Home

Film Premiere: Saving the Bay

 

Phaela Peck by Phaela Peck  October 8th, 2009
37.6788056, -122.2880726

The beautiful San Francisco Bay.

Over the last two weeks I have had the opportunity to preview the film "Saving The Bay," as I prepare educational Viewing Guides for teachers. Even though I have called the Bay Area home for many years, I realized through watching this documentary that there is so much I do not know about my own backyard—the Bay. In addition to learning from "Saving The Bay," it has inspired me to explore new areas and to get more involved in restoration efforts. I am hopeful that students will also be inspired by this film and encouraged to go outside and enjoy our magnificent home.

"Saving The Bay," a film by Ron Blatman, is a four-part documentary chronicling the history of the San Francisco Bay. From the formation of the Bay itself to the formation of Save The Bay, this beautiful film tells the story of the Bay through striking images and knowledgeable voices. Complete with impressive animation, historical video footage and a lovely musical score, "Saving The Bay" offers an expansive overview of a vibrant San Francisco Bay region and how it came to be what it is today.

The first episode, "Saving The Bay," details the history of the San Francisco estuary and the first people to inhabit the region. "Harbor of Harbors", tells the story of San Francisco Bay’s dramatic transformation following the California Gold Rush. The third episode, "Miracle Workers," focuses on the engineering and industrialization of the Bay. "Bay in the Balance" shares how the Bay was saved and plans for the Bay’s future.

"Saving The Bay" is a great educational tool for teachers and alternative educators alike. This film presents a plethora of information in an engaging manner and covers many California State Science and Social Studies Standards for grades 4-12. Furthermore, upon watching parts or all of "Saving The Bay," students will develop a deeper understanding of their local environment and perhaps be motivated to participate in the on-going effort to save the Bay.

The first two episodes premiere on KQED Channel 9 on Thursday, Oct. 8 at 8pm. Click here to find additional air times/dates and to find out what else "Saving the Bay" has to offer.

Abandoned Boats

America’s Last Whaling Station (TV)

Cleaning Up Hunter’s Point

Elk Return to the Bay Area

From Salt Ponds to Wetlands

Fur Seal Pup Rehab

Ice Age Bay Area

Journey to the Farallones

Legacy of Salt

Mercury in the Bay – Part 1

Mercury in the Bay – Part 2

Redesigning the Bay

Rising Seas

San Francisco Bay Debris

San Francisco Bay Invaders

Sea Lion Rescue

Sharks of the San Francisco Bay

The Return of the Canal

Waste Water Woes: Sewage Spills in the SF Bay

Web Extra: Citizen Science – Mud Snails

Wetlands Time Machine

What’s Killing the Sea Otters?

Science Event Pick: Golden Gate Raptor Observatory’s 25th Anniversary

 

Kishore Hari by Kishore Hari  September 10th, 2009
37.8254839, -122.4994171

Every fall, 30,000 raptors and hawks migrate across the Bay Area in a fantastic display.Every fall, 30,000 raptors and hawks migrate across the Bay Area in a fantastic display. Most stop for a quick snack in the Marin Headlands before moving on to their winter homes. Bay Area scientists and volunteers have been using the opportunity to conduct counts, as raptors have long been seen as indicators for ecosystem health. The Golden Gate Raptor Observatory, now a program of the Golden Gate Parks Conservancy, was set up 25 years ago as the first bird monitoring system in California. Anyone that visits “Hawk Hill” during this time can attest to mass migration; Upwards of 1000 birds are seen per day during the peak. To my amazement, the observatory is almost fully run by volunteers; there are only 3 full time employees compared to over 300 volunteers. Clearly, this is one of the most successful citizen science projects in the Bay Area.

In celebration of the 25th anniversary, there are a number of interactive events and talks scheduled over the next month.

Hawk Talk and Banding Demo

Where: Hawk Hill

When: Sat 9/12, Sun 9/13, Sat 9/19, Sun 9/20, Sat 9/26 12 Noon – 2 PM

Cost: Free

Details: At these Hawk Talks, a GGRO volunteer gives an hour-long talk about hawk monitoring, migration, and identification using photos and other props. Then at 1 PM a newly banded wild hawk is shown to the crowd, a volunteer talks about GGRO's banding program, and the hawk is released.

GGRO Open House and Raptor Fest!

