Come to Energy Day for a fun look into the future (and for funnel cake)!

What do funnel cakes and energy have in common?

That’s not a question most people ask. Thankfully there’s an easy answer and that’s Houston’s Energy Day this Saturday, Oct. 17 from 11 a.m. to 4 p.m.! Houston’s Energy Day is the largest free family festival focused on STEM (Science, Technology, Engineering and Math), and they also have funnel cakes for sale! It’s a huge festival down in Sam Houston Park near the Heritage Society Museum.


You can expect lots of awesome booths with fun activates and giveaways, and something fun for everybody. At the Navy booth, you can drive an underwater remotely operated vehicle (ROV) around a swimming pool. You can explore the interior of a NISSAN Leaf electric car. NASA will be on-site for cool giveaways, and both the Houston Rockets and the Houston Astros will have booths, so you can shoot some hoops and play a game of catch (though probably not at the same time).


In addition to all the fun activities, there will be an award ceremony for the winners of several contests that have been going on during the year, such as The Houston Geological Society/Houston Museum of Natural Science/Consumer Energy Alliance Art, Essay & Media Contests. Winning students and teachers will receive scholarship money and a photo holding the big check.

Art Essay and and Media Contest

Live music will play between the award ceremonies. Alongside all the festivities and funnel cakes, our museum will be there, of course! I’ll be playing with a Van de Graaf generator (shocking I know), we’ll have a cast of some dinosaur bones for you to touch, and much, much more.


So sleep in that Saturday and in the late morning, head down to Sam Houston Park for a free, fun-filled festival! See you there!

In the meantime, take a look at the rest of these other images from Energy Day in previous years.



Legend of the Peg Elves: Boy Scout Overnights offer a glimpse into museum folklore

The lights in the Morian Hall of Paleontology brighten and illuminate the Tyrannosaurus rex. The immersive soundscape in The Farish Hall of Texas Wildlife comes to life. The periodic table powers on in the Welch Hall of Chemistry. And the peg elves emerge.


When the lights go out in the museum, the exhibits seem to come to life. Legend has it this is when the peg elves emerge. Photo by Jason Schaefer.

That’s right. As the museum gears up for another day of exploring, learning, and excitement, the peg elves at the Houston Museum of Natural Science begin to stir. They have an important job to do. They are the protectors of the pegs.

The Foucault Pendulum is an icon at HMNS, just outside the Wiess Energy Hall. If you’ve ever found yourself walking through the exhibit halls and suddenly heard an uproar of cheering, then you know it happened; the pendulum has finally knocked over one of the wooden pegs. This happens once every 12 to 13 minutes and has captivated museum audiences for decades with its ability to demonstrate the Earth’s rotation. You can hear the disappointment when visitors feel certain the pendulum is going to knock down a peg, but it swings ever so slightly by it. It’s something I remember watching intently as a child. You root for the pendulum to mark the passage of time by knocking down one of those innocent pegs. It’s the spectator sport of HMNS.


The Foucault Pendulum outside the Wiess Energy Hall demonstrates the motion of the Earth as it rotates. It takes about 13 minutes for the pendulum to knock down a single peg, and it changes direction as our planet rotates beneath it. Photo by Jason Schaefer.

The kids who spend the night at the museum often ask us a lot of questions about the inner workings of the museum. Frequently, they want to know “How do you get those dinosaurs in here?”, “Does everything come to life at night?” and “Who sets all the pegs back up?” That’s when we tell them about the magical yet elusive HMNS peg elves.

Scotland has the Loch Ness Monster. The Himalayas have the Yeti. HMNS has peg elves. The peg elves are bearded creatures who inhabit the innermost workings of the museum. They wait in the depths of the museum for the pendulum to swing back and forth knocking each peg down. The sound of the peg clattering on the tile is music to their ears. It calls to them. It’s their mission and purpose to set those pegs back up.

Scanned Document

This composite sketch was created using eyewitness reports of the peg elves over the years. Reports identify the elves as typically wearing Santa hats and sunglasses, having pointy ears and beards, and reaching heights no taller than six inches.

Early in the morning before the first visitor enters the museum, the peg elves get to work. They move quickly and scamper over the walls surrounding the pegs. They place each peg with precision. The young elves observe with watchful eyes as the elders re-position the pegs. The physics of peg positioning is an art, so it’s only after a dutiful mentoring period that the younger elves are permitted to assist with the pegs. Young elves dream of the day they’re able to prop a peg up on their own. It’s a rite of passage in peg elf society.

After all the pegs are in place, the peg elves return quickly and quietly to their museum hideouts. They wait in the wings to hear that collective cheer as the pendulum swings. The peg elves know that it means there will be more work for them in the morning. After all, they are the guardians of the pendulum, the protectors of the pegs.

