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This news item could also go into one of those speculative Mars transport threads
Maglev car technology tested on highway in east China
http://www.china.org.cn/china/Off_the_W … 414891.htm
A maglev vehicle technology test saw a 2.8-tonne car float 35 millimeters above the road and run on a highway in east China's Jiangsu Province.
New Vehicles run on the Changzhou-Wuxi Highway
https://www.bignewsnetwork.com/news/272 … east-china
https://www.bignewsnetwork.com/news/272 … east-china
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What to Know About Lunar Gateway, NASA’s Future Moon-Orbiting Space Station
https://gizmodo.com/nasa-lunar-gateway- … 1849194753
NASA’s intention is to reach the Moon and stay there. That will require a fully robust and functional lunar space station, so we should expect to see Gateway expand over time.
Tiny Lunar Flashlight moon probe is in trouble. NASA has one month to fix it.
https://www.space.com/nasa-moon-probe-l … -month-fix
Moon 2.38 Ve (km/s) 1.5 miles per second
Ratio (Moon/Earth) 0.213
https://nssdc.gsfc.nasa.gov/planetary/f … nfact.html
Nuclear Space Tug and VASIMR powered lunar tug also discussed in other threads
US Navy’s electromagnetic catapult launch a fighter jet
https://www.engadget.com/2017-08-01-us- … r-jet.html
Also Ion propulsion on the Smart-1 lunar probe and the Dawn mission to asteroids Ceres and Vesta.
year 2017
Old article 2008
'Navy Tests 32-Megajoule Railgun'
https://web.archive.org/web/20080325235 … le-railgun
Last edited by Mars_B4_Moon (2023-04-12 17:05:24)
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Lunar Cots ideas for Cargo, a Mars commercial trade and maybe 'Spin Launch' throwing a 10-Meter Dart Toward Space. The train track to orbit or electromagnetic railgun with potential to launch hardened payload cargo to orbit around the Moon.
Going from Mars to the Moon of Earth or Titan or Europa might use a combination launch system, skyhook, rocket sled launch, rockoon, or air launch, a portion of the total delta-v can be given as extra, either directly or indirectly, by using rocket propulsion, there might also be launch loop, or Lofstrom loop, StarTram could be possible in some future offworld colonies. Around a minor planet Asteroid perhaps in the future an Orbital ring to lift payload to orbit.
'An Inside Look: Satellite Prototyping at SpinLaunch'
https://twitter.com/spinlaunch/status/1 … 2716819830
First Launch
https://www.youtube.com/watch?v=Z6esOcWrrEE
Last edited by Mars_B4_Moon (2023-09-05 07:13:59)
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On the Moon base inside a Lava tube, a railway then goes to orbit, maybe a maglev train, but without a speed limit.
A rail to orbit from the Moon or some kind of Spin launched payload or Slingshot, Mag Launch with Electromagnetic Launch Rail Gun
CASIC achieves a breakthrough with electromagnetic launch for future rockets: 234km/h on a 380m track. A "zero-stage booster" that ups payload and frequency while cutting launch time, potentially revolutionary for commercial space!
https://twitter.com/CNSAWatcher/status/ … 7144080831
Using an Artsimovich Railgun for Return from the Moon
https://link.springer.com/article/10.31 … 4921030097
Low lunar orbit (LLO) orbits below 100 km or 62 miles altitude have a period of about 2 hours
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Watch a Japanese research ship fire an electromagnetic railgun
https://www.popsci.com/technology/railgun-ship-japan/
A railgun can accelerate a projectile to hypersonic speeds—that's more than five times the speed of sound.
an old question
Is there some fundamental limitation that would prevent steam-powered rockets from reaching space?
https://space.stackexchange.com/questio … rockets-fr
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The steam rocket built by Bob Truax to power Evel Knievel's Snake River Canyon jump attempt decades ago had an Isp around 80-85 seconds. That's no better than ordinary fireworks sold to the public. That's typical of a steam rocket based on pressurized water at 300 F and 300 psig, which starts flashing off as steam when you open the nozzle, at the rate determined by nozzle size (massflow) at that pressure.
And that low Isp is the limitation.
Truax was one of the pioneers in American rocketry. I met him decades ago, and I saw his photos and data for that steam rocket. He knew what he was doing. The jump did not need high Isp, what was needed was safety, especially with a technically-ignorant daredevil in the "driver's" seat.
Knievel's only control was the abort parachute release, a sort of deadman switch made of a cycle handlebar. Release your grip on it, and the abort chute mortar-fires out the rear of the vehicle. He let it loose at liftoff, although he swore he did not do that. The parachute deployed at launch, I've seen the movie film, in slow motion. I think he lost his grip when the launch gees (about 3) hit, and then grabbed it back immediately, but it was too late.