Where: Ft Cronkhite at Rodeo Beach

When: October 24th and 25th, 10 AM-4 PM

Cost: Free

Details: Scientific Displays, Radiotelemetry Demonstrations, Live Non-releasable Raptors, Kid Crafts, GGRO 25th Anniversary Product Sales, Visits to Hawk Hill, Banding Demonstrations, and Raptor Art. On Sunday only – Speakers from UC Davis, SF State University, UC Berkeley presenting results of their research with GGRO.

Celebrate Raptors—A Series of Raptor Biology Talks

Satellite-Tracking Peregrines throughout the Americas

Where: San Francisco Zoo

When: Thursday, September 10th 7-9 PM

Cost: $3-$5 suggested donation

Falconiformes Discovery: Field, Lab, and Conservation

Where: California Academy of Science’s Nightlife

When: Thursday, October 15th 7-9 PM

Cost: $12

Eagle Quest:  To See All the World’s Eagles

Where: Mission Blue Chapel, Cavallo Point

When: Wednesday, November 18h 7-9 PM

Cost: $3-$5 suggested donation

Science Event Pick: The Long Quest for Health Care Reform

 

Kishore Hari by Kishore Hari  August 24th, 2009
37.789251, -122.400811

This week's local science event pick focuses on health care reform.A recent PBS News Hour with Jim Lehrer opened with this quote from President Barack Obama: "There are examples of how we can make the entire health care system more efficient. …What works? The Mayo Clinic. The Cleveland Clinic. Geisinger. Kaiser Permanente. There are health systems around the country that actually have costs that are as much as 20 percent or 30 percent lower than the national average and have higher quality. What is it that they are doing differently from other systems?"

The idea for Kaiser was developed by Dr. Sidney Garfield way back in 1933. He established a prepayment health plan for 5000 workers building the Los Angeles Aqueduct in the Mojave Desert. Workers paid about a nickel a day to receive full medical care from Dr. Garfield. He emphasized prevention and early treatment to prevent more serious problems later.

Fast forward to today, the same issues of prevention to keep down costs are still being discussed today. Certainly, HMOs are not without criticism, but it is certainly a compelling story to trace the development of the modern system from a place of preventative care. Plus, it will be a relief to have a healthcare discussion without all the yelling.

Tom Debley is the author of The Story of Dr. Sidney R. Garfield: The Visionary Who Turned Sick Care into Health Care, the theme of his talk will be "The Long Quest for Health Care Reform: A Bay Area Doctor's Belief in Health Care as a Right." He will trace the story of Dr. Garfield's life because so much less is known about him than his co-founder, Henry J. Kaiser.

The Long Quest for Health Care Reform: A Bay Area Doctor's Belief in Health Care as a Right

When: Tuesday, August 25th 2009

Where: Commonwealth Club, 595 Market Street 2nd Floor

Cost: $8 members, $15 non-members, Tickets

Science Event Picks: The Low Carbon Diet, August 9 and 10

 

Kishore Hari by Kishore Hari  August 6th, 2009
37.7553926, -122.4198588

Amazing what foods you can find in your own– and your neighbor's– backyard. Photo credit: Iso Rabins of ForageSF "What happens on your plates represents your most important engagement with the natural world and the biggest impact you have on climate change." – Michael Pollan

Considering that I work from home, don't fly very often, and walk or take mass transit most places, I bet Michael Pollan is especially right for me. Last June, QUEST had a radio piece on a low carbon diet with tips to lower your CO2 impact, but my inner scientist needs some data. That's when I found the Carbon Foodprint Calculator.



Here's what I ate yesterday:

My wife usually nags me about my diet, but I think I did pretty well yesterday! (excepting those diet cokes) My carbon foodprint was 2641 CO2e points. Each point represents 1 gram of CO2e equivalent or in my case 5.8 lbs of CO2e. Now this is calculator certainly has limitations (mentioned in their FAQ section), but it is a satisfying comparison study. The site claims that most Americans have room to cut their carbon foodprint 25%. Not easily done, but luckily we have help in the Bay Area.

This weekend, Iso Rabins, founder of ForageSF, is taking an intrepid crew out to learn about foraged foods (virtually zero in carbon foodprint if foraged locally). He'll teach you how to identify wild edibles all around you, from wild fennel to mallow to nettle. Many of the plants we see everyday can be consumed on the spot (although better after a quick rinse). After taking a collecting walk, he'll cook up some snacks that includes some of what was foraged.

On Monday, Chef Laura Stec and climatologist Eugene Cordero cook up some Cool Cuisine, with a discussion of their new cookbook focusing on low carbon recipes. Cordero presents research on the energy efficiency of our food system and the relationship to our changing climate and then Chef Laura provides some practical cooking tips for low carbon foods without sacrificing flavor. For those who can't make the event, you can watch their presentation last month at the PARC Forum.

