Vast, a Startup for "human habitation, first in LEO, and then beyond"

[lamontagne]

The solar panel arrangement will go through an occultation period when they shadow one another.

How do you figure? It would spin flat to the sun.

Ah yes, could do that.  For some reason, my mind had it spinning on the minor axis rather than the logical major one.

Well, I mean it is spinning on the minor axis. The secondary and primary axis are in the plane of rotation. The minor axis points to the sun and it rotates around that.

(Unless my terminology is off.)

Je ne sais pas.  Je ne parle pas anglais.

[lamontagne]

I guess it rotates around the 'y' axis and keeps facing the sun?
In that case it has some kind of rotating Earth communication antenna?
But would have no 'overhead' and no 'deck', as it has no non-rotating element?

[JohnFornaro]

Je ne sais pas.  Je ne parle pas anglais.

Parsley... Parlè...

[lamontagne]

Interview with VAST founder.

https://payloadspace.com/vast-space-station-interview/

[Twark_Main]

Interview with VAST founder.

https://payloadspace.com/vast-space-station-interview/

New render dropped along with this interview.


Hardware evolution seems to be a straightforward iteration upon the previous design shown. So much for "reading way more into a hand-drawn sketch than is there." 


Module layout has changed from 11 modules down to 7. Each module now has 3 floors (up from two) and is roughly 100/7 = 14.3 meters tall. All modules are now the same common length. These new modules "max out" the available height of Starship's payload bay, suggesting a maximum diameter of ~5.4 meters (unless Starship gets a stretch).

Minimum number of Starship launches is therefore reduced from 11 to 7, and major module connection operations are reduced from 10 to 6. The total number of inter-module connections is also reduced from 10 to 6, decreasing the mass penalty for modularity.

PV panels indeed show the details of what looks like a cooling "circuit," which seems to reinforce my hypothesis about combining PV and radiator panels.

The center connector is definitely a docking interface. A standard NDS with its three-pedal design can clearly be seen in the middle.

There can also be little doubt now that the large squircle-shaped "door" indeed serves as the inter-module interface. On the right side of the image you can juuuuust see the bottom of the rightmost module, and it has the same type of door.


Name is the original image filename.

[Cheapchips]

Are those domed windows the same size as the ones on Inspiration 4?

[Twark_Main]

Are those domed windows the same size as the ones on Inspiration 4?

Good catch. They're the same size as the NDS shown (on Dragon the dome window replaces the NDS), so I think so!

[Twark_Main]

Scaling up the Destiny Laboratory, the estimated mass is 40-50 metric tons per module. Total station mass would be 280-350 metric tons.

Total moment of inertia about the spin axis would be 2.3-2.9e8 kg m², so at 2.99 RPM that's 7.3-9.1e7 kg m²/s of angular momentum.

If we assume a krypton thruster @4000 s mounted on the end, that's 47 kilograms of krypton for spin-up or spin-down.

To precess the station around 360° to keep the spin axis pointed at the Sun (so those nice large windows don't become nausea shadow generators) would require tau times as much, ie 292 kg of krypton propellant per year. This is feasible with current world production.

This works out to just under 10 kW of electrical power, and 292 kg of krypton costs about $50k at 65¢/liter. Both quite reasonable! 

The delta-v is 33 m/s per year. If we assume some off-axis cosine losses, we can get probably 20 m/s of reboost "for free" every year. That should suffice for any altitude above ~450 km or so.

[Paul451]

Okay, from the render only:

Seven modules. Pressure doors on each module (good). 3 pairs of arrays on each module, except the hub. (Hub unpowered until the next two SS's arrive?)


Dots are bolts not RCS. Given they don't go all the way around the modules, there would have to be another attachment going all the way around to create the air-seal, with those bolts just as reinforcement, since using just two or four points to tighten-down an o-ring is begging for twisting/gaps.

Or else the bolts are just a way to say "attachment (TBD)" (it's a render not a sketch, but it's still just an artist's impression not an engineering drawing.)


On the hub module, docking hatch at the centre of what might be a big square EVA hatch; hatch-in-a-hatch.

Don't know if there's an airlock in the hub module, or if the entire hub [/i]is the airlock. While the former makes sense (otherwise you cut off the two ends from each other during space-walks, I'm not sure you can fit a separate airlock. Project the grey frame inwards to make a rough cube and there's not a lot of room left to go around the airlock anyway, so seems logical to just make the hub also the airlock (as well as EVA service centre.) This doesn't hurt their ability to cater to zero-g customers, since the original text talked about free-flying non-rotating man-tended-but-unoccupied modules based on the same segments.

