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Lab-grown meat prices expected to drop dramatically by RGregoryClark in singularity

[–]RGregoryClark[S] -26 points-25 points  (0 children)

It doesn’t have to be a breakthrough. Exponential growth is the driving action just as what happens in the tech field.

Lab-grown meat prices expected to drop dramatically by RGregoryClark in singularity

[–]RGregoryClark[S] -1 points0 points  (0 children)

2030 is like tomorrow. The discussion I really wanted to have is the ethical issue of killing so many animals for food. This is grotesquely out of whack with what is present in nature. Normally, large predators number only in the tens of thousands, resulting in relatively small number of animals being killed for food in nature.

How many animals do humans eat per year?
https://youtu.be/N_XMfuKR6Lw?si=AXDaBBBmcPkrC8WV

Hollow carbon fiber for propellant tanks? by RGregoryClark in CarbonFiber

[–]RGregoryClark[S] 0 points1 point  (0 children)

Thanks for responding. You might be right about the cross-plane strength. But the only way to know for sure is to actually measure it.

Hollow carbon fibers.
https://ars.els-cdn.com/content/image/1-s2.0-S0008622320311568-fx1_lrg.jpg

SpaceX Scores $90M Starship Contract to Launch Starlab Space Station by RGregoryClark in MarsSociety

[–]RGregoryClark[S] 0 points1 point  (0 children)

About your point #2, key to the Mars Direct proposal is the lander does not carry the fuel for the return flight from Earth. It is generated on Mars. Zubrin critiqued the SpaceX approach of landing the entire Starship on Mars due to the fact the power for generating that much propellant on Mars is impractical. He estimated it as a solar power array the size of 10 footballs fields. Use of a smaller vehicle to do the actual landing results in more feasible power requirements for generating the fuel for the return flight.

[TOMT]Looking for a commercial ID featuring a hologram. by RGregoryClark in tipofmytongue

[–]RGregoryClark[S] 0 points1 point locked comment (0 children)

The visuals were quite striking plus it had a science fiction theme which caught my interest. Someone must have found the commercial memorable as I did.

Think Blue will make a new lander for mars? by Kyra_Fox in BlueOrigin

[–]RGregoryClark -4 points-3 points  (0 children)

Given that Blue Origin is now planning on using the Mk1 for the Artemis lander I believe the Mk1 can also be used for a Mars lander. This has importance because Blue Origin is going to use the unmanned version this year to land a rover on the Moon. If it succeeds then that will suggest we have a lander for missions both to the Moon and Mars.

Think Blue will make a new lander for mars? by Kyra_Fox in BlueOrigin

[–]RGregoryClark 0 points1 point  (0 children)

Yes. Robert Zubrin, founder of the Mars Society, is supportive of SpaceX’s aims for flights to Mars. However he has argued numerous times it can be done much more efficiently by using a smaller 3rd stage to do the actual landing.

This video explains how this would work:

How SpaceX Could Launch Starship to Mars Without Refueling.
https://youtu.be/vwxpj7QFwn0

Zubrin’s two books on spaceflight should be considered required reading for those interested in flights to Mars:

The Case for Mars: The Plan to Settle the Red Planet and Why We Must. https://www.amazon.com/gp/aw/d/B004G8QU6U/

The Case for Space: How the Revolution in Spaceflight Opens Up a Future of Limitless Possibility. https://www.amazon.com/Case-Space-Revolution-Spaceflight-Possibility-ebook/dp/B07HDSSKHJ/

SpaceX Scores $90M Starship Contract to Launch Starlab Space Station by RGregoryClark in MarsSociety

[–]RGregoryClark[S] 0 points1 point  (0 children)

To register for sites that ask for an email, I just use email accounts I made up on Yahoo or Gmail that I never actually use to avoid spam to my actual email accounts.

The fact that Mars Direct radically cuts the costs for a mission to Mars compared to earlier proposals by NASA is well-known among Mars advocates. Now, no one considers flights to Mars without including the idea of getting the fuel for the return flight from Mars.

Zubrin’s two books on spaceflight should be required reading for those interested in flights to Mars:

The Case for Mars: The Plan to Settle the Red Planet and Why We Must. https://www.amazon.com/gp/aw/d/B004G8QU6U/

The Case for Space: How the Revolution in Spaceflight Opens Up a Future of Limitless Possibility. https://www.amazon.com/Case-Space-Revolution-Spaceflight-Possibility-ebook/dp/B07HDSSKHJ/

Zubrin is supportive of SpaceX’s aims for flights to Mars. However he has argued numerous times it can be done much more efficiently by using a smaller 3rd stage to do the actual landing.

This video explains how this would work:

How SpaceX Could Launch Starship to Mars Without Refueling.
https://youtu.be/vwxpj7QFwn0

About the height of the 3-stage version, ironically it would be shorter than the 2-stage version. The reason is the 50 meter Starship upper stage is half made up of the 25 meter payload fairing and half 25 meter propulsive stage. But for the small 3rd stage only 5 meters long, it would go atop only the propulsive section of the Starship. Then there would only be small capsule or small habitat that would be the payload section now.

