Crime!

If watching CSI makes you think you think “I could do that!” – this exhibit is for you! Study fingerprints, chromatographs, DNA, insect lifecycles, tire marks, hair analysis, thread comparison, and handwriting analysis to catch the culprit!

Crime Lab Detective opens at the Houston Museum of Natural Science at Sugar Land on Saturday, Sept. 3!

6. Watch A Butterfly Enter The World!

Cockrell Butterfly Center

Our butterflies flit through a three-story, glass enclosed rain forest habitat – and it’s a showstopper of the large-scale variety. But you shouldn’t miss the Hall of Entomology on the upper level – where you can watch butterflies emerge from their chrysalides daily. It’s a quiet moment of tranformation, rebirth and wonder that everyone should experience.

5. Discover a Modern-Day Dragon

Think all dragons breathe fire? Some just flash it – including The Dragon, one of the world’s most famous mineral specimens.

The Dragon | HMNS Mineral Hall

It just so happens to be part of our collection – on permanent display in the Hall of Gems and Minerals, along with literally hundreds of the world’s finest gems and minerals. Hundreds. 

4. Develop An Intense Desire To Wear This.

Ancient Ukraine Exhibit at HMNS
Preview the entire exhibition in this set of photos on Flickr.

If you’ve followed our advice on #4, you’ve likely whetted your appetite for gold. And our Ancient Ukraine exhibition (closing Sept. 5!) could be called: Gold! Oh, And Some More Gold. (Except that it also features fascinating artifacts made from many other materials, from the entire 6,000 year history of Ukraine.)

Get an idea of what you’re in for in our curator’s blog series on Ancient Ukraine.

3. Spend Saturday With The Stars!

George Observatory

Long weekends are the perfect time to make the long drive out to our George Observatory. It’s an hour outside Houston, but that means light pollution is at a minimum – and stars are at a maximum.

If you’ve never been, you will marvel  at the number of stars you can see with the naked eye – and the astronomical detail you can view through our Gueymard telescope, one of the largest in the country that’s available for public viewing.

The Observatory is open every Saturday night from 3 – 10 pm. Get Directions and information on Admission.

2. Explore Two Continents

Hall of the Americas

Our Hall of the Americas features cultures from the Inuit in Alaska to the Inca of Peru – go on an expedition through hundred of years of American history and over 2 continents this weekend!

1. Take The Science Fun Home!

The HMNS Museum Store has a metric ton of science ideas and activities to take home – and your purchases always support our science educational programs! Grab the Pocket Starfinder for your Big Bend camping excursion, take the Encyclopedia of Texas Shells on a seashore expedition, or identify what’s fluttering around your own backyard with the Butterflies of Houston and Southeast Texas Guide.

From a Galileo Thermometer to track the summer heat to a Dinosaur Hunter Field Canteen, we’ve got everything you need to close out the summer right!

Here’s to a great long weekend – hope to see you here at HMNS!

Chak Ek’

Page 49 of the Dresden Codex

Have you had a chance to come out and see our newest planetarium show, 2012:Mayan Prophecies?  If so, you’ve enjoyed a fascinating glimpse into an ancient culture known for its astronomy.

The Dresden Codex

Consider, for example, the Dresden Codex, the oldest book known to be written in the Americas.  The best preserved of four ancient Maya writings, this 11th or 12th century document found its way to an owner in Vienna; Johann Götze of the Royal Library at Dresden bought it in from that person in 1739.  (The writing was probably first sent into Europe by Hernán Cortés, conquistador of Mexico.)

The Dresden Codex features tables of eclipses, full and new moons, as well as the times of solstices and equinoxes.  Conjunctions (close alignments of planets in the sky) are noted, as are the times when each planet rises just before or just after the sun.  The Codex devotes six pages to measurements of the positions of Venus.

Chak Ek’

The emphasis on Venus, or Chak Ek’ to the Maya, distinguishes ancient Maya astronomy from that practiced by other ancient cultures.  Of course, people in civilisations all over the world noticed Venus, which outshines everything in the sky except the sun and the moon.  However, other cultures did not consider cycles of Venus as important for time keeping. Let’s look at how Maya astronomers could use Venus as a marker of time.