[OTOH, if that isn't an EVA hatch, then EVAs must use the hatch on the end of the baton, so despin for EVAs? It means if you extend the station, you probably want to keep the airlock module(s) on the end, which makes attaching new modules annoying. Otherwise every end module has to be designed to depress. for EVA, which is rendered worthless as soon as new module is attached. All of that would be a dumb design decision, which is why I'm favouring hatch-in-a-hatch on the hub-as-airlock.]


Render has the light at a stupid angle, so either it isn't sun-facing or they forgot to tell the artist it's sun-facing.

[There's another image (woman on a couch with her cat, watching Earth through windows) which has the paired windows sitting horizontally. So she (and the cat) are sitting on the wall. Wouldn't be the first time an artist has been given an AG concept to draw and gotten the direction of AG wrong. Expecting such an artist to understand how solar panels work is a bit too much.]


If it's sun-facing, those windows are all permanently facing the sun... Which isn't good, honestly. That's a lot of heat coming into the segments that you have to get rid of; plus a blinding view that is useless for star-gazing. (Even if you aren't looking directly at the sun, reflection off the sides of the dome frame, internal glass reflections off the multiple-layers, etc, would blow out your night vision; plus you'd be wearing sunglasses for eye safety when looking out the window.

I'd have had the windows on the permanently shadowed trailing side and a sun-shade on the sunward side. OTOH, taking the render at face value, it isn't sun-facing, so...


The weird lines and rings spraying outwards from the ends in the sketch are thankfully gone. So those obviously were just "continued however long you want" lines.

(Still no obvious radiators. But if this is meant to be sun-facing they'd be on the back.)

[meekGee]

I haven't been following closely, but something strikes me about this design:

You can't walk.

You have gravity, but you're confined to floors that are only a few meters across.

You're literally living in a medieval tower, so to speak.

You can climb up and down ladders (or stairs) but the natural activity of walking is right out.

And of course you can't float either.

Psychologically, I see this as a concern.

[JohnFornaro]

So she (and the cat) are sitting on the wall.

The weird lines and rings spraying outwards from the ends in the sketch are thankfully gone.

Aside from the fact that dogs rule and cats drool, I was able to imagine the floor she is sitting on as being a "floor" in the baton.  You do have to force your eye to see it that way; it's a bit difficult since one is seeing straight lines in the module where curved lines should be seen. Or are they saying that they've squared off the module on the inside?

Their marketing illustration of the view from inside does not agree with their view of the station from the outside.  There are no paired portal windows illustrated.  Somebody should do an animation of the view from that seat while the station is spinning.  Vertigo much?

Pix like this make their proposal less credible, imo.

[Twark_Main]

3 pairs of arrays on each module, except the hub. (Hub unpowered until the next two SS's arrive?)

More likely the hub isn't the first module to arrive.

You don't even need to wait for the "next two," just one module is needed. During such very early construction there isn't necessarily spin gravity yet.

Dots are bolts not RCS.

The phrasing of this "pronouncement" is far too overconfident. I've never seen bolted interfaces that look like that. The size, shape, and location are all wrong.


Edit to add:

OTOH, the more I think about it, the location is perfect for spin/despin and general maneuvering thrusters. They strongly prefer to be at the very end of the "rod," but ideally there's no interference when the next module is connected (to preserve maximum redundancy). This constraint means they there's really no other place to put RCS thrusters.

With multiple thrusters firing simultaneously, this could reduce inter-module bending forces. Proving out this technology might be critical if your roadmap has the company scaling to much larger structures.

On the hub module, docking hatch at the centre of what might be a big square EVA hatch; hatch-in-a-hatch.

Don't know if there's an airlock in the hub module, or if the entire hub [/i]is the airlock. While the former makes sense (otherwise you cut off the two ends from each other during space-walks, I'm not sure you can fit a separate airlock. Project the grey frame inwards to make a rough cube and there's not a lot of room left to go around the airlock anyway, so seems logical to just make the hub also the airlock (as well as EVA service centre.) This doesn't hurt their ability to cater to zero-g customers, since the original text talked about free-flying non-rotating man-tended-but-unoccupied modules based on the same segments.

I like this.

[There's another image (woman on a couch with her cat, watching Earth through windows) which has the paired windows sitting horizontally. So she (and the cat) are sitting on the wall. Wouldn't be the first time an artist has been given an AG concept to draw and gotten the direction of AG wrong. Expecting such an artist to understand how solar panels work is a bit too much.]

Where are people seeing this image? I'm not seeing this on my machine.

Render has the light at a stupid angle, so either it isn't sun-facing or they forgot to tell the artist it's sun-facing.


