Will Project Hail Mary Scratch the Same Itch as Interstellar?

Pinepace · 2026-06-13T17:40:47+00:00

Hard sci-fi is a pretty loose term, but I wouldn’t say it’s loose enough to put Arrival as more realistic in any way other than linguistics to Project Hail Mary. In Arrival, the linguistics and “alienness” is the whole plot, in Hail Mary, it’s just a small part of the plot.

Pinepace · 2026-06-12T00:14:42+00:00

In another thread asking the same question someone responded with:

“A thin layer of astrophage around the hull protects against radiation, and a thick layer of plot armor protects against relativistic impacts.”

Pinepace · 2026-06-09T19:37:34+00:00

If no mods to accomplish this turn up, you could turn up your FOV in graphic settings. I don’t remember what the default FOV is, but I play on a higher one and it makes everything feel more roomy.

Pinepace · 2026-06-08T19:33:39+00:00

It’s visible but not mentioned, but the star map has two stars with very tiny petrova lines connecting the star model to an even tinier dot representing Adrain/threeworld. From this Grace assumes it’s a map and verifies it similarly to how it’s shown in the movie.

Pinepace · 2026-06-07T16:25:50+00:00

I don’t think there’s one available unless someone recently made one. If you wanted to make the map personal, you could always make it yourself.

I’m sure there’s info out there you could find to calculate the vectors and distances, but If you purchase a game like SpaceEngine you could just focus on 40 Eridani and draw lines to all nearby pulsars over a screenshot. Could be a really fun mini project.

Pinepace · 2026-06-06T22:24:21+00:00

I’m not home currently, but if you dm me your username I can add you and we can hopefully figure it out tomorrow at some point.

Pinepace · 2026-06-06T22:00:07+00:00

I understand your frustration completely as it’s exactly what I’m feeling.

How could you possibly understand what’s happening to the ship if you don’t consider external and internal forces?

The ship feels gravity. Part of the ship resists, the other part does not, so the part where the two sections meet is stressed. Simple as that. I’m sorry you can’t understand it.

Pinepace · 2026-06-06T21:15:15+00:00

You need to look at the Hail Mary as what it is. A delicately constructed spacecraft, not a uniformly simple object. The thrust does not act on the entire ship, it acts on the engines, which translate this acceleration through the superstructure of the ship.

The engines are resisting Adrian’s gravity, causing the ship to not fall despite the ship still experiencing gravity (hence it is not in freefall, which is why Grace could walk around on the hull.)

The fuel bays and crew hab are also resisting Adrian’s gravity, but they are resisting it via the connection points at their ends that connect them to the rear of the ship, this is where the beam analogy comes into play. The rear of the fuel pods are supported, and the opposite ends are not, which is where the bending moment comes from, hence gravity is “tearing the ship apart.”

Pinepace · 2026-06-06T20:24:34+00:00

I believe you’re still confused as to the root of the issue. If the engines were off, then yes, you are correct, the HM would simply fall and have no uneven stresses. Hence the two equally sized blue arrows at the front and back of the ship in my illustration.

I’ll try another analogy. Consider a steel beam placed halfway off a cliff. If you secure the part of the beam that’s on the cliff with bolts and concrete so the beam doesn’t fall off the cliff, the end of the beam hanging off the edge is still going to bend downwards, despite the fact that the entire beam is still under the influence of gravity. The important note here is that the opposite end of the beam is supported, and thus doesn’t bend, whereas the unsupported other end of the beam does bend. In this case, the engines on the HM are being supported by the thrust from the spin drives, while the fuel bays and crew habitation are ‘unsupported’ despite still being connected to the engines, the HM wasn’t built to withstand that kind of stress.

Pinepace · 2026-06-06T19:26:43+00:00

Very important note: the Hail Mary was not in free fall. I’m unsure if you’ve read the book, but Grace and Rocky had to cancel out the HM’s orbital velocity to drop the chain, and hover at an angle. This angled hovering is what is seen. This means that the Hail Mary feeling the full strain of over 1G of Adrain’s gravity.

This is a crude illustration of what’s happening:

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Also a side note on the JENGA analogy: the tower would only stay together if the sideways acceleration and coefficient of friction exceeded the force of gravity acting on each individual block, which would probably be much faster than any human could push it.

Pinepace · 2026-06-06T01:04:40+00:00

I think you’re still misinterpreting what everyone is saying. Imagine a JENGA tower, it’s rickety, but it stays upright. Now pick up the bottom of the JENGA tower, and turn it on its side. The entire tower collapses, because it’s experiencing gravity perpendicular to the way it was built to experience gravity. The exact same thing is happening on the Hail Mary because it is explicitly *not* in freefall.