Guided Foraging Tour with ForageSF & TransportedSF

When: Sunday, August 9th 12 PM – 7 PM

Where: Meet at Papa Toby's Revolution Café, 3248 22nd St, SF

Cost: $35, Tickets

Environmental Action through Eating: Best Bang for the Buck

When: Monday, August 10th 6 PM – 730 PM

Where: Commonwealth Club, 595 Market St, 2nd Floor, SF

Cost: $8 members, $15 non-members, Tickets

Good night, sleep tight, don't let the bed bugs bite!

 

Cat by Cat  July 22nd, 2009
37.769593, -122.46632

Bed bugs are small, but not invisible. (photo credit)
Before this past week, I really did believe this was a nursery rhyme. Bed bugs were a mere fluff equivalent to Miss Muppet and her tuppet and the eensy weensy spider climbing up the water spout. I was re-introduced to bed bugs recently by my neighbor who had his whole studio infested. He had dark circles under his eyes and a somber face when he warned me about the little bugs.

So I closed my door and did what I always do when faced with something I don’t know about, I Googled it. There is a species known as the Cimex lectularius that makes humans their host of choice. All Bed Bugs feed on blood and come out at night, as they are often averse to sunlight. Their most preferred feeding time is an hour before dawn when most hosts are in their deepest sleep. They are attracted by exhaled carbon dioxide as well as the heat a human body gives off. When biting, they inject two hollow tubes. One tube injects saliva into the host which is full of anticoagulants and anesthetics while the other tube withdraws the blood. This allows the blood to thin and flow freely without disturbing the host. Most often it is several minutes or hours later when a person will feel a bed bug bite, usually because of intense itching caused by a reaction to the agents injected.

Though itchy, Bed Bug bites do not appear to carry any pathogens or diseases. Bed bugs prefer to come out and eat every five to ten days but can go up to a year without feeding. Well fed bed bugs will live up to nine months but those that go dormant due to lack of food can live upwards of eighteen months.

Many people think bed bugs are not visible. They're just small: 1/8 to 3/16th of an inch long, about the size of a lentil. They are also wingless, flat, oval and reddish brown in color. After feeding, they take on a more intense red color due to the blood they just injested. Newly hatched nymphs are translucent and only take on the brownish-red color when they begin molting.

Bed bugs are also very well traveled and fare well in large cities. Chicago and New York have seen a great deal of infestations, in part due to international travel. The New York Times recently posted an article about best ways to deal with bed bugs. Locales of choice include mattresses, couches, and furniture near their hosts, often found in hotels, motels, hostels and apartment buildings. Given their small size, they can hide easily in seams, cracks and folds – even in a picture frame or a battery compartment of a clock! If a suitcase is laid on an infested bed in a hotel, it is easy for bedbugs to hitch a ride. The best prevention to take is to check furniture in hotels and put luggage up on luggage racks and check everything upon returning home.

As it turns out, infestations can also be caused by second-hand furniture. My apartment building got its bed bugs when a tenant brought in furniture he found on the street. To my great relief, after three sleepless nights, a great deal of laundry and bagging up clothes and pillows, my apartment was inspected and found to be clean. But I have definitely changed my routine. I have been bagging storage items in plastic and I put white sheets on the bed to be able to see bed bugs if they come in. I am also buying a mattress bag to protect my mattress.

In cities like San Francisco, international guests now include bed bugs. And they prove to be a hard visitor to get rid of!

Bay Bridge Rising

 

Dan Gillick by Dan Gillick  July 9th, 2009
37.804556, -122.3711

Sketch drawing of the proposed San Francisco-Oakland Bay Bridge (1913) from Overland Monthly, April 1913.

The Bay Bridge will be closed from September 3rd at 8:00 p.m. until the 8th at 5:00 a.m. During these 105 hours, Caltrans will perform an "essential and unprecedented construction feat."

It turns out there was a lot I didn't know about the Bay Bridge. Its official name, for example is not the Bay Bridge. It's "The James 'Sunny Jim' Rolph Bridge," after the California Governor who died in 1934, two years before the bridge opened (The Golden Gate Bridge opened 6 months later). Around 280,000 vehicles traverse the bridge every day—nearly $7 in bridge tolls per second; The Yerba Buena Tunnel that connects the eastern and western segments is the world's largest diameter bore tunnel; Much of the eastern span is supported by old growth Douglas Firs, driven into firm mud.