GW
Last edited by GW Johnson (2023-11-26 11:33:56)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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On Earth, a steam rocket may be useful propelling a rocket sled as part of a launch assist. On the moon, water is too valuable to waste in such a way.
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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Mars_B4_Moon brought the concept of a "steam" rocket back into view with Post #30.
Mars_B4_Moon does not claim to be a rocket scientist, so it is understandable that he would bring back such a concept.
For the record, the Space Shuttle was a "steam" rocket.
The Centaur rocket is a "steam" rocket ....
United Launch Alliance
The Centaur is a family of rocket propelled upper stages that has been in use since 1962. It is currently produced by U.S. launch service provider United Launch Alliance, with one main active version and one version under development.Centaur (rocket stage) - Wikipedia
Wikipedia
https://en.wikipedia.org › wiki › Centaur_(rocket_stage)
The answer to the question that Mars_B4_Moon posed is most emphatically "NO"
(th)
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The Moon, To Stay
https://www.pbs.org/video/the-moon-to-stay-lowfk8/
Season 5 Episode 4
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Just an update on this topic and why I posted the 'steam' post as ridiculous as that sounds and where I might have been coming from, I noticed in the news a few headlines again of findings of CO2 on the Moon, water readings inside the Lunar-Rock, some levels of Hydrogen and amino acids found inside Lunar Rock but not at any significant levels. In the past we had discussion of storing energy by I believe there are a few thread on 'Compressed Air'? There was also a discussion of using steam on other offworld locations, Europa and Mars and using a form of 'Steamboats' to move across the Seas and Lakes of Titanand maybe Stirling engines using closed-cycle hot air engines? There was a thread which spun off from the Titan steamboat ideas about some kind of efficient 'Steam Cycle' system. Another part of the discussion was using Rail to orbit, a type of Railway, StarTram, Maglev or Railgun that would be a very long structure maybe a bridge to the skies or inside a lava tube tunnel which would be part train but also part rocket, it was not a space elevator concept discussion although there are discussions that a space elevator might work from the Moons of Mars, it was more of a railway to orbit or a type Space fountain or 'Space gun' concept, and Rocket sled launch was discussed. Many ideas to orbit were discussed but the offworld train however was not a 'Verne Gun' also a space gun has never been successfully used to launch an object into orbit or out of Earth's gravitational pull. The Star Train or Moon-Train was also discussed as part of a wider Solar System wide economy that would transport hardened payloads to orbit, maybe the trains or trucks would also have nuclear or ion drives and help trade between worlds.
Lofstrom Loop concepts were also discussed and I believe Isaac Arthur also had videos shared on u tube social media or twitter and other bitchute and other social media platforms that discussed 'Lofstrom Loop' which would be a highly efficent way of putting payloads into orbit 'IF such a method could be made work, something traveling in a place with almost no atmosphere for example on Europa or the Moon could reach orbital velocity without having to going straight up like a rocket does on Earth, the Launch loop is a very simple idea but depending on what world you are on it might need to be thousands or hundreds of kilometers long, the Moon Iapetus a Moon of Saturn which has a diameter of 1,469 km or 912 miles already has a huge Equatorial ridge / ring sticking out and running along the equator above the surface of Iapetus. 0.0228 g of Earth or 0.138 Moon Gravity.
The train or sled to orbit was discussed as part of a hybrid rocket system on other worlds, on Earth LEO 28,000 km/h or 17,000 mph. Tahanson was part of the conversation and Calliban mentioned dry ice I believe had quoted Zubrin saying CO2 would be a more efficient readily available source with less resources and energy is wasted on Mars. Low orbits on the Moon or LLO below 100 km (62 mi) altitude are very unstable but the train to space was discussed as part of a hybrid mission fusing ideas for offworld transportation. The Moon's gravity map is very uneven and Lunar probes had difficulty in the past due to lumpy gravity, however we do know Chang'e was able to get as low as 15 km (9.3 mi) in a stable but very elliptical orbit. The Moon of Saturn Titan has gravity comparable to Earth’s Moon, the Moon of Jupiter Europa's gravity is approximately 13% of Earth's, the escape velocity of Earth's Moon is about 2.4 km (1.5 miles) per second, Titan has a significant atmosphere so any attempt to put a train-rocket type craft into orbit will have aerodynamics and drag, water is rare on the Moon while Europa and Titan however have lots of water.
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The performance of a steam rocket depends upon what you consider to be a "steam rocket". If you flash off pressurized hot water into steam at lower pressure, the inherent Isp will be low, because values of pressure and temperature for the source, hot water under pressure) is quite technologically limited.
