Physics in Cinema: Avatar
Released in 2009, the movie Avatar was an overproduction that marked the cinema with its visual effects, 3D technology and nine nominations at the 2010 Oscar. The story takes place in 2154 on Pandora, the moon of a fictional planet. A soldier is sent to infiltrate and help in the colonization of Pandora, where human colonizers and natives, called Na’vi, wage war for the planet’s resources.
Because the film takes place in a different world, many laws of physics applied on Earth would have no value. Although, it is still possible to analyze some aspects based on the characteristics that history shows about Pandora.
Pandora’s gravity is 80% that of Earth, the atmospheric density is 20% higher and the pressure at sea level is 10% lower. In addition, Pandora’s atmosphere is composed of nitrogen and oxygen, but there is also ammonia, methane, hydrogen cyanide, with 18% carbon dioxide and 5.5% xenon. That is, it is a toxic atmosphere for humans and therefore it is necessary that they protect themselves with exomasks.
Pandora’s low gravity can lead to positive or negative changes. For example, birds make less effort on their flights compared to the Earth’s atmosphere. In addition, this would be one of the main explanations for the considerably higher stature of the Na’vi, since the force that pushes a body against the planet is smaller, resulting in a larger growth. An adult Na’vi can reach up, on average, to three meters in height.
Aleluia Mountains and the Unobtanium
In Pandora there are the Aleluia Mountains, rock formations that float. A physical explanation for such a phenomenon would be the fact that they are located between the magnetic poles where the field lines would be stronger, in an area called “vortex flow”. These rock formations are formed by the fictitious ore called unobtanium, mineral abundant in Pandora, whose atypical magnetic and superconducting properties cause levitation. Thus, the so-called Meissner Effect occurs which says that a superconductor below critical temperature would acquire diamagnetic properties causing the fields to repulse and, consequently, levitate the islands.
In the film, the most amazing fact about unobtainium is that its superconductivity occurs at ambient temperature, which levitates Alleluia Mountains naturally. On Earth the phenomenon of superconductivity at high temperatures (about 196 ° C) has not yet been explored. Until then only in low temperatures was obtained superconducting materials. The current record of superconductivity was at -135 ° C, with a compound made up of mercury, thallium, barium, calcium, copper and oxygen.
Did you like to understand a little more about the physical phenomena that happen in the movie Avatar? Check out our physics in cinema session and read more about other movies.