By Jo Nova
Ponder the remarkable physics
SpaceX just launched Starship Flight Test 7. As Elon Musk says about the booster section: “Atmospheric reentry speed is more than twice as fast as a bullet from an assault rifle and this is the largest flying object ever made“. Yet they still manage a perfect catch. The top speed on the return of the booster was 4,135 km/h. It went to space and back in just 7 minutes, reaching 90 km up.
The unmanned test rocket though, wasn’t so lucky, as SpaceX described it, suffering a ‘rapid unscheduled disassembly during its ascent’.
The launch itself is a spectacle of raw power. As the rocket lifts off, it is so powerful it appears to create the weather around it almost, tearing through the atmosphere. Elon explains: “You can see the much higher propellant mass fraction of the new ship design by the percentage of rocket that is frosty.”
One commenter said SpaceX will change the way we fly. Elon said “Yes”.
Imagine being able to fly anywhere in the world in under an hour…
SpaceX Earth to Earth Transport will enable:
LOS ANGELES TO NEW YORK
5 hours, 25 min —> 25 minBANGKOK TO DUBAI
6 hours, 25 min —> 27 minTOKYO TO SINGAPORE
7 hours, 10 min —> 28 minLONDON TO NEW YORK
7 hours, 55 min —> 29 minNEW YORK TO PARIS
7 hours, 20 min —> 30 min… pic.twitter.com/Q9YsOahnOl— Nic Cruz Patane (@niccruzpatane) January 17, 2025
It’s a strange moment in history. So much corruption and graft, yet also something extraordinary…
Flight time might be under an hour but the whole journey, door to door will take much longer!
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Yes much like the “one hour flight” to Sydney for us. Once you add it all up we may as well drive our non EV , and have our own car when we get there.
Dont really see the connection between there SpaceX flights and commercial aviation.Maybe I just lack the vision thing.
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The vision thing is another issue.
I think it is unlikely that the rocket will have any windows, so no looking out at the wonderful view!
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It’s a shame Musk wasn’t in charge at Reaction Engines. Their Sabre hybrid gas turbine/rocket engine and Skylon space plane had the potential to be a real game changer. Skylon was designed for conventional take off to orbit and runway landing. There was an estimated 48 hours turn round time to get it back in the air. The LAPCAT, using the Scimitar engine, was designed as a Mach 5 passenger plane. Granted, LAPCAT would not have been as fast as the Musk option in the story above, but London to Sydney in 4 hours at an projected cost similar to a current first class airfare. I can’t help but think that if Musk had been in charge, these things would have been up and flying by now. Hopefully someone with enough cash and vision will pick up the remnants.
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Maybe for hypersonic missiles but liquid oxygen is cheap. Get out of atmosphere ASAP by going vertical as shown by Falcon 9 and Superheavy booster. Saves lots of nasty aerodynamic and heating issues. The first stages are the tugboats taking the ships out of harbour.
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There is a push to build a bullet train in Texas from Dallas to Houston.
It sounds so convenient but travellers will still have to get to the depot, check bags, pass security before entraining and retrieve baggage and arrange transportation at the destination. Other than for downtown to downtown walking distance business,it would likely be no quicker than flying.
BTW How’s that $ multibillion kalifornika high speed rail from nowhere to nowhere doin’? At least the Texas plan is a private venture but, if implemented, I doubt it would remain so
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When working in Europe, often took the train between places such as Brussels and Frankfurt. Although the plane trip was 40 mins and the train 4 hours, in practice the total door-to-door times were similar, and I was able to do a lot of work on the train. After fast trains were introduced between Paris and Brussels, a lot less folks flew that short distance. And the Eurostar is a great service.
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Have you been on the Mag-Lev train from Shanghai to the Airport? It reached a speed of 432 km/hr. Only thing is that only tourist went on it. Not convenient. We did not take it when when flying in from Wuhan. It does not go to the main CBD where our hotel was. I suggest that the cost and inconvenience is an issue for the Chinese business people.
