Wednesday, April 20, 2011

An Unusual Passage Through Customs

The Mobile Quarantine Facility, now on display at the
Smithsonian National Air and Space Museum.

Anyone old enough to remember July 24, 1969—the day Apollo 11 safely splashed down in the Pacific to end their lunar landing mission—can probably remember what happened next: NASA quarantined the Apollo 11 astronauts. Fearing that they might have been infected by “moon germs” and protecting against a worst-case scenario, they put the Apollo crew in their Mobile Quarantine Facility (MQF) immediately after they splashed down. Converted from an Airstream trailer, the MQF contained living and sleeping quarters, a kitchen, and a bathroom. By keeping the air pressure inside the facility lower than the pressure outside, and by filtering the air before it was vented out, quarantine was assured. They remained in it while they were flown from the aircraft carrier U.S.S. Hornet to Honolulu and then lifted by crane into another plane and flown to the Johnson Space Center in Houston where the MQF was hooked up to a larger living space, the Lunar Receiving Laboratory. Only after scientists were sure they were not infected with any contagions were they allowed to emerge, 65 hours later.
  Lesser known, though, is that on their way to Houston, customs inspectors at the Honolulu airport had a little fun with Armstrong, Aldrin and Collins. They filled out a General Declaration form for the astronauts, recording their trip from Cape Kennedy to the Moon and back to Hawaii. Under the cargo category, the form lists “MOON ROCK AND MOON DUST SAMPLES” and after “Any other condition on board which may lead to the spread of disease,” they entered “TO BE DETERMINED”(!) The form was duly signed by Commander Neil A. Armstrong, Colonel Edwin E. Aldrin Jr. and Lt. Colonel Michael Collins.
The U.S. Customs form signed by Apollo 11 astronauts Neil Armstrong, Buzz
Aldrin and Michael Collins after their return to Earth on July 24, 1969.
   Much has changed in the 42 years since that historic mission, and it’s hard to believe that we’ve not returned to the Moon in almost four decades. Richard Nixon, who famously welcomed the astronauts back to Earth from outside the Mobile Quarantine Facility onboard the U.S.S. Hornet is no longer with us, and all three astronauts are now in their 80s. For anyone interested, the Mobile Quarantine Facility is now on display at the Smithsonian National Air and Space Museum. There will be no quiz this week as a nod to spring break.
Richard Nixon welcoming the astronauts back from outside
the Mobile Quarantine Facility onboard the U.S.S. Hornet.

Monday, April 11, 2011

Flight of the Bumblebee

This week I want to dispel the myth that according to the laws of aerodynamics, bumblebees shouldn’t be able to fly. I traced the inception this rumor back to the 1934 French book on entomology, Le Vol des Incectes, by Antoine Magnan. He states in the introduction that “First prompted by what is done in aviation, I applied the laws of air resistance to insects, and I arrived at the conclusion that their flight is impossible.” Supposedly, taking the weight of a bumblebee and its wing area into account, and assuming an airspeed of a few meters per second, the wings wouldn’t produce enough lift to keep the bee up and buzzing about. 
A bumblebee in flight. The white circular arrows
indicate where the leading edge of the wings create
a vortex which produces additional lift.
  It’s true that if an airplane were built with the same proportions, it would never get off the ground, but bees aren’t like airplanes. As a bee takes flight, it creates an effect known as dynamic stall, which induces a large vortex over the leading edge of its wings. This vortex creates a low pressure region above the wing, which briefly creates several times the lift of a normal airfoil, sucking the wing up and giving the bee the additional lift it needs to buzz around. It’s just like when you stir creamer in your coffee with a teaspoon—the coffee swirls around the edge of the spoon. If you move the spoon quickly, you can actually see a depression at the center of the vortex and feel the tug caused by the lower pressure. 
  Bees beat their wings about 200 times per second. Their thorax muscles don’t expand and contract so much as vibrate, like a rubber band. A nerve impulse comes along and plucks the muscle like a guitar string. This vibrates the wing up and down a few times until the next impulse comes along. The bee has its wing roots embedded in a special block of elastic material to help this. 
  The flight of the bumblebee is quite inefficient in that its wings are not coordinated—left and right wings flap independently and sets the bumblebee apart from most other creatures of flight. Bumblebees have adopted a brute force approach to flight powered by its massive thorax. This approach could have evolved to make bumblebees more maneuverable in the air to transport nectar and pollen back to the hive.

Sunday, April 3, 2011

Easter Island

Six of the 15 Ahu Tongariki Moais, the largest 
grouping on Easter Island.

Easter Island is the southeastern most of the Polynesian Islands and the most remote. It got its name because Dutch explorers landed there on Easter Sunday, 1722. Local inhabitants of the island call it by the Polynesian name Rapa Nui. Easter Island is famous for its 887 stone monuments, called moai, which give the island a supernatural quality. These monolithic human figures are finely crafted and reminiscent of Incan stonework, yet they were carved between the years 1250 and 1500 AD which predates the Incans. Almost half are still at the main moai quarry, but hundreds were moved from there and set on stone platforms around the perimeter of the island. The moai have disproportionately large heads which represent the faces of deified ancestors. The statues faced inland overlooking their tribes, but most were toppled during conflicts between clans. The production and transportation of these statues is quite a remarkable feat, considering some reach a height of nearly 10 meters and weigh more than 75 tons.
   Anthropologists know that Easter Island was once heavily populated, yet no one is certain about what happened to these people. One recent theory is that overpopulation precipitated an ecological catastrophe which caused natural resources to become depleted. Research suggests there were millions of palm trees on Easter Island but they disappeared sometime before the arrival of European explorers. Early explorers also brought rats to the island which may have prevented the regrowth of these trees by eating the palm nut seeds. As the island was deforested, soil erosion made it difficult to sustain vegetation. A problem that continues even now.
   While ecological problems did play a large part in reducing the population from a high of 15,000 to about 3,000 inhabitants, the final blow to these people came in the form of slave trade and disease. Peruvian slave traders made several trips to the Island during the 1860s, capturing about half of the remaining inhabitants. Forced to work as laborers and servants, many died soon after they were taken from their home. Slave traders, whalers and missionaries also brought small pox and tuberculosis. By the end of the decade only 111 natives remained on the island and most of their cultural history was lost. 
Some of the more iconic rongorongo glyphs and 
what they might have meant.
   Also lost was the ability to read and write the rongorongo script, a system of glyphs discovered on Easter Island and the only Polynesian writing to have ever been found. The last few people that knew how to read and write it were among those captured and enslaved. While there have been many attempts to decipher this writing, none have been successful. How unfortunate that we cannot read one of the very few independent inventions of writing in human history and which would likely reveal many secrets of Easter Island.

1) Easter Island got its name from Portuguese explorers who discovered it in 1722.

2) The stone monuments of Easter Island, or moai, represented _____________________.
a) deified ancestors  b) Incan gods  c) Dutch explorers  d) Polynesian gods

3) True or false: Native inhabitants of Easter Island fell victim to disease, enslavement and loss of natural resources.

4) Trees could not regrow on the island because of ________.
a) harsh climate  b) disease  c) rats  d) overharvesting

5) Rongorongo is the only form of Polynesian ______________.