As construction grows increasingly noticeable, the new eastern section rising out of the bay, more people are wondering: How will it attach? What happens to the old bridge? What's with the retrofit of the western suspension? And what is this unprecedented feat of construction happening over Labor Day weekend?

The construction website, baybridge360, just received a Webby award in the Government category, and is worth a visit. Videos and slide shows are overlaid on a satellite image of the bay and provide answers to these and other engineering questions. There's a bit of Troy McClure style narration, epic synthesizer for the construction scenes, and techno pop for the fast-forward time lapse photography. At one point, the “Governator” dons a pair of terminator sunglasses for a ceremonial blowtorching.

The new site may be sleek, but some of the most interesting information is buried in the old stalwart: baybridgeinfo.org. The western span's retrofitting, completed in 2004, added some 17 million pounds of structural steel, and included new rollers between the roadway and the bridge supports. The new eastern segment (slated for rebuilding since a section collapsed in the 1989 Loma-Prieta earthquake) will include the world's longest Self-Anchored Suspension (SAS) bridge, connected to a pier-supported "Skyway" (elevated roadway over a mile of mudflats), sloping down to the "Oakland Touchdown."

The 2,047-foot asymmetric SAS will be supported by a single steel tower, embedded in rock, rising 525 feet above sea level. While most suspension bridges use a pair of cables, the new SAS employs a single cable, anchored on the east side, wrapped over and around the tower, and down to the west. The Skyway is supported by a set of steel pipes, driven 300 feet into deep bay mud by a massive hydraulic hammer.

Amidst the construction clamor, considerable attention is afforded to local wildlife. Dense columns of air bubbles helped dissipate shockwaves from the hammering to ease construction-related stress on local fish. For the birds, platforms under the new east span provide cormorant nesting habitat, and the crew is building a 500 square-foot island for the pleasure of the snowy egret and ruddy turnstone. And at the Oakland touchdown, a turbidity-controlling curtain was installed to protect eelgrass, which in turn serves as a filter, improving water quality.

So consider all this next time you lament the $4 bridge toll. The original 1936 toll, collected in both directions, works out to over $20 in 2009 dollars. The bridge is scheduled for completion in late 2013.

Calling all Psocoptera! Science Book Clubs in the Bay Area

 

Kishore Hari by Kishore Hari  May 22nd, 2009
37.7697, -122.466

I admit it, I watch way too much television. Some good television (KQED QUEST for example), but mainly bad television: American Idol, Amazing Race, pretty much anything on the VH1 channel. My brain was turning to mush.

After some cajoling from the wife, I trekked down to the library to check out the science section. I was amazed at the bevy of great pop science books. Most are accessible, quick reads on pretty much every science topic under the sun. However, I'm a social creature, I wanted to discuss science books with peers.

A few quick searches and voila! Science book clubs exist right here in the Bay Area (one of them hosted by myself so I'd have more control on book selection). Lively discussion and science books, it's a good combination.

Down to a Science Book Club

Book: "How We Decide" by Jonah Lehrer

When: Monday, May 25th, 7-9 PM

Where: Books Inc, 601 Van Ness @ Turk, 2 blocks north of SF City Hall

Details: Ever had a experience of option paralysis? Like when you are looking at the 11 different types of Cheerios in the cereal aisle? If you're anything like me, decision making is an "interesting" process. Jonah Lehrer tackles the neurobiology of decision making and points out a few ways you may be able to overcome that paralysis. Watch Jonah discuss decision making at the Commonwealth Club or listen to him discuss Choice on RadioLab.

California Academy of Science Book Clubs

Teens Talk Books: Underwater Explorations

Book: Shark Life: True Stories about Sharks and the Sea by Peter Benchley

When: June 6th, 11:00 am in Education Classroom

Where: California Academy of Sciences

Coming face to face with the jaws of a great white shark.  Chasing leaping orcas near Vancouver.  Swimming with hoards of hammerheads in the Sea of Cortez.  Benchley, the author of Jaws, shares his many underwater adventures with sharks and other marine creatures, while helping the reader learn more about these majestic creatures, how to swim with them safely, and why it is vital for us to protect our oceasn.  Join us for a discussion of Benchley's fascinating read!

Reservations: Free with admission to the museum, but participants should call the Naturalist Center at 415-379-5494 to reserve a space.

Bookworms (Adult Book Group): Why Do Oceans Matter?