A fast train from Central to Canberra would be a huge loss maker and not all that fast. One is better driving if plenty of time and need a car if from Sydney or the country. If coming from Brisbane or other large cities it will always be better (and cheaper) to fly.
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The downside to these “Miniscule”flight times is the fact that to achieve them the acceleration an decceleration rates will only achieve mass of mangled occupants at opposite ends of the craft depending on whether it is speeding up or slowing down to meet the schedules.
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If you bothered to do some high school physics you’d discover that you are wrong.
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Yes, you can hardly launch or land a rocket at Heathrow or JFK. So the 1 hour flight time is nearly irrelevant.
Concorde was mostly going slowly over Ireland and Newfoundland. The rest was only 1 hour 20 at Mach 2. And the sky above was black and the world a ball. But I would rather takeoff and land in an aircraft at an airport than experiencing the G forces of a rocket. The whole experience was ridiculously luxurious.
But ultimately Concorde failed economically. The final and only crash was not the fault of the aircraft, but an impetuous pilot and a spanner left on the wing. But they were all put out of service immediately.
Few people thought the expense was worth it. Except for the novelty. And even that faded. Plus I found a lot of people were just too scared to fly on it, even if it was free.
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One of my major regrets in life was not managing to fly on Concorde.
We saw the British prototype make her maiden flight from Filton to Faiford. She was always accompanied by a Canberra on her testing flights.
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Fairford
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Annie,
Flew from Heathrow to JFK New York early 80s on the Concorde.
Seat 2A, turned right as I entered BA Check-in Area in Terminal 1, I turned right rather than up to 1st Class Check-in,
felt really great to go behind the “Curtain”
Received solid silver & leather key ring as a memento of the Concorde flight
Very Narrow, but comfortable seat and as we started take-off roll from Heathrow, Captain came on audio to say
Ladies & Gentlemen, we will have the After Burners on as we take-off, soon after take-off, due to noise abatement
requirements, we will turn the After Burners off, and it will feel/sound like we are going to drop from the sky –
do not be alarmed – we will continue without the After burners till we reach the end of the Bristol Chaneel, when
we will re-ignite them and go for Mach 2 and 61,000 Ft
Food, including Caviar amazing and they had a Speed Indicator of Mach above entrance to cockpit which was open and we were
able to talk to crew
At 61,000 Ft the earth was curved, and at Mach 2 the Window felt quite warm
Arriving at JFK one was entitled to a Helicopter transfer from JFK to Helicopter Landing pad on the Hudson River next to the Pan-Am
building – It was the Clearest day I have ever been in New york and the Views were amazing
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PS today I check-in at 1st Class Counter, go into the 1st Class Lounge, then go and board to Economy (Cheapskate that I am), except paid Premium Economy to Dubai A380 on QF Flt Number for Wife, as second leg to Milan on Emirates A380, which has Front Lower Deck Economy with no Premium Ecomomy, with 5 Toilets vs 3 in the same area for Premium
Go Figure
Emirates 1st Class area Dubai excellent as is Cathay Pacific Heathrow and Cathay Pacific Hong Kong 1st Class not Bad
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re: “Few people thought the expense was worth it”. Actually, tbat’s one of the really interesting things about Concorde. It is true that few people thought the expense was worth it, but Concorde did fill their flights reasonably well. Trouble was, they were losing money. Enter Captains Brian Walpole and Jock Lowe who realised tbat the passengers didn’t pay for their own tickets, their organisations did. So up went the ticket price and Concorde became profitable – until a crash that wasn’t its fault.
Indirectly related: I always have to fly from Sydney even though Canberra would be more convenient. That’s because most passengers in and out of Canberra don’t pay for their own tickets, their employer (government) does. So there are no cheap flights out of Canberra.
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I believe at the time the reason for the crash was the square shaped windows which gave way at the corners. Since then all windows are oval or round.
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That was the Comet, not Concorde, which suffered a ruptured fuel tank on takeoff, after running over a strip of metal.
