10 Expanse Moments That Prove It’s the Best Hard Sci-Fi Ever Made

While many science fiction stories came before it, The Expanse often felt like a step forward. Though classics like Star Wars and Blade Runner are beloved, The Expanse demonstrated a stronger grasp of scientific accuracy. The series, based on the popular books by James S.A. Corey, first aired on SyFy in 2015.

Imagine a future where we’ve solved fuel problems and now live on Mars and throughout the Asteroid Belt. In this future, Mars has become a powerful, military-controlled nation, while the people and resources of the Belt are exploited. The science fiction series The Expanse takes human political struggles to a solar system-wide level, and is praised for its believable and scientifically accurate depiction of space travel and life.

The Expanse Showed the Difference in Belter Biology

As a total cinema fan, I remember when this film really blew my mind. It presented such a believable future – Earth had successfully colonized Mars and the Asteroid Belt! The story centered around a tense Cold War between Earth and Mars, both vying for control of the Belt’s resources. What really got me was the idea of people born and raised in zero gravity, living and working out there – it felt so real and thought-provoking.

People born in the Belt—known as Belters—have very different bodies than those who live on Earth or Mars, and the show made an effort to highlight this. In the first episode, a UN official, Chrisjen Avasarala, captures an OPA member who is unusually tall and thin. This elongated build is how Belters are described in the original books, but it proved challenging to accurately show this on screen.

To force the suspected Belter terrorist to talk, Avasarala exploited the difference in gravity. Belters, accustomed to living in zero gravity, were physically unprepared for Earth’s dense atmosphere. He could only survive submerged in water to counteract the pressure, and even then, Earth’s gravity caused him immense pain due to his weakened bones. This scene gave viewers a realistic glimpse into the challenges of living in the Asteroid Belt and how colonization might actually work.

The Epstein Drive Explained How Space Travel Was Possible in The Expanse

In Season 2, Episode 6, “Paradigm Shift,” which takes place 137 years before the events of The Expanse, space travel was just beginning. While Mars had already been settled by people from Earth, it wasn’t yet the dominant force in the solar system it would later become. A breakthrough in fuel efficiency unexpectedly occurred during this period, allowing for longer space voyages. This happened by chance when Solomon Epstein, a fusion engineer, was conducting experiments on his own spacecraft.

Epstein was surprised when his new engine achieved far greater fuel efficiency than he’d anticipated. This propelled him into space at an uncontrollable speed, and he was never heard from again. The immense gravitational forces prevented him from stopping the spacecraft or sending a distress signal. He was left to witness the results of his invention, ultimately succumbing to a stroke caused by the extreme pressure. Though not as spectacular as some other methods of interstellar travel, the Epstein Drive was considered one of the more plausible designs.

Space Acceleration in The Expanse Has Its Drawbacks

Science fiction stories often explain space travel in unique ways. Before the TV show The Expanse, many shows used faster-than-light drives that instantly transported ships across vast distances. The Expanse did things differently, immediately demonstrating in its first episode the physical toll such travel would take on astronauts.

In the science fiction series The Expanse, spaceships rely on powerful thrust for travel, which puts a lot of strain on the people inside. Early in the show, the crew of the Canterbury had to perform a dangerous maneuver called a “flip and burn” – quickly turning the ship around to change direction. To withstand the intense forces during this and similar maneuvers, the crew received a special injection of drugs that protected them from the effects of gravity. This medical procedure was introduced in the first episode and became a regular part of life aboard the ships throughout the entire series.

Holden Gets Creative With His Mag Boots in 0 G

Most science fiction features artificial gravity, but The Expanse takes a more believable route. The show explains that gravity in space can only be created by acceleration – meaning when characters are walking normally, the ship is actively moving. When the ship isn’t accelerating, like when it’s in standby mode, characters use magnetic boots to stay grounded.

In Season 1, Episode 4, while boarding the Donnager, Holden cleverly used his magnetic boots to help himself and Naomi survive a dangerous situation. When the ship’s engine failed during a firefight, they were left floating in space. Holden quickly secured a line to Naomi, pushed her away from him, and then activated his magnetic boots, allowing both of them to use their individual propulsion systems to quickly return to safety.

Shed’s Death Showcases the Awesome Power of Rail Guns in the Expanse

In episode 4, the battle intensified when the Donnager found itself in close combat. The Martian ship believed the Canterbury had been destroyed by the OPA, but they were surprised by an attack from six stealth ships. When torpedoes failed to do any damage, the Martians switched to using rail guns.

