By Jorden Demerritte
Staff Writer

An important feature of science fiction movies of all genres, such as Godzilla, Annihilation, After Earth, and Martian, is that they portray a parallel to the unanswered “what-if” questions of our society. These get gradually answered throughout the movie, for better or for worse, leaving a sickly feeling that arises upon coming too close realizing our fragility. More so, these movies offer a glimpse into an alternative reality, one where the rules of our science apply under specific and intriguing hypotheticals.

The movie Greenland follows the story of a comet (Clarke), on a dangerous trajectory towards earth, threatening planet and societal destruction. Throughout the movie, the news reporters remain the key source of information, and the protagonists and the audience receive fact-based commentary on the nature of comets.

There is much discussion in the film about whether a comet is an asteroid, and whether Clarke is a comet or not. So, what’s the difference?  

An asteroid, also known as a minor planet,  is characterized as a rocky airless remnant from the formation of the universe.

There is a more in-depth classification, which bases an asteroid’s structure on its chemical composition as well as its place of origin. A defining feature of asteroids is that they orbit the Sun, as they lack a center of gravity. 

Meteors and meteorites are an even greater puzzle, as they are coined their titles based on whether they “shine” or not. Though both are known commonly as “shooting stars,” meteoroids are generally referred to as “space rocks,” while meteors are only called this once they survive burning up in the Earth’s atmosphere and reach the ground.

NASA Science Solar System Exploration defines comets as “frozen leftovers from the formation of the solar system composed of dust, rock, and ices.” Comets can range up to tens of miles wide and heat up only once they orbit near the sun, turning into the glowing heads which we commonly know them as. They release a certain material made up of gases and dust which forms a tail that can stretch up to millions of miles.

An unnamed news reporter from Greenland expresses one of Clarke’s intriguing factors which differentiates it from typical comets.

“Unlike most comets, or even asteroids, which move much slower and are easier to track, this particular comet is not a singular body, but made up of hundreds of pieces of rock and ice that have broken up over millions of years. In fact, Clarke’s fragment trail is so long, the end stretches beyond what astronomers can actually see,” the reporter said.

According to space.com, asteroids move slower than comets, whose speed pose a dangerous issue as they have been recorded traveling three times faster than most near-earth asteroids.

The term “cosmic snowballs,” is attributed to comets based on their composition of a rocky core, and a coating of ice, dust, and dark organic matter. The ice is made up of frozen water, along with frozen substances such as ammonia, methane, and carbon monoxide. The seemingly benign difference between asteroids and comets is that comets have a tail, made up of particles of broken or evaporated pieces that surround and trail behind the nucleus. 

The news reporter of the quote above addresses a concerning aspect of the size of Clarke. The fact that Clarke’s fragment is so large that astronomers cannot see its entirety is a worrying statement which suggests that the telescopes are struggling to put it into frame. With such a size, even small fragments would cause severe damage if they were to ever hit the Earth. 

Another danger posed by comets is that they undergo a process called outgassing, which includes a combination of sublimation, evaporation, and desorption. This process is found shifting Clarke from its projected course as it starts to head towards Earth. 

In 2018, NASA discovered the first ever interstellar object to be affected by a boost in its speed and shift in trajectory. The scientists found it difficult to track the seepage of gas that was responsible for the change in the comet’s course. 

On the scale of Clarke, with fragments being described as the size of a football stadium and some fragments being quoted as “planet killers,” outgassing becomes dangerous and makes the once predictable nature of these cosmic bodies, now unpredictable and deadly.

In some ways, comets have their appeal and are treasured by those who can witness their rare occurrence. The movie Greenland, however, takes a borderline satirical view on the human condition and their reactions prior to and after receiving the troubling news that Clarke is on its way to causing  mass extinction. These reactions ranged from making a movie premiere out of a light show in the sky to brutal fear and violence brought by the desire to survive. 

There is still much to understand about comets such as Clarke. The comets in our universe hold extraordinary information that could allow us to expand our knowledge of the beginnings of the universe, our solar system, and Earth. While the movie Greenland exposes the audience to  fear of planet extinction, it fails to highlight the importance of comets and the crucial information they hold. 

Although the situation portrayed in Greenland can be considered extravagant and unrealistic, movies such as these help offer new insight on the intricacies of our universe, and address topics which remain relatively untouched in unconventional and innovative ways.