If it's sun-facing, those windows are all permanently facing the sun... Which isn't good, honestly. That's a lot of heat coming into the segments that you have to get rid of; plus a blinding view that is useless for star-gazing. (Even if you aren't looking directly at the sun, reflection off the sides of the dome frame, internal glass reflections off the multiple-layers, etc, would blow out your night vision; plus you'd be wearing sunglasses for eye safety when looking out the window.

I'd have had the windows on the permanently shadowed trailing side and a sun-shade on the sunward side. OTOH, taking the render at face value, it isn't sun-facing, so...

Yes, I think the main (and arguably unavoidable!) "concession" to artistry here is...  you have to see the rendering.

I suspect we're actually looking at the back (permanently shadowed) side.

The weird lines and rings spraying outwards from the ends in the sketch are thankfully gone. So those obviously were just "continued however long you want" lines.

Indeed, score another one for me. In the quoted text of the interview, the founder even explicitly calls out the expandability feature.

(Still no obvious radiators. But if this is meant to be sun-facing they'd be on the back.)

Yes, likely either we're looking at the shadow side or (less likely IMO but still possible) we're seeing tubing features "show through" from the other side of the panel.

Conformal radiators are always possible. It looks like the outer mold line is not actually the pressure vessel (see the visible window indentations).

[Twark_Main]

I haven't been following closely, but something strikes me about this design:

You can't walk.

You have gravity, but you're confined to floors that are only a few meters across.

You're literally living in a medieval tower, so to speak.

You can climb up and down ladders (or stairs) but the natural activity of walking is right out.

And of course you can't float either.

Psychologically, I see this as a concern.

These are the kind of trivial "bikeshed" objections that lead people to overlook good designs.

It's a circular room at least 18 feet in diameter. If you've ever been in a comparable size yurt you know it's surprisingly roomy. You can easily jog in a circuit within such an accommodation.

Any space station is going to be crammed with expensive equipment of course, so "jogging anywhere" is an anti-requirement,  not a requirement.

[meekGee]

I haven't been following closely, but something strikes me about this design:

You can't walk.

You have gravity, but you're confined to floors that are only a few meters across.

You're literally living in a medieval tower, so to speak.

You can climb up and down ladders (or stairs) but the natural activity of walking is right out.

And of course you can't float either.

Psychologically, I see this as a concern.

These are the kind of trivial "bikeshed" objections that lead people to overlook good designs.

It's a circular room at least 18 feet in diameter. If you've ever been in a comparable size yurt you know it's surprisingly roomy. You can easily jog in a circuit within such an accommodation.

Any space station is going to be crammed with expensive equipment of course, so "jogging anywhere" is an anti-requirement,  not a requirement.

Not overlooking it, just noting something.

In a regular space station, you can float.  I haven't tried it myself, but it looks like it makes everything roomier.  You can go in a straight line that is certainly more than 5 m long.

Here, you have gravity again, so you are confined to a floor.  5 m or so (OD, mind you, so subtract walls, insulation, wall-mounted storage or cubbies) is still pretty small.  Yes I've been in 5 m rooms.  They're certainly larger than 4 m rooms, and a bit smaller than 6 m rooms.

The idea here is to create an environment where people can do well, not just survive, and I think this is an impediment.

You could do the same things with two types of modules: long 5 m OD tubes, and shorter 8.5 m disks.

Commonality is important, but so is their goal of making a habitat that's more than just a survivable experience.

[Twark_Main]

Not overlooking it, just noting something.

In a regular space station, you can float.  I haven't tried it myself, but it looks like it makes everything roomier.  You can go in a straight line that is certainly more than 5 m long.

Here, you have gravity again, so you are confined to a floor.  5 m or so (OD, mind you, so subtract walls, insulation, wall-mounted storage or cubbies) is still pretty small.  Yes I've been in 5 m rooms.  They're certainly larger than 4 m rooms, and a bit smaller than 6 m rooms.

The idea here is to create an environment where people can do well, not just survive, and I think this is an impediment.

You could do the same things with two types of modules: long 5 m OD tubes, and shorter 8.5 m disks.

Commonality is important, but so is their goal of making a habitat that's more than just a survivable experience.

This objection is neverending.

If the modules were 8.5 meters diameter, someone would immediately complain they there are no large open expanses of parkland and forests. I've seen it happen.


This is exactly what makes people say "perfect is the enemy of good."


The only way to maintain sanity and avoid endless scope creep is to focus on real mission requirements and ignore the "wouldn't it be nice if..." treadmill.

[Twark_Main]

Let's not forget, VAST Station is clearly designed as a "minimum viable product."

The fact that it's small (while still being "big enough") is an intentional feature, not a bug.