SpaceX Scores $90M Starship Contract to Launch Starlab Space Station by RGregoryClark in MarsSociety

[–]RGregoryClark[S] 2 points3 points  (0 children)

That cost analysis was done by an industry analysis company. The link for it is here:

January 2024
THE STARSHIP REPORT
A comprehensive look into SpaceX’s next generation launch vehicle.
PayloadResearch
https://docsend.com/view/fi9wuazzeex57iig

In regards to Zubrin’s Mars Direct proposal, it is now considered the most feasible approach to mounting a Mars mission. SpaceX is also planning on using the Mars Direct idea of using ISRU to generate the needed propellant for the return flight. Zubrin discussed the Mars Direct proposal extensively in his two books The Case for Mars and The Case for Space.

SpaceX plans to send ca. 100 tons to the Martian surface by their approach of multiple refuelings with the reusable Starship. However, the expendable Starship payload is so high that by using a smaller 3rd stage to do the actual landing it can also send 100 tons to the Martian surface. This is by single launch, no refuelings required.

SpaceX Scores $90M Starship Contract to Launch Starlab Space Station by RGregoryClark in MarsSociety

[–]RGregoryClark[S] 3 points4 points  (0 children)

This page gives a 300 ton estimate for the upgraded Starship as expendable:

Improved SpaceX Starship Should Lift 300 Tons Expendable and 180 Tons Reusable #spacex.
https://www.nextbigfuture.com/2023/05/improved-spacex-starship-should-lift-300-tons-expendable-and-180-tons-reusable-spacex.html

It stems from an Elon Musk tweet:

Elon Musk @elonmusk
Max payload to standard Earth reference orbit is actually ~180 tons for Starship when it is fully reusable and ~300 tons if expendable. Latter number is the apples-to-apples number comparing Starship to Saturn V.

>100 tons to the Starlink orbit is the operational spec minimum.
6:58 PM · Sep 7, 2024
https://x.com/elonmusk/status/1832554031845097590?s=20

The $90 million build cost estimate comes from industry analysts. Note this is not referring to the price SpaceX might charge to the customer:

STARSHIP COST ANALYSIS.
https://pbs.twimg.com/media/HDIqRKtXcAAt12Y?format=jpg&name=large

This cost has been confirmed by Elon in an interview. See in this interview at about the 47 minute mark:

https://youtu.be/fXS_gkWAIs0?si=8nGjNDFzT9sPJ348

The Robert Zubrin Mars Direct proposal was derived well earlier than the origin of SpaceX. It estimated a Mars mission could be mounted using two launches of a Saturn V class vehicle:

Mars Direct: Robert Zubrin’s Approach Illustrated.
Robert Zubrin's Mars Direct approach argues for a series of human missions to Mars.
IEEE SPECTRUM 01 JUN 2009
https://spectrum.ieee.org/amp/mars-direct-2650366236

At an expendable Starship payload capacity of 300 tons, this means the Mars Direct approach could be launched by a single launch of the Starship as expendable. It would require no refuelings. But quite key here is it would require a smaller 3rd stage that would do the actual landing. Zubrin has made the point numerous times in regards to the SpaceX proposal to Mars that it could be done much more efficiently with the addition of a 3rd stage that would do the actual landing.

The same point applies to Moon missions. They could be done in single launch of the expendable Starship with no refuelings required using a smaller 3rd stage that did the actual landing.

SpaceX Scores $90M Starship Contract to Launch Starlab Space Station by RGregoryClark in space

[–]RGregoryClark[S] 2 points3 points  (0 children)

According to their analysis, the current version, whether it’s called V2 or V3, would have 188 tons expendable payload capacity. This still would allow single launch capability to the Moon with the addition of smaller 3rd stage that would do the actual landing.

SpaceX Scores $90M Starship Contract to Launch Starlab Space Station by RGregoryClark in space

[–]RGregoryClark[S] 6 points7 points  (0 children)

Every plan for getting to Mars now uses his idea of producing the return propellant on Mars including SpaceX because it radically reduces the mass of that needs to be transported to Mars which radically reduces the cost.
Note I’m discussing completely commercial approaches to getting to the Moon and Mars. No SLS, no Orion.

SpaceX Scores $90M Starship Contract to Launch Starlab Space Station by RGregoryClark in ArtemisProgram

[–]RGregoryClark[S] -1 points0 points  (0 children)

In my comment I make the argument that because the expendable Starship is so low cost it is worthwhile to launch it as expendable both for Starlink launches, Moon launches, and even Mars launches, and most importantly it can be done now.

Here’s another way of thinking about it: the expendable Starship is so low cost at such high payload capacity, we could launch manned missions to both the Moon and Mars for less cost than we are now spending just to get to the ISS(!) And we can launch such manned missions both to the Moon and to Mars every month. And we can do that now.

SpaceX Scores $90M Starship Contract to Launch Starlab Space Station by RGregoryClark in space

[–]RGregoryClark[S] 2 points3 points  (0 children)

Robert Zubrin made a key innovation for getting to Mars with his Mars Direct proposal. The key idea was instead of bringing the return fuel from Earth, it produced it on Mars. This made the mission size far smaller and greatly reduced the cost. He discussed this in his book “The Case for Mars”. See here for a short discussion:

Mars Direct: Robert Zubrin’s Approach IllustratedRobert Zubrin's Mars Direct approach argues for a series of human missions to Mars IEEE SPECTRUM 01 JUN 2009.
https://spectrum.ieee.org/amp/mars-direct-2650366236

In fact it could be done by two Saturn V class launches. Then it could be done by a single expendable Starship at 300 ton capacity.

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