First, some basic facts about Venus and its orbit.

Venus is the second planet from the sun; Earth is the third. As result, Venus’ orbit is completely inside Earth’s and we see the whole orbit in ‘front’ of us, so to speak. As of May 2011, Venus is in the morning sky, where it has been since November 2010. This means that for the past six months, Venus has been ahead of us on its faster, inner, orbit.

However, we’ll soon see Venus pass around the far side of the sun, making it invisible to us for about a month and a half this summer.  By fall 2011, Venus will have emerged from behind the sun, such that it appears to the sun’s left in our sky.  This makes Venus an evening star, appearing over the western horizon at dusk.  Venus remains an evening star through spring 2012, while it gradually catches back up to Earth, coming back around to our side of the sun. On June 5, 2012, Venus catches back up to us and ‘laps’ the Earth on its faster orbit.  Thus we’ll see Venus quickly drop out of the evening sky in late May and reappear in the morning sky by mid-June.  Venus then remains in the morning sky until it heads around the far side of the sun by March 2013, and the process repeats.

Global radar view of Venus.
Photo taken by NASA

A Venus Cycle

One Venus cycle, as described above, takes 584 days.  Also, as it turns out, Venus completes 13 orbits around the sun in almost exactly eight years.  On a given date in 2011, for example, Venus is where it was in the sky on the same date in 2003, within two days.  These facts enabled the Maya to keep a regular calendar of Venus’ appearances.  For the Maya, each Venus cycle began with Venus’ entry into morning sky, rising just before the sun.  Called the heliacal rising of Venus, this is the moment when Venus is on our side of the sun, having just ‘lapped’ Earth and pulled ahead on its faster orbit.

Maya astronomers also noted Venus’ emergence into the evening sky, but considered that less significant.  After all, Venus becomes an evening star only gradually, taking over a month to emerge from the sun’s glare.  It is also dimmer than average at this time because it is on the far side of the sun from us.  On the other hand, Venus enters the morning sky quite quickly and dramatically, appearing noticeably higher each morning for several days.  And since Venus is closest to us at that time, it is also brighter than average.  Upon observing a heliacal rising, Maya astronomers knew the next would occur 584 days later.  And they knew to expect another such rising of Venus during the same season about eight years later.

The Only Planet Named for a Goddess

Due to its brillance, cultures around the Mediterranean associated Venus with love and beauty.  That’s why Venus is the only planet named after a goddess.  At one time, the Greeks distinguished the evening star Hesperus (Latin ‘Vesper’) from the morning star Phosphorus (Latin ‘Lucifer’), but they were both names for Venus.

Maya also distinguished the evening star (Lamat) from the morning star (Ah-Chicum-Ek’).  For the Maya, either appearance of Venus was a harbinger of evil–particularly the morning star.  This made Venus’ sudden appearance at dawn a good omen for someone wishing to wreak destruction.  Accordingly, Maya often scheduled attacks on rival cities to coincide with the heliacal rising of Venus.  One such attack, which the Maya called a ‘Star War,’ is depicted in our show.

Looking For Venus Today

If you want to observe Venus today (May 2011), you need to rise before dawn and face east.  An interesting gathering of four planets, in progress for much of the month, still continues.  As I write this, Venus and Mercury have passed Jupiter and are approaching Mars.  Venus and Jupiter are about eight degrees apart with Venus to the lower left.  They far outshine everything else but the sun and the moon, so those two planets are easily noticeable well into twilight.  Mars and Mercury appear to either side of Venus  and are much dimmer.  Right now, Mercury is to the lower right of Venus with Mars to the right and a bit above Venus. Today, Venus is within one degree of Mars.  Mars is above Venus, Mercury below.  The alignment of Mercury, Venus, and Mars was closest on the morning of May 21.