As a sci-fi fan, one of the coolest (and scariest!) weapons in ‘The Expanse’ has to be the railgun. It doesn’t fire bullets, but actual plasma – basically superheated, electrically charged metal shooting out in a straight line. It’s brutally effective, and we see that firsthand with poor Shed, the medic on the Canterbury. He barely lasted four episodes! A railgun blast punched right through the ship, instantly decapitating him. It was a shocking moment, and left the rest of the crew scrambling to seal the hull breach before they suffered the same fate. The whole sequence was just incredibly intense and really showed how dangerous these weapons are.

Naomi’s Reaction to Atmosphere Put a Heartbreaking Spin on Belter Physiology

From the beginning, The Expanse established that people born and raised in space—known as Belters—have bodies that function differently. Growing up in zero gravity creates problems when they visit planets with stronger gravity. While some Belters used medication to strengthen their bones and lessen these effects, it wasn’t always effective.

In Season 4, Episode 3, titled “Subduction,” Naomi Nagata finally got to visit a planet thanks to the newly discovered alien rings, which enabled travel between star systems. Many people hoping to escape life under the control of Earth and Mars wanted to settle on a new world. Holden and his crew journeyed to the planet Ilus, but Naomi found she couldn’t tolerate the atmosphere there, even after taking medication to try and help her body adjust. Despite her efforts, she continued to experience health problems.

The Tragedy of Anderson Station Highlighted the Plight of the Belters in The Expanse

Crimes against Belters are numerous and complicated, but Season 1, Episode 5, showed the human cost of these acts. Fred Johnson, once a leader in the OPA, had a dark past. Ten years earlier, he committed a terrible atrocity, slaughtering everyone – including women and children – on a peaceful station.

Belters were demonstrating against the dangerous air quality that was making their children sick. One father contacted the UN, explaining that the low oxygen levels were causing serious brain damage in his child and many others. Following a tragic accidental death, the UN ordered an execution, which Johnson carried out. This incident was just one example of the hardships faced by those living in space and the terrible conditions endured by the Belters.

Spinning the Drum Saved Drummer on the Behemoth

In space travel, the ability to accelerate quickly is crucial, as demonstrated in the first episode of the series when the Canterbury performed a risky maneuver. While the ship was strained to its limits, it was still a relatively good outcome – especially considering it was later destroyed. Even worse situations arose later, notably in Season 3, Episode 11, where the captain was in command of the ship originally known as the Nauvoo, which had been renamed the Behemoth.

When the ship entered the Slow Zone, it had to slow down incredibly quickly, causing thousands of injuries. Drummer suffered a severe spinal injury – she was crushed by a tractor – while selflessly freeing Ashford, who was also trapped. Although the ship had stopped moving, a rotating mechanism inside – called the Behemoth – generated artificial gravity. This gravity was crucial for helping Drummer and other injured passengers heal, as it restored proper blood circulation.

Avasarala’s Body Can’t Handle the Effects of High-G

Chrisjen Avasarala has primarily worked on Earth, but the escalating crisis forced her to deal with the problems in space. In the second episode of Season 3, Avasarala joined forces with a particular group. While traveling on Julie Mao’s ship, the Razorback, they discovered someone was pursuing them.

Bobby was a skilled Marine with combat experience, but he wasn’t a pilot. When he needed to perform high-G maneuvers to avoid torpedoes, it required medication just to cope with the extreme forces. Avasarala was older than most of the crew, and her body couldn’t withstand such stress without risking a stroke – a fate similar to Solomon Epstein’s. Faced with this danger, they had only one option left.

Miller and Holden Suffer the Effects of Radiation

In Season 1, Episode 10, Miller and Holden’s investigations converged as they both followed separate leads to the discovery of Julie Mao’s body on Eros. Though hesitant to work together, they were forced to team up. Unfortunately, they were then exposed to a dangerous amount of radiation. Holden accurately stated, “We’re dead,” as the situation was almost certainly fatal. Both quickly began to suffer from severe radiation sickness, a terrible illness that felt like being burned from the inside.

They eventually received treatment, but needed lifelong medication to avoid developing severe cancer and immediate death. This treatment resurfaced in Season 4 when the Rocinante crew visited Ilus. A strange alien insect began growing in the eyes of the colonists, but Holden was uniquely immune. The cancer treatment he’d undergone had eradicated anything capable of growing inside him, effectively making him the only ‘healthy’ person among those affected. The show portrays radiation effects with a level of scientific accuracy rarely seen in science fiction, and Holden experienced a massive dose.

2025-12-07 04:15