Peg Elf Footprints

Here you can see where we’ve successfully tracked a group of peg elves. The tiny footprints are evidence of their presence at HMNS.

Interested in sneaking a peak at the HMNS peg elves for yourself? Visit our Overnights page for information on how you can spend a night at the museum and get a glimpse of these mysterious creatures in the morning hours!

If you’re a Cub Scout or Webelos, register for our Scout Overnight on Oct. 9! You’ll get a chance to explore the museum after hours, see a Burke Baker Planetarium show and sleep in one of our renowned exhibit halls! Visit Scout Overnights or email us for more information!

Google gets it. Celebrate Léon Foucault’s 194th birthday by sharing your swinging HMNS memories!

If you’ve yet Googled today, you may have noticed a lovely homage to Léon Foucault, the famous French physicist best known for inventing the Foucault pendulum (that ever-popular swingy thing at HMNS).

The Foucault Pendulum gets the Google Treatment!

The Foucault Pendulum has long been one of the most memorable areas of the Museum, even if some people (this girl) lack the patience to actually watch the pendulum kick over a peg.

When a peg does go over, there are inevitable cheers. As the pendulum swings, it moves clockwise with the Earth’s rotation, knocking over one peg approximately every 15 minutes. Although the pendulum appears to be traveling around the circle, it’s actually the earth that moves, making this exhibit a perfect visualization of the earth’s rotation.

(Foucault himself said it a little less simply, like this: T = 24/sin q where T equals the amount of time to make one complete revolution and q is the latitude of the pendulum.)

We scoured the interwebs (as we are wont to do) to gather some of our favorite photos of patrons standing enrapt around the pendulum.

Have your own photos or memories to share? Hit us up on social media!

A Short Biography of the Foucault Pendulum.

When you walk into the Wiess Energy Hall, the very first thing you see is our Foucault pendulum.

It is a metal ball suspended by a cable that swings back and forth encircled by pegs. Children and adults will run through the rest of the museum, reach the pendulum, and wait with baited breath to watch a peg topple. When one of the pegs finally falls, you can hear a cheer erupt from the area. It is one of the most memorable parts of the museum. As the pendulum swings, it moves clockwise knocking down pegs as the Earth turns. It swings back and forth, back and forth (you are getting sleepy).

Foucault Pendulum
Foucault Pendulum at the Houston Museum of Natural Science

It is interesting to sit around the pendulum and listen to people try to explain it.

Some will talk about how it is a clock.  Others will put the time between pegs being knocked down between 10 minutes and 1 hour.  Our pendulum knocks down a peg on an average of every fifteen minutes. While the pendulum looks like it rotates around the circle, it is the Earth that is rotating and the pendulum that just swings. The pendulum is a visualization of a rotating Earth. To describe it in a different way, T = 24/sin q where T equals the amount of time to make one complete revolution and q is the latitude of the pendulum. At least that’s what Foucault said.

Star TrailsCreative Commons License photo credit: monkeymanforever

Leon Foucault was born in Paris (France, not Texas) on September 18, 1819.

As a young boy he did not show an inclination towards science or study.  In fact his teacher considered him lazy because he did not turn in his work. He did, however, enjoy building mechanical devices, such as a small steam engine and a telegraph, and tinkering.  He entered medical school to become a surgeon, but found that he fainted at the sight of blood.  Instead of becoming a blindfolded surgeon, he switched to physics. 

At the age of 25, not having learnt anything at school nor from book, enthusiastic about science but not about study, Léon Foucault took on the task of making the work of scientists understandable to the public and of passing judgment on the value to the work of leading men of science – J Bertrand, Éloge historique de Léon Foucault.

Foucault proved his worth in being able to take mathematical proofs and construct a mechanical proof, his pendulum being one of those.

He also constructed a device to prove that light moves slower through water than air. The mathematics describing the proof had been around for over a decade, but Foucault was the first to prove that it worked. His first pendulum on public display opened on February 3, 1851 in the Paris Observatory (again France, not Texas). Instead of knocking down pins as the pendulum moved, the first Foucault pendulum drew in sand.  He also invented the gyroscope, which stays in place as the Erath moves around it. This invention has proved essential for planes, space craft, and even the Hubble Telescope.  

Hubble Space Telescope
Creative Commons License photo credit: NASA Goddard Photo and Video

After he came to power, Napoleon III, an amateur scientist, created a job for Foucault at the newly named Imperial Observatory. There, Foucault developed his knife edge test to measure the conic shape of mirrors. This led to a more constant quality of lenses for use in telescopes.  He died on February 11, 1868 from multiple sclerosis.  His legacy lives on today.  He has an asteroid named in his honor. But he is honored around the world by his plethora of pedula that swing to and fro, showing people that the Earth keeps on spinning.