[Paul451]

3 pairs of arrays on each module, except the hub. (Hub unpowered until the next two SS's arrive?)

More likely the hub isn't the first module to arrive.

Oh, yeah. D'oh.

Dots are bolts not RCS.

I've never seen bolted interfaces that look like that.

A bolted flange.

(If it's not, I'll say I've never seen an RCS system like that. When it was dots on the sketch, you could squint and imaging semi-hidden thrusters like on Dragon. But in the render, even that goes away.)

[There's another image (woman on a couch with her cat, watching Earth through windows)

Where are people seeing this image? I'm not seeing this on my machine.

From their website, in the "Technology" tab.

Also attached below.

I suspect we're actually looking at the back (permanently shadowed) side.

That makes the lack of radiators worse.

Conformal radiators are always possible. It looks like the outer mold line is not actually the pressure vessel (see the visible window indentations).

All modules will have MMOD protection outside the pressure-vessel-proper. Although I wouldn't have a gap around the window.

(Another absence, no MMOD covers on the windows.)

[Paul451]

So she (and the cat) are sitting on the wall.

Their marketing illustration of the view from inside does not agree with their view of the station from the outside.  There are no paired portal windows illustrated.

There are vertically paired windows. Which is why I said she's sitting on the wall. (Otherwise, where else would the artist get the idea of paired windows? And I've seen this kind of error by artists before. People walking down the spokes in a Stanford torus like they're tunnels, that sort of thing.)

Somebody should do an animation of the view from that seat while the station is spinning.  Vertigo much?

At, say, 4RPM, it's one rotation every 15 seconds. That's not a fast carousel.

Pix like this make their proposal less credible, imo.

Only for us. Good for media.

[Twark_Main]

3 pairs of arrays on each module, except the hub. (Hub unpowered until the next two SS's arrive?)

More likely the hub isn't the first module to arrive.

Oh, yeah. D'oh.

Happens to the best of us!

Dots are bolts not RCS.

I've never seen bolted interfaces that look like that.

A bolted flange.

"Bolts" are way too big.

"Bolt heads" aren't shaped like bolt heads.

Bolt spacing would be too far apart.

A bolted flange would need to go all the way around the circumference.

That's why I say I've never seen a bolted interface like that.

(If it's not, I'll say I've never seen an RCS system like that. When it was dots on the sketch, you could squint and imaging semi-hidden thrusters like on Dragon. But in the render, even that goes away.)

Many spacecraft have non-hidden RCS nozzles.

[There's another image (woman on a couch with her cat, watching Earth through windows)

Where are people seeing this image? I'm not seeing this on my machine.

From their website, in the "Technology" tab.

Also attached below.

Thank you!


Yes, clearly the geometry of this "interior shot" is not matched to the exterior.

The windows, for one, are far too closely spaced together. The distance between them is roughly 1 radius, while the exterior render shows windows with noticeably larger spacing.

The windows also seem to be flat, not "domes."

I suspect we're actually looking at the back (permanently shadowed) side.

That makes the lack of radiators worse.

Lack of conspicuous dedicated radiators, you mean.

Conformal radiators are always possible. It looks like the outer mold line is not actually the pressure vessel (see the visible window indentations).

All modules will have MMOD protection outside the pressure-vessel-proper. Although I wouldn't have a gap around the window.

Of course. Seems like a perfect structure to do "double duty" as a radiator.

(Another absence, no MMOD covers on the windows.)

Thanks, that sold me. Obviously the project is doomed, doomed!!!   

[Twark_Main]

So she (and the cat) are sitting on the wall.

Their marketing illustration of the view from inside does not agree with their view of the station from the outside.  There are no paired portal windows illustrated.

There are vertically paired windows. Which is why I said she's sitting on the wall.

That doesn't work either. The spacing is all wrong.

Somebody should do an animation of the view from that seat while the station is spinning.  Vertigo much?

At, say, 4RPM, it's one rotation every 15 seconds. That's not a fast carousel.

It's 3 RPM, so once every 20 seconds.

Be sure to get out your ray-tracer, so you can model the nauseating motion of the non-axial sunbeams across the room. 

Pix like this make their proposal less credible, imo.

Only for us. Good for media.

Only for you, methinks. The renderings don't match in either orientation.

Any interior rendering is just supposed to be "representative." That's all we should expect at this stage of R&D. No point in wasting valuable time and resources on detailed interior designs that are going to change anyway.




If it helps, we can just assume that this particular render is depicting their second-generation toroidal space station.

This seems more sensible than shoehorning the available evidence into an obviously unworkable geometric model, then blaming others for the unworkability.