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That’s the most tedious aspect. We are a 2-hour drive to MEL and tired before even starting the airport routine.
Our last journey, while I was still feeling post viral, was a good 5-hour drive from Southern Spain to freezing cold MAD, then the flight to DXB, then DXB to MEL and finally 2 hours to home at night, eyes wide open for roos, wallabies, wombats, deer (including a very large one) and foxes. I’m sick of travelling!
BTW, MEL airport was really quick and efficient, kudos to them I say.
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We are a 2-hour drive to MEL
No sympathies.
Pushing it hard I am 4 hours from Perth. Five is always allowed.
Which is why I will likely never use QF 72 SIN-PER (arrives roughly 00:30).
Once upon a time QF had a flight leaving SIN at 09:00 (I took it three times in 2011).
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Horribly smug here, with the airport at the end of our road, about 1km away. Manned by lovely local people, such a social event departing and arriving. Free parking. 2 hrs flight to Brisbane.
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At one stage in my working life, I seemed to live on QF71/QF72. Home and into bed at 2am, up at 6am next morning, back to work in Perth. Recover over the weekend, then back onto QF71, and repeat the weekly cycle.
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Travel is greatly over rated.
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Why would you want to go to NYC or London?
Forget the speed – they are both Marxist garbage dumps.
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I think Musk will do this.
And as Peter C said above, the door to door time will be much longer taking into account boarding, deboarding, customs, security checks etc.. And getting to and from spaceport.
The fastest London to New York passenger carrying commercial flight was Concorde on February 7, 1996, at 2h 52m 59s.
The fastest flight from New York to London was on September 1, 1974 at 1hr 54m 54s was in the SR-71 (former US spy plane, max. speed about Mach 3.2).
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Why did you start a new comment and not reply to Peter C?
But back to your comment…. It might be faster now with rockets but how about the cost. Concorde was expensive but affordable. How about a Musk flight across the Atlantic. Any idea of a cost?
And what concerns me is the need for security, imagine the bragging rights for the first terrorist who brags about bringing down a rocket.
Sick people exist in this world, it’s not a matter of if but when.
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“boarding, deboarding, customs, security checks etc.”
These were all close to zero for Concorde. You sailed through both ends on red carpets. And only 120 people. You can guarantee the same approach for the same reasons. Plus you had a complimentary Sikorsky helicopter straight into Manhattan. There is now an air train/monorail.
David Frost flew nearly every day for three years to host two shows, one in London and one in New York. The time saving was fantastic for business. For people on holiday, it hardly mattered.
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Complimentary? Really?
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In the sense of a standard ‘gift’ of British Airways, free for Concorde passengers. But they did not publicise it widely as there were only about 20 seats. Otherwise getting into Manhattan was not fast or easy.
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David Frost flew nearly every day for three years to host two shows – today that can be done on line.
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Amazing, but I’m happy to watch these passenger flights when they start and try and take it all into my tiny brain.
I heard Elon say his brain is like a storm and I wonder when he has the time to sleep.
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I wonder if he gets hail in there too.
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Can you imagine George Soros doing this
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The Left never produce, only destroy.
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Yep
Soros made his billions by shorting currency markets, destroying middle-class people’s savings and purchasing power while enriching himself.
Elon made his billions by making cool stuff and advancing human technological achievement.
The fact the political establishment around the world consider Elon the bad guy and Soros the good guy tells you all you need to know about how upside-down the priorities of the political ‘elites’ are.
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With Elon as head of DOGE, I wonder if he’ll still be allowed to run his business?
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Until this thing takes off, anyone have an opinion of Jetstar vs Scoot between Singapore and Perth?
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Yes Mate, neither if you can avoid them would be my advice……!!!
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Depends on how badly you need ~ or SC.
And the direction you are flying combined with the time needed to get to/from the airport.
exPER:
Scoot has two evening flights exFri
Jetstar early am (TuThSa) late pm (TuThSu)
exSIN: PER arrival times are reasonable for me.