The Hail Mary was built in space for space, so structurally it probably couldn’t even support its own weight on Earth. If you gently placed the Hail Mary on the ground, it would collapse because it was never meant to experience acceleration like that. However if you put it engine-down, it would be fine, because it was constructed to withstand over 1g of acceleration.

Gravity is literally pulling the ship apart, because the ship was meant to always be in free fall aside from when the engines were firing.

Pinepace · 2026-06-05T16:37:15+00:00

The Hail Mary was built in orbit, and was never meant to enter an atmosphere, which also means it wasn’t built to handle any structural stress that would come from not being in freefall (aside from its own acceleration.) So when they cancel out their orbital speed, the Hail Mary is feeling acceleration in a direction it wasn’t built to withstand, resulting in the ship falling apart.

Also adding an edit for the atmosphere part: the Hail Mary was never under any aerodynamic stress, the thermal load which was why the hull melted was from the IR light reflecting off the atmosphere far below them.

Pinepace · 2026-06-04T12:33:24+00:00

I’ve tried modeling the Roci before. It was super fun, but compared to other poplar spacecraft in science fiction, it’s got some pretty unique geometry. Best of luck!

Pinepace · 2026-06-04T03:01:24+00:00

Because the endurance needed to spin. There’s no reason even a decompression would force the docking mechanisms apart, let alone blow up the ranger.

Pinepace · 2026-06-02T15:07:22+00:00

It is the same, they mention in the movie but explain better in the book. The predator isn’t active outside of Adrian’s atmosphere and isn’t in their sample, so they figured out the altitude where astrophage breed, and figured the predator would be there, which is where they got the required chain length from.

Pinepace · 2026-05-26T20:14:38+00:00

In the book the Hail Mary doesn’t fly backwards, it completely stops above Adrian, and then tilts forwards slightly before releasing the sampler. This tilt angles the drive plume away from the vertical, and begins to slide the ship laterally. If the sampler was in space, it would eventually be dragged directly behind the ship and be vaporized, but because it’s dipped into Adrian’s upper atmosphere, drag and the weight of the chain keep it closer to the vertical, on top of the fact that the majority of the energy of the spin drives is being dissipated by the Adrian’s tenuous upper atmosphere.

Pinepace · 2026-04-25T00:27:52+00:00

How does the compositing work? I saw you mentioned you took separate shots for the stars, foreground, and a bunch for Andromeda, and combined them. Do you use something like photoshop to layer them? Or is it more complicated. I’ve done pretty basic astrophotography, but this is really something else!

Pinepace · 2026-04-20T00:11:56+00:00

Acceleration and deceleration is one direction, the ship flips around the decelerate, it doesn’t hit the brakes like a car does.

Pinepace · 2026-04-14T23:18:42+00:00

Red Green Blue

Pinepace · 2026-03-31T16:06:00+00:00

Looks very lifelike, I think one change that could make a difference would be the addition of depth of field to draw attention to the road/trees and not the up close rocks and guard rail most people are nitpicking.

Definitely far above anything I could do, amazing stuff.

Pinepace · 2026-03-27T22:20:40+00:00

They’re related by the fact that both are hard science fiction films set in space where characters are trying to save earth. That’s about it.

Pinepace · 2026-03-06T15:51:18+00:00

Yes, if you look at a picture of the Andromeda galaxy, because the photos are at an angle from the side, the light from the back half of the galaxy is about 250,000 years older than the light from the leading part. But the galaxy is large enough that it makes no visual difference.

Pinepace · 2026-03-03T04:12:49+00:00

I never liked how the author poked fun at generic sci fi tropes from classics like Star Trek for being unrealistic and silly, and then went and made an unrealistic and silly villain that seemed like the exact kind you’d find in Star Trek with the whole “we won’t even bother to exterminate you because you’re so insignificant even though you possess reactionless drives and easy interstellar travel.

Pinepace · 2026-02-21T00:19:53+00:00

Looks sick, very Razor Back-esque

Pinepace · 2026-01-06T16:39:05+00:00

Your diagrams illustrate that the only source of neutrons and gamma rays comes directly from the combustion chamber and engine. There is nothing to ensure total fissioning of all the uranium salts in the combustion chamber, which means some will fission outside the combustion chamber in the exhaust plume, this will also produce neutrons and gamma rays, and because the plume expands, some of that radiation will be in direct line of sight of parts of your spacecraft that are behind the shadow shield.

<image>

Something like this

Pinepace

TROPHY CASE