The Pacific Ocean covers almost half the surface of the Earth and despite its name can be the scene of massive storms. The entire region can be split into three regions, Micronesia and Melanesia that are on the western end of the ocean, close to Australasia, and Polynesia that occupies the central region. Polynesia is vast as can be seen by the size of the so-called Polynesian triangle consisting of Hawaii as the northern vertex, Rapa Nui (formerly called Easter Island) as the southeast vertex, and New Zealand as the southwest vertex. Each side of this triangle is about 9,000 miles. The people of Polynesia, despite being so widely dispersed, form a single, identifiable cultural group.

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Gravity is weird. It is the oldest of the four fundamental forces that we have been able to describe and yet what it is remains mysterious. When Isaac Newton first introduced his theory of gravity and the idea that objects with mass attract each other, he was accused by some critics of introducing a form of mysticism into science by postulating non-contact forces that could act instantaneously over empty space.

Einstein’s theory of general relativity brought in more sophisticated ideas by replacing instantaneous action-at-a-distance between two masses by saying that one mass distorts that space around it and that the distortion spreads through space at the speed of light and that the second mass responds accordingly when that distortion reaches it, thus removing the instantaneous action-at-a-distance problem. His Principle of Equivalence also showed that we cannot distinguish between being in a uniform gravitational field and being subjected to a constant acceleration. When we are in free fall, we are effectively weightless. The catch is that at some point, very quickly, we hit the ground.

Gravity is a ubiquitous force. We cannot shield ourselves from it. All this makes it hard for Earthbound people like us to imagine what life might be like in the absence of gravity. Now with space travel, we see astronauts in space stations in gravity-free situations. It should be noted that that he Earth’s gravitational field at the orbital height of the space station is about 90% of what we feel on Earth. But because they are in free-fall as the station orbits the Earth, they are effectively in zero-gravity (or more accurately microgravity) fields for a long time as long as they are in orbit. This has given us some idea of what life might be like in such an environment but there are still surprises. Part of the surprise is due to the fact that many forces that on Earth are small compared to the Earth’s gravitational field and are swamped by it, become significant when in zero gravity but many people do not realize this.

Take for example, a recent story about a video of Chinese astronauts (they refer to them as taikonauts) that had a glass of water. Since many people expect that in zero gravity water must float in the air in the shape of a sphere, this raised suspicions that the video had not been shot in space. But they are wrong because they ignored how important adhesive forces become in the absence of gravity.
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