Spaceflight 🚀How long would a #Mars travel currently take (with chemical propulsion, from earth orbit to landing)❓
3 month
4 month
6 month
9 month
Poll ended at .
6 months to get to #Mars 🔴.#Starship will enter Mars’ atmosphere at 7.5 kilometers per second and decelerate #aerodynamically https://www.spacex.com/humanspaceflight/mars
#NASA plans to send humans on a scientific round trip to #Mars. The trip will take about six 6️⃣ to seven months each way https://www.astronomy.com/space-exploration/nasa-wants-to-send-humans-to-mars-in-the-2030s-%E2%88%92-a-crewed-mission-could-unlock-some-of-the-red-planets-geologic-mysteries
For a trip to #Mars 🔴, decreasing travel time by 10% necessitates twice as much fuel, while cutting travel time in half requires ten times as much. May prove worthwhile when considering factors such as decreased exposure time to #radiation ☢️ for crewed 👩🚀 missions. Extra speed must be lost at Mars. Many Mars missions do this, taking about 6 6️⃣ to 7 months for transit to the Red Planet. https://marspedia.org/Hohmann_transfer#Type-I_and_Type-II_Trajectories
It is relatively easy to get 90 day trips each way with #SpaceX #Starship, because we will have a lot more fuel ⛽ to enable more direct routes to #Mars https://www.nextbigfuture.com/2024/01/spacex-starship-travel-times-to-mars.html
Earth to #Mars 🔴 transit time is roughly 180 days https://www.marssociety.org/faq/#Q15 - 6️⃣ month
Frequently Asked Questions (F.A.Q.) - The Mars Society
Q: What is Mars Direct? Q: How much will sending humans to Mars cost? Q: Why are cost estimates for a Mars mission so different? Q: Sending humans to Mars is a waste of taxpayer dollars. Q: Why should we go to Mars at all? Q: Why not just send robots? They’re cheaper and there’s no risk of death. Q: Why concentrate on Mars when there are so many problems on Earth? Q: Won’t sending humans to Mars distract NASA... READ MORE >
To get enough fuel ⛽ into #orbit for a #Mars 🔴 mission would require at least 10 launches of the #SLS rocket, or about $20 billion 💰. Just for the fuel. To use traditional propulsion, one needs to push the boundaries of #reuse ♻️ and heavy lift rockets to extreme limits—which is precisely what #SpaceX is trying to do with its fully reusable launch system https://arstechnica.com/science/2021/02/report-nasas-only-realistic-path-for-humans-on-mars-is-nuclear-propulsion
Winchell Chung ⚛🚀Yet again, journalists are confused over the difference between "fuel" and "reaction mass / propellant "
@nyrath I'm sure @sciguyspace will be delighted if you could enlighten him
Choose one:
[1] they are unaware of the difference
[2] they know the difference but are trying to simplify it for their readers
[3] article was written by an AI
But in all three cases, instructions from me would be unwelcome
But if I did, I'd refer them to my explanation:
https://www.projectrho.com/public_html/rocket/misconceptions.php#notpropellant
@nyrath you should better also inform them : "Liquid hydrogen is #NASA’s preferred rocket #fuel, and the new tank, together with the old one, will give the agency the capacity not only to accommodate the larger #fuel requirements of its new #SLS ... a lot of hydrogen is lost as it’s transferred from the rocket #fuel tank back to storage" https://spinoff.nasa.gov/NASA_Hydrogen_History_Informs_World%E2%80%99s_Hydrogen_Future
I suggest it's [2] 😁
@nyrath and those : "highly refined kerosene formulations used as rocket #fuel. Liquid-#fueled rockets that use RP-1 as #fuel are known as kerolox rockets" https://en.wikipedia.org/wiki/RP-1
Well, in the original article, the fuel was uranium 235 in the reactor, and the hydrogen was the reaction mass.
In an ion drive the fuel is the solar photons hitting the solar cell array, and the remass is the ions.
