Goofs

The position of Rook and his arms and hands changes multiple times.

78 min. Andy says that 25% of the human genome is shared with rats. In reality about about 85% of human genome is shared with rats.

(at around 22 mins) When the characters first enter the space station, the artificial gravity briefly turns on and then off again. Shortly thereafter, they enter a room where several objects are hovering in mid-air. If the objects had momentum immediately after the gravity switched off they should be moving on a trajectory, and if not they should still be against the floor. Either way, they should not be unmoving several feet off the floor.

(at around 57 mins) When Rain, Andy and Tyler had to go through the room filled with face-huggers, the temperature was raised to body temp, as temperature is one of the ways face-huggers track people, in addition to movement. As soon as the doors were opened, the room temperature would have immediately started dropping, making the effort meaningless.

(min 22) The characters are crawling though a vent with great difficulty, after boarding the station. They see a dead rat floating in the air revealing a lack of gravity in the station. The fact that all three characters are dragging themselves across the floor of the vent while in zero gravity is contrary. They should be floating through the vent.

The planetary ring is on one occasion called an asteroid belt. The two are utterly different.

The mining colony is on a planet with Saturn-like rings on it. But these can only form in a stable way on planets whose gravity is far far greater than Earth. If most of the mining operation is extremely deep underground, this might still work, but it would be unfeasible if the mines were near the surface of the planet.

Correction: While planetary rings most commonly exist around gas giants they can and do exist around smaller rocky planets. The New Horizons probe revealed several dwarf planets in our own solar system have rings including Chariklo, Chiron, Haumea and Quaoar. Additionally evidence has been found indicating Earth may of had a ring system for at least 40 million years during the Ordovician period about 466 million years ago which originated from a large meteor cluster that passed near Earth getting caught in Earth's gravity well; evidence for this ring comes from impact craters from the Ordovician period appearing to cluster in a distinctive band around the Earth's equator.

(at around 1h 28 mins) In zero gravity, liquids form up into blobs and spheres due to surface tension. When Rain shoots the Xenomorphs in zero gravity, their blood stays stretched out and acts unrealistically.

Correction: This would be true of most Newtonian fluids, but as Rook stated he found that the Xenomorph blood contained non-Newtonian fluids, the blood's behavior is very realistic for a non-Newtonian fluid in zero gravity; in fact human blood is also non-Newtonian. Which are fluids that do not follow Newton's laws of viscosity, instead having a variable viscosity dependent on stress and force; in other words they become more fluid when in motion and more solid when sitting still, especially when compacted, ketchup being a good example. Non-Newtonian fluids behave strangely in zero gravity, since their viscosity isn't constant, surface tension causes them to behave differently, displaying viscosity changes due to sheer pressure even more prominently. Meaning instead of forming into spherical blobs it would become more fluid when gently disturbed but quickly solidify when impacted, like being hit by a bullet. Explaining why the Xenomorph's blood became very compacted together when they were initially shot but quickly spread out becoming extremely fluid as the centrifugal force of the station rotating gently acted on the blood, which is why it began to spread out in spiral shapes, reflecting the motion of the station. Although if the blood was allowed to loose its momentum and the station became stationary and ceased rotating then its surface tension would cause it to form into spheres, but only when no longer acted on by an external force.

Andy only raises the room to human body temperature to prevent the facehuggers from detecting their body heat. He should have raised it to much higher than body temperature to actually mask their heat signatures.

Correction: Thermal vision doesn't work simply by just detecting heat, it specifically works by detecting temperature differences between objects, a really warm object stands out if the ambient temperature of the surrounding environment is much cooler. Likewise a cooler object would standout if the surrounding environment was much warmer. So if Andy had raised the temperature of the hallway to a level much higher than human body temperature that wouldn't help them blend in, they would be just as visible as when the hallway was really cold, especially when moving. Making the ambient temperature of the hallway the same as average body temperature is the best way to go undetected by thermal vision.

Andy is only one that is in no danger from the face-huggers. He should be going in there first by himself and grabbing them by their tails and shoving them into boxes or some other container to neutralize their threat.

Facehuggers are not defenseless animals. The one that attacked Kane in Alien (1979) spat acid onto his helmet and it took 3 grown adults to keep one from choking Ripley in Aliens (1986)

When Rain shuts off the station's gravity (before shooting the Xenomorphs), objects laying on the ground, as well as the creatures, begin to leap upward. Per Newton's law of gravity, "an object at rest stays at rest".