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Where in London (or anywhere in the UK) or near New York city would there be a free area with adequate clearance to build a spaceport? I think any launches would have to be offshore from an island (if available) or an artificial island or barge.
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The blast radius would exclude the English channel around southern England. Shetland might be an option. But then you’d need a 4 hour ferry, a 12 hour train trip or a couple of flights.
I’m not seeing the real savings here.
Imagine trying to land near New York or DC.
Note…. travel times above are estimates only.
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I liked the photogenic end of the flight at Turks and Caicos. Just add some parachutes, and you can land at Trafalgar Square 🙂
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London to New York?
Cool.
Just in time.
As both are quickly becoming places where no one wants to go.
Along with LA.
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There’s already movies:
Escape from New York. 1981
Escape from LA. 1996
“Call me Snake.” https://youtu.be/5TH54D2lm9c
Now we need Escape from Londonistan.
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Elon’s vision is for hundreds of Starships in operation, with rapid turnaround like aircraft, continuously launching matériel into space or shipping to Mars.
The Raptor engine, a reinvented rocket engine concept, allows this because it does not need cleaning or rebuilding between uses.
See video on Raptor engine:
https://youtu.be/nP9OaYUjvdE
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How many G’s does the starship apply to your body?
What does the oxygen and cushioned seating cost?
What is the price of a ticket when a human must be provided
with habitable space and survive the trip without injury?
How much is 20 hours worth to you? $10,000 per hour? $20,000 per hour?
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Acceleration at 2G, a relatively safe level, for just over 2 minutes will get you to 10,000km/hr. That will be quick enough for short duration flight to NY from London.
Acceleration won’t be the limit, it’ll be cost.
And the fact that you won’t even get a complimentary glass of champagne during your flight.
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Better check your calculations. Check where Starship flight 7 got to and it was going 21000kph.
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Let’s see, London to New York, 5,500km, (roughly). At 10,000km/hr, that’s half an hour. So flight times are short.
Velocity = acceleration x time.
2g = 20 m/s^2. Time 135 seconds.
So Velocity = 20 x 135 = 2700 m/s Convert to km/hr. Velocity = 9720 km/hr.
Calculations checked. All good.
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Wrong again. Orbital velocity is 8 km/sec and you need to get almost to that to go 5500 km. The ship isn’t under power for very long. Liftoff has thrust to weight of about 1.5 so 0.5g at liftoff (you need to take away acceleration due gravity) and ends up around 3g as fuel is burned. They may throttle the engines for the last bit as g losses aren’t so important.
Flight seven was at 21000 km/hr and went nowhere near 5500km.
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You must be a little slow on this.
No one said anything about orbiting. The whole point is to land not to keep going around.
And if you think you need to be at an orbiting velocity to travel 5000km, then you’d better give QANTAS a call, they’ll need your skills.
The sums I showed indicate that 2g will be sufficient for a timely flight to NY from London. Like most transport systems, a throttle is fitted. In this case, the throttle is used to control the acceleration, cruise velocity and also the slow down at the end.
Have you called QANTAS yet?
With regard to flights by others at 21,000 km/hr. Have you wondered how much of that wasn’t a LATERAL velocity. ie UPWARD.
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How many average people can cope with the G forces involved whithout prior training .
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The Space Shuttle went up to 3G. That was judged to be the appropriate limit for people untrained for high G and without g-suits.
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Correct and 3g is no big deal even if sitting upright. Front to back you’d hardly notice. 5.5g upright is a different matter even with the g suit fully inflated. Greyed out.
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I suspect a good medical exam was required for this 90 year old before his trip into almost space.
I hope both my health and bank account will allow me to be flying at 90.
https://edition.cnn.com/2021/10/13/tech/william-shatner-space-blue-origin-everything-you-need-to-know-scn/index.html
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The g forces top out at around 4g, which is well within an average persons ability to withstand for the minute or so they occur, especially since everyone will be lying down in a couch.
