UPR.F | Down, Down, Down We Go |

UPR.F | Down, Down, Down We Go

What happens when you go really deep? If you somehow ended up way down in the middle of an oceanic abyss, somewhere in the deepest parts of the ocean, you’d have a lot to worry about. It’s freezing cold, there’s a serious lack of breathable oxygen, there are weird creatures that might qualify as monsters…of course none of would matter, because you’d basically be squashed into something gooey and unpleasant to be around. The massive amount of pressure would compress your lungs far too much to work at all, along with keeping your heart from pumping.

There have been a few people who have dived to some pretty ridiculous depths, including a man named Herbert Nitsch, who dived to 830 feet in 2012. But for practical purposes, most free divers don’t go below about 400 feet, and many of them suffer ill effects for doing so–little things like bleeding in the lungs, for instance. It’s very difficult to determine what the “crush depth of a human” is because the only way to do that would be to monitor a human until, well, they died, and then going backwards from there.

Not exactly optimal.

Pressure in the Hab

Down in the Hab, we work and live at about sixty-five feet beneath the surface, which means that the outside pressure is at two and a half atmospheres above that at the surface. But wouldn’t it be better to keep the pressure even with the surface? Wouldn’t that be more comfortable?

In fact, the exact opposite is true. Having the pressure inside the Hab being equal to the water pressure surrounding us actually allows us to have an open hatch in the floor that we call a “moon pool”. Ever pushed an empty glass down into the sink, open end down?

Notice how the air stays inside? That’s because the pressure is equalized and the air stays inside as long as you push straight down.

The moon pool in the Hab works the same way – the positive pressure inside keeps the water at bay. This allows us to come and go as we need without having to flood and purge an airlock every time we want to go outside. The other advantage to this is that living at the same pressure as the outside environment – where we spend most of our time working and conducting research – means that our bodies don’t have to equalize to the pressure outside the Hab.

It does, however, mean that when we prepare to head back up to the surface after a mission that has kept us at twice the surface pressure for two to three weeks, we have to spend 18 hours decompressing!

Curriculum Reference Links

Physical World / Systems and Interactions / 3: Students should be able to investigate patterns and relationships between physical observables

10 Fun Facts: The Hab

1. Aquarius is the the world’s only permanent undersea research station.

2. Most missions last about two or three weeks.

3. Fabien Cousteau, grandson of Jacques Cousteau, beat his grandfather’s record month-long underwater expedition by spending 31 days on the Aquarius Reef Base in 2014.

4. The lab is used by NASA, the US Navy, and researchers and educators from around the globe for training and research.

5. The internet connection is better in the Hab than at many places above the water.

6. You have to swim underneath the facility in order to enter it.

7. Crew members are called aquanauts (NOT aquaNUTS!)

8. In 1994, a crew of scientists and divers had to evacuate Aquarius and climb up a rescue line to the surface in 15-foot seas after one of the habitat’s generators caught fire.

9. Aquarius was featured in the comic strip Sherman’s Lagoon in 2012.

10. The Hab was originally built in Texas.

10 Fun Facts: Coral

1. Reefs usually grow up on the east shore of land masses.

2. Parts of a coral reef can be harvested to make medications to treat cancers and other illnesses.

3. A coral reef isn’t a single organism; it’s actually a community of life that lives and thrives in one location.

4. Only about one percent of the world’s oceans contain coral reefs. That’s about the size of France.

5. Coral reefs are the largest biological structures on earth.

6. Corals are related to jellyfish and anemones.

7. There are over 2,500 species of corals. About 1,000 are the hard corals that build coral reefs.

8. Reefs grow where there are stronger wave patterns and currents to deliver food and nutrients.

9. The Great Barrier Reef is 500,000 years old.

10. Most coral reefs grow just about two centimeters per year.

10. Most coral reefs grow just about two centimeters per year.

10 Fun Facts: Invasive Species

1. To be considered invasive, a species must adapt to a new area easily. It must reproduce quickly. It must harm property, the economy, or the native plants and animals of the region.

2. Some invasive species are introduced accidentally, but others are brought deliberately.

3. Ship ballast water transports between 3,000 and 7,000 foreign species daily around the globe.

4. The total loss to the world economy as a result of invasive non-native species has been estimated at 5% of annual production

5. Invasive species have contributed to 40% of the animal extinctions that have occurred in the last 400 years.

6. Rodents are some of the worst invasive species.

7. There are an estimated 50,000 wild ring-necked parakeets in parks across London and southeast England.

8. Black and Norway rats annually consume stored grains and destroy other property valued over $19 billion.

9. Northern Pacific seastars reproduce very quickly. In one area where they were introduced, their population reached an estimated 12 million seastars in just two years.

10. Starlings were introduced to New York in the late 1800s, as part of an attempt to bring animals that were mentioned in Shakespeare‘s work to America.

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