Correction: This would be true if the space station were in a stable orbit and not moving, however its orbit is decaying rapidly due to the fuel tank rupture, making the station both free-falling and moving towards the planet from inertia. This would cause any objects inside the station to lift off the ground when the gravity fails due to their inertial movement being different from the station's, they would continue "floating" up until hitting the ceiling or acted on by another force.

(at around 2 mins) At the start of the film, a probe finds parts of the wreckage of the Nostromo floating in space near Zeta² Reticuli following its destruction a couple of decades earlier at the end of Alien (1979). Despite it being dubious there would be any wreckage left after what was such a monumental explosion, any parts of the ship that were not vaporised would not be simply floating in space around the area the explosion happened decades later. The force of the Nostromo's self destruct would have projected remnants of it in all directions at considerable speed, and since this is the vacuum of space, the remnants wouldn't slow down, they would simply keep flying through space at speed.

When Rain shoots the Aliens in the corridor why do the now dead alien bodies disappear? Only their blood remains in zero gravity but their bodies should be there too.

The various newborn aliens increase in mass dramatically in a short period of time, with no apparent source of nutrition or plausible biological explanation. The incubation has never been a matter of minutes or seconds, but over a period of hours at the fastest.

This is simply how the Xenomorphs and their other related aliens function. Part of why they are considered "perfect organisms" is because they require very little sustenance and reach adulthood incredibly fast. But as with some of the other films, the incubation and growth times has never been consistent and almost always changes to suit the plot.

Just after Tyler and Rain have rescued Kay from the cocoon, Andy notices the layer of luminous blue mist on the floor. This is the same mist from the derelict Engineers ship from the first film, that was covering the eggs in the ship's hold and reacts when broken. Unless the Company scientists had been back to the derelict ship in the intervening years (which they obviously haven't), there is no explanation as to how and why is it now here.

The rings of the planet appear to be made of ice rather than rock. As with any space-faring vessel, the Renaissance station would be designed to withstand impacts from micro-meteors and other relatively small space debris. Chunks of frozen water should not be enough to damage it's hull, but the station gets ripped apart when it begins to collide with the rings.

Equipment Visible at 1:43:50-54 - Rain is seen running barefoot on metal grid-mesh/grated flooring, adhesive medical tape can be seen strapped to the bottom of her feet to prevent injury from the flooring.

In the opening and end scene, when space and stars are shown, the stars are twinkling. This is incorrect. It is the oxygen of the earth that causes that effect, one of the reasons that scientists want telescopes in outer space--nothing to distort the image.

(at around 45 mins) Rook has no way of knowing there was a sole survivor from the Nostromo or that Ripley had blown the Alien out the shuttle's airlock. Ripley's log at the end of the first movie never mentions blowing it out the airlock, or that it was ever even in the shuttle with her. But additionally this wasn't a transmission that Ripley made, only a log. If it was a transmission then why wouldn't she wake herself up in 6 weeks when she reached the frontier to broadcast more reports to get picked up sooner instead of floating in space for 50+ years.

No explanation is given as to how the company scientists on Romulus reverse-engineered the alien to make facehuggers (and seemingly without eggs too). Not even the far more advanced scientists over 200 years into the future in Alien: Resurrection (1997) could do that, they had to clone Ripley in order to get the queen alien embryo from her and enable it to produce eggs in order to produce facehuggers and subsequently full-size aliens. This suggests there is a queen somewhere on the station, but if there is she isn't shown or mentioned.

Since this movie takes place between Alien (1979) and Aliens (1986) and it is shown that the Weyland-Yutani Corporation already did some extensive research on the Xenomorphs, they had no reason to send Ripley to LV-426 in Aliens, because by that point they already knew what they would find and most likely knew more about the species than Ripley did.

When the Corbalen switched from auto pilot to manual, it suddenly coasts to a stop when in reality, in space, there would be no gravity or atmosphere to stop it. The Corbalen should therefore have continued moving until someone manually braked her.

Andy is Weyland/Yutani proprietary tech, how is Rain allowed to have that on a W/Y mining world? They would definitely want that back. To decommission, or have destroyed at the very least if it is obsolete. There is no way they would allow some skid row teen go around using it to access their systems. Much less a top super secret alien research station.

Around 22 minutes, while in space, the ship would have an all oxygen environment, yet one of the crew members is smoking a cigarette. If it was an all oxygen environment the ship would be engulfed in flames.

(at around 6 mins) In the opening there is a reference to the population of the mining town of under 3000; yet In the streets shopping there were around 3000.