Book: Sea Change: A Message of the Oceans by Sylvia Earle

When: June 16th, 6:30 pm in the Naturalist Center

Where: California Academy of Sciences

Details: In recognition of World Ocean Day this month, the group will read and discuss noted marine biologist Sylvia Earle's book which is both a plea for ocean conservation and a very personal story of her own lifelong exploration of life in the deep.

Reservations: Free.  Reserve a space by calling 415-379-5494.

This Week In Science Online Book Club – Hosted by TWIS.org

An Ocean of Air: Why the Wind Blows and Other Mysteries of the Atmosphere

Details: Most of the time we hardly notice that we're moving through air. But when a storm system whips it into a whirling mass that grows into a tornado or a hurricane, then the air around us makes headlines. Science consultant Walker (Snowball Earth) presents a lively history of scientists' and adventurers' exploration of this important and complex contributor to life on Earth, from Galileo's early attempts to show that it has weight to the explorations by 20th-century scientists Oliver Heaviside and Edward Appleton of the ionosphere, which acts as a giant mirror bouncing radio waves from one side of the globe to another. Walker provides readers with easy-to-follow discussions of the science behind the discovery that carbon dioxide levels are rising exponentially.

When a Cosmo's More Than a Cocktail: Yuri's Night at Cal Academy

 

Cat by Cat  April 15th, 2009
37.7697, -122.466

Yuri Alexyevich Gagarin, "Columbus of the Cosmos" Last Thursday evening, over 3500 people came to the California Academy of Sciences to help celebrate Yuri. This gathering was not the only celebration of its kind. Two-hundred and eight parties in forty-six countries on eight continents celebrated Yuri's Night between April 6 and 12th of this year.  So who is Yuri and why does he deserve such accolades?

Yuri Alexyevich Gagarin was a Soviet cosmonaut.  He was the first human in space and is often referred to as "the Columbus of the Cosmos".   His spacecraft Vostok-1 orbited the Earth on April 12, 1961 for the duration of 108 minutes.   Yuri's Night, usually celebrated on April 12th celebrates this historic first flight.

Yuri's Night also celebrates another April 12th anniversary notable in the annals of space travel.  Twenty years after Yuri Gagarin's historic flight, the first NASA space shuttle flight, STS-1 was launched into space.  STS is short for Space Transportation System.  NASA names each flight STS with the chronological number after it.  STS-1 was launched on April 12, 1981; the shuttle orbited the earth 37 times during a 54.5 hour mission.

Since 1961, our interest in space and the exploration of its depths has magnified.  Recently NASA launched the Kepler mission.  On March 7th, 2009, the Kepler Mission successfully launched from Cape Canaveral, Florida.  Kepler, which is a specialized telescope, was designed to find the first Earth-size planets orbiting stars within a "habitable zone". A habitable zone is an orbit around a star that would enable a planet to formulate and upkeep an atmosphere and the ability for water to form in pools on the planet's surface.  Liquid water is believed to be essential for the formation of life.  Thus from the nascent flight of orbiting our own Earth, space travels has evolved to look amongst other start.  This progress is certainly something worthy of celebration!

An exhibit on the Kepler Mission along with other NASA initiatives like SOFIA, LCROSS and NLSI fascinated guests last Thursday night.  For one guest, meeting Buzz Aldrin in person was the highlight of his night.   My favorite aspect of the evening was a 3-D rendered tour of the moon and neighboring space.  I am anxious to see what will be the new annal of space exploration when April 12th and Yuri's Night comes around again in 2010.

Science Event Review— Ask a Scientist: How Computers Look at Art

 

Kishore Hari by Kishore Hari  December 4th, 2008
37.766508, -122.399282

Photo Credit: Ask A ScientistI usually write about upcoming science events, but this time I'm flipping the script.

Let me tell you about my experience at last night's Ask a Scientist: How Computers Look at Art last night (December 3rd) at the Axis Café in San Francisco. Full disclosure – I run a science café, so consider me a fan. However, I was determined to just be one of the crowd last night.

KQED QUEST has covered science cafés before, including a history of the movement. On to my story… I arrived at Axis Café about 630 PM to an almost full house (~50 people). After ordering some food and a glass of wine at the bar, I hunkered down in a cozy chair. I people watched the youngish good looking crowd for a few minutes before overhearing a conversation in front of me. A couple of women mentioned it was there first time at a science café. To both, the format sounded cool, but both they couldn't convince friends to join them. We talked for a few minutes; mainly they said most were scared off because this seemed like a science class, definitely not for the average person. No matter how you frame it, science in café still sounds like a lecture to most. What followed was hardly a lecture.