Chemical rockets using liquid oxygen and liquid hydrogen produce steam (water) as their combustion product, that is true. They have quite high performance, because the source is chemical combustion, not simple internal energy. I did not consider them to be "steam rockets", because of the combustion energy source. More of a semantic definitional thing. I see oxygen-hydrogen as a combustion thing, same as oxygen-kerosene, etc.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Catapults can fail so then is it worth the risk of tossing a Rocket or Unmanned Spaceplane? How feasible is it to throw an Apollo or Soyuz sized capsule or Shenzhou or unmanned mini-Shuttle out from your Lunar town before it takes off into space? the only part going on the final journaye to Earth or Mars from the Moon would be the reentry module
In past discussions we had 'radical' ideas of circular accelerator concept or 'Spin Launch'
On Earth when a whip is cracked, the tip of the whip moves faster than the speed of sound, it would take a special catapult whip to toss any payload, one the Moon on of the lower orbits was from the Lunar Reconnaissance Orbiter at 12 miles (20 km). Seen in Ancient Weaponry, old Siege Warfare weapons and the Physics of Throwing Payload, they were a fearsome middle age weapon that would toss a boulder maybe covered in burning oil at a Castle. There will be no ancient battles on the Moon but maybe the idea of throwing a payload could be reused, they would probably be inside a Cave or Lavatube structure to shield the ballistic 'Catapult' from the Moon's long day and long night. The Payload would be a hardened structure and maybe have its own propulsion a rocket to boost it more or an ion drive for example.
video of people who reenact and do historical engineering feats
'Unleashing a Medieval Trebuchet on a Wooden Palisade'
https://www.youtube.com/watch?v=cs8gamnMIS0
Even discussion of a Whip Launch or Trebuchet design
https://space.stackexchange.com/questio … des-rail-g
the user 'Woody' Last heard saying. "Whoa. Lost my eyebrows again." seems to have an enthusiasm for engineering and astronomy
Apollo’s Low Lunar Orbit was about 1600 m/sec, about 4.6 times the speed of sound at STP. It would likely be a trivial problem to achieve similar speed with a whip in a vacuum if it had no “payload” on the tip. If there is any payload added to the tip, the transferred momentum would need to be divided between the mass of the whip and the mass of the payload. In other words, high mass whip and small mass payload is needed.
To put some numbers to the model, assume we can borrow the aircraft launch catapult from the carrier USS America. It can accelerate 36,000kg to 72m/sec.
Assume our whip, as loaded with an 800kg payload, weighs 36,000kg and is accelerated to 72m/sec. In our frictionless vacuum world, half the momentum is transferred to the payload as per the roller chain model. That would give a payload launch speed of 1600m/sec … good enough for a low lunar orbit.
There is a big difference from 72m/sec to 1600 m/sec
'Supersonic Projectile Exceeds Engineers Dreams: The Supersonic Trebuchet'
https://hackaday.com/2021/12/01/superso … trebuchet/
in excess of 450 meters per second!
a discussion from 10 years ago
https://physics.stackexchange.com/quest … -trebuchet
'Catapult vs. Trebuchet'
Burns for EML-1 to LLO
https://space.stackexchange.com/questio … l-1-to-llo
On-orbit depot architectures using contingency propellant
https://www.sciencedirect.com/science/a … 6513004268
Launch and deployment of distributed small satellite systems
https://www.sciencedirect.com/science/a … 651500171X
Each colony or town might use whatever system is suitable, maybe even an idea as ridiculous as a Catapult tossing a rocket is considered? if the payload is not thrown or flung correctly any course corrections requires delta V
Lunar Electromagnetic PDF NASA
https://ntrs.nasa.gov/api/citations/201 … 007073.pdf
'A Lunar Electromagnetic Launch System for In-Situ Resource Utilization'
'Design and analysis of a direct transfer trajectory from a near rectilinear halo orbit to a low lunar orbit'
https://www.sciencedirect.com/science/a … 7720307857
Trajectory Design Considerations for Lunar Surface to Near Rectilinear Halo Orbit Rendezvous
https://ntrs.nasa.gov/citations/20220018387
Options for Staging Orbits in Cis-Lunar Space
https://ntrs.nasa.gov/citations/20150019648
NASA Lunar Gateway will be a highly-elliptical seven-day near-rectilinear halo orbit around the Moon, which would bring the small space station within 3,000 kilometers (1,900 mi) of the lunar north pole at closest approach and as far away as 70,000 kilometers (43,000 mi) over the lunar south pole
However even on Mars, NASA has considered Tossing its Mars Sample Return into the sky, throwing it before the rocket launches on a return journey to Earth.
Throwing a payload before the spacecraft truly starts flying also might save fuels and save risk to the local habitat and colonists who live near the Launch site?
Last edited by Mars_B4_Moon (2023-12-12 10:13:44)
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DARPA Is Considering Putting Trains on the Moon, Needs Someone to Build It a Railway First
https://www.autoevolution.com/news/darp … 31123.html
'China Wants To Fire Astronauts Into Space Using An Electromagnetic Railgun'
https://www.iflscience.com/china-wants- … lgun-73480
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