In a chemical rocket, the fuel is the lox + kerosene or hydrogen or methane or whatever, and the reaction products are the remass.
And so it goes.
@nyrath I see, but I just cited the part about "To use traditional propulsion..." (to what he was comparing the advantages of nuclear propulsion)
Yes I missed that. Point taken.
60sRefugee@spaceflight Since O2 is 80% of the fuel/reaction mass of a methane chemical rocket, has SpaceX looked at the cost and feasibility of producing lunar oxygen for its mass Mars colonization program? Not worth it for a few Mars launches but for 1000 of them?
@60sRefugee I think they currently concentrate on pure transport. But if someone offers the "mining" equipment, they could buy it and ship it there. #ISRU on #Mars would also be required. Solar energy (technology which they have themselves) might not be enough. I'm uncertain whether they would be allowed to transport a nuclear reactor.
@60sRefugee "Longer term, there is potential for operating a fusion reactor with #helium3 as a fuel" https://arstechnica.com/space/2024/03/mining-helium-3-on-the-moon-has-been-talked-about-forever-now-a-company-will-try
(Also for rocket propulsion)
@60sRefugee The Sunbird engines use #helium3. #PulsarFusion’s design is in the third phase of its development, with the ambitious aim of testing #Sunbird technology in-orbit in 📆 2027. Sunbirds shall be permanently stationed in low-Earth orbit, where they would attach to spacecraft leaving our atmosphere and propel them at unprecedented speeds toward far-off destinations, such as Mars https://www.smithsonianmag.com/smart-news/fusion-rockets-could-theoretically-cut-our-travel-time-to-mars-in-half-this-uk-startup-wants-to-give-it-a-try-180986455
Faster transit (150 days vs. 210+ with chemical propulsion), cutting total mission delta-V from ~14.5 km/s to ~9.4 km/s—a 35% reduction. This slashes launch vehicle propellant by ~50% https://pulsarfusion.com/sunbird-fusion-propulsion
@spaceflight Now, if only controlled fusion *actually works*, which absolutely no one has demonstrated yet.
@60sRefugee competition boosts innovation 🙂 “It is time to build, it is time to invest” https://edition.cnn.com/2025/02/05/climate/china-nuclear-fusion/index.html
@spaceflight nonetheless, I cannot fathom the optimism with which fusion propulsion advocates seem to think that fusion spacecraft are a turn of a screw away.
A fusion-powered #spacecraft could make the trip to #Mars 🔴 in 90 days or less.The roadmap identifies milestones in #FusionPropulsion technology to deploy fusion spacecraft in the 2030s, on par with the vast majority of fusion developers’ commercialization timelines (89% of fusion companies* anticipate fusion on the grid in the 2030s or before) https://www.fusionindustryassociation.org/fia-launches-fusion-spacecraft-propulsion-roadmap
* members : https://www.fusionindustryassociation.org/about/members
FIA Launches Fusion Spacecraft Propulsion Roadmap - Fusion Industry Association
Fusion has the potential to revolutionize space propulsion as we know it. One leg of a mission to Mars using conventional chemical propulsion can take up to nine months. In contrast, a fusion-powered spacecraft could make the trip in 90 days or less.
#NASA is considering launching rockets to #Mars 🔴 next year. #SpaceX’s #Starship is not the only contender for the trip. #BlueOrigin’s #NewGlenn is already contracted to send two small #satellites 🛰️ to Mars https://www.politico.com/news/2025/05/07/nasa-mars-rocket-launch-00331694
#US 🇺🇸 – #Italy 🇮🇹 cooperation for "two Mars Missions in 📆 2026 and 2028" https://www.whitehouse.gov/briefings-statements/2025/04/united-states-italy-joint-leaders-statement
The #Italian 🇮🇹 #SpaceAgency, ASI, has signed an agreement with #SpaceX for an uncrewed mission to #Mars 🔴 aboard one of the company’s #Starship rockets https://europeanspaceflight.com/italy-signs-agreement-with-spacex-for-starship-mars-mission