David Stork grabbed a mic and launched into a discussion on the Vermeer painting "The Girl With the Pearl Earring." His research uses computer modeling to analyze light and shadows on paintings. After skipping the math, he showed the painting nearly perfectly displayed shadows if from one light source. This confirmed what many art historians wondered, there was a model for that famous painting who sat in Vermeer's studio. The speaker was definitely moving along pretty fast, but luckily there were lots of questions to slow him down.

Professor Stork continued on, showing how this technique could also identify fakes (i.e. the cover from a Star Magazine with Brad & Angelina). Most famously, this new technique has called into question the Hockney-Falco thesis on how renaissance artists drew their subjects (using a lens of sorts).

What's amazing is that I knew nothing, nada, zip, zilch about art history and computer modeling prior to 7 PM last night. I still don't know much, but enough to talk about it with my wife and friends. That's the brilliant thing about these informal science events, the information sticks with you. It was definitely a fun way to spend a couple hours on a Wednesday night. Maybe there's a new adage out there: Science + Conversation = Fun. A glass of wine doesn't hurt that equation either.

A Swingin' History: Cal Academy's Foucault Pendulum

 

Cat by Cat  September 19th, 2008
37.7697, -122.466

Photo credit: California Academy of Sciences LibraryThere has been a lot of buzz about the innovation of the California Academy of Sciences building as of late. Yet as the opening date draws near it is the nostalgic and historical aspects of the Academy that hold my attention. There are three iconic exhibits of the Academy that have been revived – the Alligator Swamp Tank, African Hall and the Foucault Pendulum. Each exhibit has its own special history and anecdotes but I quite like the science and Academy history of the Foucault Pendulum.

The Foucault Pendulum first demonstrated in February 1851 that the Earth rotates by turning on its axis when French Philosopher Leon Foucault unveiled it in the Meridian Room of the Paris Observatory. His most famous pendulum was exhibited beneath the 279-foot dome of the Pantheon in Paris, hanging from a 219-foot wire. A replica of this famous pendulum swings in the East Pavilion of the Academy, though from only a 30 foot cable. A weight known as a "bob" on the end of a wire swings in a straight arc in relation to the laws of inertia and gravity. Below the constant back and forth arc of the bob a circle of pins set 6 degrees apart rotates. As the Earth rotates the pins come into contact with the constant arc of the bob and are knocked over.

At the Academy located in San Francisco (latitude 37.7°N), the pins will be knocked down every 39 to 40 minutes over a 24 hour period. In twenty-four hours, the pendulum will only knock over 220 degrees worth of pins. Knocking over 360 degrees worth of pins in San Francisco would take 39 hours, where at the North Pole (90° N) it would only take 24 hours.

Why is there a difference? This is because at the North & South Poles, Earth's rotation is enough to explain the change in the pendulum's apparent direction of swing. But as soon as you leave the poles and change latitude, something called the Coriolis Effect comes into play. The Coriolis Effect is an apparent deflection of moving objects when they are viewed from a rotating frame of reference, and its strength varies with latitude. Freely moving objects on the surface of the Earth experience a Coriolis force, and appear to veer to the right in the northern hemisphere, and to the left in the southern. Over time, this continual veering-off-course causes the swing of the pendulum bob to gradually precess, or rotate. This precessing is tracked as the pendulum knocks down pegs set up in a circle beneath it. The farther a pendulum is located from the pole, it will take gradually longer and longer for the pendulum's swing to precess a complete 360°. At the equator, the Coriolis effect is so weak that the pendulum is unaffected – the swing would never precess and therefore the pendulum would never knock over any pegs.

Intestingly, the Coriolis Effect also explains the spiral shapes of hurricanes, cyclonic weather systems, and oceanic gyres and which way they spiral in the northern or southern hemispheres, so the physics works for various natural phenomena, not just for pendulums.

Over two hundred Foucault Pendulums around the world were made in-house at the California Academy of Sciences. In 1958, Academy staff built a Foucault Pendulum for the Smithsonian. In 1960, Foucault Pendulums began to be produced en masses for clients around the globe. Four to five a year were produced in the instrument shop and are still being created today by a retired staff member – Cary Ponchione under "Academy Pendulum Sales". So the Foucault Pendulum on display at the Academy today is just one of many that demonstrate the axis rotation of the Earth and the specific laws of physics that affects arc, tilt and rotation.

Next Page »