Mind you, they will NEED passengers to have medical clearance to fly regardless.
The bigger issue is the “swoop of death” maneuver and/or the zero g portion of the flight
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The Swoop of Death Manoeuvre?
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The landing without the go around option
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Go watch (youtube) the prototype Starship 5 through 12(? I think, could be 10) sub-orbital hops and (attempted, bar the last) landings..
They practiced getting the Starship from a belly flop to a tail first landing.
Eventually, though, it will be more of a nose first dive to upright… the swoop of death.. you make it, or you go splat.
Just the sort of thing you want the military to test, and get the kinks out of first…
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There was a quiet announcement a couple of months back that the Pentagon were tipping money into the bucket so they could put marines anywhere in the world in an hour.
The only thing not explained at the time was how to get the marines out of a spaceship that could hover for a couple of seconds, but not land. I’m sure they expect Musk will solve that problem for them too.
It does show how accurate missiles are these days, you can come in from space and land within mm using only machinery. ..or you may not bother to slow down…
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Some Starship configurations can land with legs, such as the ones that will land on moon or Mars.
The way people, such as US Space Force Marines, exit will be some sort of elevator type contraption down the side of the vehicle.
Incidentally the US Space Force was established under TRUMP.
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Debarking troops will be using a fast rope, also known as the “Australian” rappel… for show.
Note that fitting landing legs costs you payload mass
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No windows, massive acceleration, fear of these sort of flights and heights, is enough to make me feel really motion sick. Just like his Tesla EV. And what sort of luggage allowance? My wife’s needs in this department are not negotiable!
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Looks like the 2025 Federal election campaign vehicle one-way flight out.
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Hazard a guess at the fuel consumption per passenger?, would make the Concorde look like a bus. This is exactly what the world needs, more joy rides for the rich.
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What’s the problem with fuel consumption or “more joy rides for the rich”?
As long as they pay their own way, I don’t understand what the issue is.
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Sure, as long as no one’s pretending this is for ordinary ‘people.’
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About 1 Ton per passenger. Starship + Booster hold a bit over 1000 tons of methane, most of the propellant mass is Oxygen (3900 tons).
Elon has talked about 1000 passengers. A 20000 km flight at 5 Liters/100km per passenger would use 800 kg of jet fuel.
So for very long haul fights, not much difference in fuel used. Simplistic analysis excludes freight, and the energy required to liquefy the Oxygen.
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Booster won’t be needed for PTP, you’re not actually heading into orbit, so you don’t need that extra kick.
Starship V3 will be 300 tonnes of Methane and ~1200 of Liquid Oxygen.
PTP Starship will likely be V(double digit), by the time it becomes a thing…
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I haven’t been keeping up with all the details, but as I understand it Starship can in theory SSTO but not with any significant payload.
I can’t find a handy reference for suborbital ballistic delta v vs distance but I assume it must be close to orbital velocity. It could be more since you need to launch in the direction of you destination and won’t get the full benefit of the earths rotation.
For shorter hops the required delta v might be low enough that using Starship alone as a single stage might be viable. But for a antipodal trip it’s going to be more economical to use the booster.
The animations I have seen show the booster being used. Has Elon / SpaceX said something different?
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Fuel consumption is a non issue, TBH.(unless you’re a deep CAGW believer)
Methane is substantially cheaper than jet fuel, and liquid oxygen costs depend on your local electricity costs, but still in the cents/kg range.
The important thing is that, compared to a long distance jet, Starship is (once in full production) cheap.
At the moment, a Starship is likely around $20-30 Million to build, which is already substantially cheaper than a 777 or A340, but the aspiration is to get that sub $10 Million.
Keep in mind too, there will NO pilots, a human cannot fly a Starship, so you save big on wages per flight compared to an airliner.
Put your human spam in the can, lock down the restraints, unpack them at the other end 45 minutes later.
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London to NY?
One rotten sh#thole to another in 30 minutes.
Whoopee! 😆
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London is not a sh@thole IMHO.