After this, Mercury quickly exits the scene while Venus gets lower and lower in the pre-dawn sky throughout June, until it is lost inthe sun’s glare by July.  2012, however, offers some spectacular views of Venus.  In spring 2012, Venus appears as high as possible in the evening sky (as it did in 2004 and will do again in 2020). That particular evening apparirion ends June 5, 2012, as Venus aligns so well with the Earth and sun that it appears as a dot on the sun’s disk.  That transit of Venus will be the last such event in the lifetime of anyone alive today.

Hopefully, none of this will be taken as a sign to sacrifice or invade others.

What do you know about 2012? [Quiz]

To celebrate our new Planetarium Show 2012: Mayan Prophecies, we are testing your knowledge of the significant Maya date of December 21, 2012. How much do you know about this important day?

Are these statements TRUE or FALSE?

1. Dec. 21, 2012 marks the end of the longest Mayan time cycle.

2. The Aztecs knew about 2012.

3. In 2012, solar storms will burn the surface of the Earth.

4. Dec 21, 2012 is a significant celestial date.

5. The Maya used the 26,000-year precession cycle to predict events in 2012.

6. There will be a cataclysmic event in 2012.

7. An impending pole shift will tear the Earth apart in 2012.

8. There is a special alignment of the sun in front of the Milky Way galaxy on Dec. 21, 2012.

9. A rogue planet, such as Nibiru or Eris or Planet X, is going to destroy the Earth in 2012.

10. A geomagnetic reversal in 2012 will devastate the planet.

11. A “global awakening” is coming in 2012, leading to a societal transformation.

12. The Earth will pass through the Galactic plane.

2012: Mayan Prophecies
A scene from 2012: Mayan Prophecies, Now Showing in the HMNS Planetarium!


1. Dec. 21, 2012 marks the end of the longest Mayan time cycle.
TRUE: Dec. 21, 2012 is the beginning of the 13th Baktun in the Maya Long Count. This is a day of celebration, much like Jan. 1, 2000 was for us.

2. The Aztecs knew about 2012.
FALSE: There is no archeological evidence that 2012 was significant to any other MesoAmerican civilization.

3. In 2012, solar storms will burn the surface of the Earth.
FALSE: A massive solar storm could take out a satellite, but cannot reach Earth’s surface. Also sunspot maximum will occur in 2013.

4. Dec 21, 2012 is a significant celestial date.
TRUE: Every year, December 21 is the winter solstice when the sun makes its lowest trip across the sky in the Northern Hemisphere.

5. The Maya used the 26,000-year precession cycle to predict events in 2012.
FALSE: The Maya may have observed slow changes in the sky due to precession, but this cycle was never recorded.

6. There will be a cataclysmic event in 2012.
TRUE: There will be volcanic eruptions, floods, earthquakes, tornadoes, and hurricanes in 2012 – just like every year on our dynamic planet.

7. An impending pole shift will tear the Earth apart in 2012.
FALSE: The poles wander at a speed of about 1 degree per million years.

8. There is a special alignment of the sun in front of the Milky Way galaxy on Dec. 21, 2012.
TRUE: On the winter solstice, the sun is now in front of a dark rift in the Milky Way band, close to the direction of the Galaxy’s center as it has been for several years.

9. A rogue planet, such as Nibiru or Eris or Planet X, is going to destroy the Earth in 2012.
FALSE: Eris is now beyond Pluto. There is no Planet X. The Babylonian Nibiru was probably Jupiter. The Maya only knew Mercury, Venus, Mars, Jupiter, and Saturn.

10. A geomagnetic reversal in 2012 will devastate the planet in 2012.
FALSE: Geomagnetic reversals do happen and we may be overdue for one. These take thousands of years to occur and are not destructive.

11. A “global awakening” is coming in 2012, leading to a societal transformation.
TRUE: Well, 2012 is a presidential election year for the United States and for Mexico and the diamond jubilee of the Queen.

12. The Earth will pass through the Galactic plane.
TRUE: The Earth will cross the Galactic Equator, but in about 27 million years.

Come learn more about Maya culture and their calendar in our new Planetarium show, 2012: Mayan Prophecies, open now.