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Try San Francisco, So much rubbish and homeless on the streets.
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Yeah, it is now.
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You haven’t been there lately,have you?
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Musk is aiming for an Earth to Mars trip rather than London to Melbourne flight
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I watched a documentary about Venus and the planning underway for exploration using humans and stations suspended in the atmosphere, ground level is far too hot and gravity crushed the first landing craft within minutes of landing. Apparently it is believed that the planet could be changed to return to being an Earth-like place as it was a long time ago.
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Exploration of Venus;
https://science.nasa.gov/centers-and-facilities/goddard/nasas-davinci-mission-uses-old-data-to-reveal-new-secrets-venus/
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Venus surface g is 85% that of Earth. The temperature is another matter but high in atmosphere at around 1000 hPa is quite tolerable.
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Perhaps he can rescue the stranded astronauts on the space station……
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They’re not stranded, there’s already 2 seats on a Dragon up there for them.
Which sucks for the 2 astronauts left on the ground, who gave up their seats.
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Who cares? For one thing, ordinary folk can barely afford energy, a situation guaranteed to worsen because our own nation’s appalling political classes, elected and unelected (replicated elsewhere). Ever lower standards of living have become the imperative of these people.
Meanwhile who can take seriously the writers (at SpaceX) who conjured the following:
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Humans still need to be shown visions of what is dreamed, no matter how difficult our lives are (and they aren’t, so far, anywhere near as difficult as those of the silent generation).
Really liked the tongue-in-cheek description of the Starship kaboom. Reminded me of some sci-fi show or film, maybe more than one.
Able to be light-hearted when something like that happens with nobody aboard, thank God.
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(a) SpaceX needs proper clinical trials before I will go on it. (b) Will people notice that SpaceX uses fuel while they have to get their power from wind turbines?
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Get serious, a catastrophic explosion with the re-entry vehicle disintegrating!
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Humans still need to be shown visions of what is dreamed, no matter how difficult our lives are (and they aren’t, so far, anywhere near as difficult as those of the silent generation).
Really liked the tongue-in-cheek description of the Starship kaboom. Reminded me of some sci-fi show or film, maybe more than one.
Able to be light-hearted when something like that happens with nobody aboard, thank God.
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You said it so much better than I did Janet. Well done.
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Humans still need to be shown visions of what is dreamed,
I understand your effort to maintain humanities dream of exploring the solar system (as a first step), but why is it that so much of the internet is short video clips of cats doing what cats do?
This may apply to both the two and four legged versions.
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The gap between what is ‘possible’ and what is ‘practical’ is quite large
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a ‘rapid unscheduled disassembly = It blew up.
A drone can land automatically just like the booster. No big deal. Tell EE-Long he’s dreamin.
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You’ll get there in 25mins or you won’t.
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Presumably they’re working on a tesla motor powered version.
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Remember this is a test program using mostly obsolescent hardware as the design gets iterated.
As for point to point I doubt that Starship is capable of steep entry trajectories as the g loads will be too high as it hits dense atmosphere too quickly as will peak heating be too high.
To go New York London you’ll need to be not far short of orbital velocity at around 100nm.
Say 200km or 200,000 meters. At orbital velocity Earth gravity is balanced by centrifugal force so the ship maintains altitude. If you are at 95% of orbital velocity the centrifugal force is about 90% that of gravity (square law) so a residual acceleration towards Earth of 1 m sec^-2. How long to fall from 200,000 meters to say 100,000 meters where atmospheric effects will begin?
s = 1/2at^2 so rearranging t^2 = 100,000/0.5 =200,000 Square root of 200,000 is 447 so in 447 seconds or about 7.5 minutes you are getting in atmosphere. Add say 7.5 minutes for launch and acceleration and you are still short of London. Note this is when you are at 95% of orbital velocity.
A point to point optimised vehicle might look at lot different from Starship system which is being optimised for lowest cost to surface of Mars.
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Good thing they didn’t leave it to Kamala to report it.
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