You likely know someone who has absolute faith in Musk. They believe he will establish his desired one-million-person Martian colony by 2050. But is this realistic? It is as likely as discovering little green men on Mars? Today, we are going to perform simple math and find out. Let’s begin by determining the minimum number of trips to Mars he needs to make.
Musk has said that he wants a colony of one million people on Mars. He has said that SpaceX will use the Starship launch vehicle for this purpose. SpaceX itself says the crew capacity of Starship is 100 people (SpaceX used to list this number on the Starship website, before removing it). To calculate the number of Starship launches needed for transporting a million people to Mars, divide the colony size by the crew capacity of Starship. We divide one million by one hundred:
$${ {1,000,000 \; people} \over {100 \; people \; per \; launch} }= 10,000 \; launches $$
Therefore, SpaceX must launch 10,000 Starships to get the people to Mars. That is a vast number of launches!
What will a launch cost? And what do launch costs include? The costs include things such as: the cost to build the rocket, test the rocket, infractructure required for th elanuch, fuel and labor costs.
How expensive is a Starship launch? At the time of writing, Musk has said that it costs SpaceX up to $100 million per Starship launch. SpaceX launching 10,000 Starships at present costs yields this calculation:
$$ 10,000 \; launches * $100,000,000 \; per \; launch = one \; trillion \; dollars $$
This gives us an astronomical figure of $1 trillion. SpaceX will obviously not have $1 trillion to spend in the foreseeable future. That is vastly more money than all of its funding, contract revenue and all other income sources combined.
SpaceX made an estimated $13.1 billion in revenue in 2024. Let’s assume SpaceX can sustain similar revenue levels going forward. How long would SpaceX take to earn $1 trillion?
$$ {{$1 \; trillion} \over {$13.1 \; billion \; per \; year}} = 76.3 \; years. $$
SpaceX would need over 76 years to pay for the $1 trillion. Of course, this assumes SpaceX uses 100% of SpaceX revenue for this! Musk claims he wants to launch to Mars by 2050! More like 2100 at the earliest!
But, you say, that $13.1 billion is its revenue from operations. What about the money it gets from investors? What does that amount to? According to this website, SpaceX has received 30 rounds of funding, with all but three of the amounts publically disclosed. The disclosed funding amounts add up to under $11 billion between 2002 and 2023. Therefore, what is the average funding amount per year?
$$ {{$11 \; billion } \over {21 \; years}} = $550 \; million \; per \; year.$$
Let’s add that $550 million to its supposed yearly revenue of $13.1 billion. How long will it take to accumulate $1 trillion?
$$ {{$1 \; trillion} \over {($13.1 \;billion +$0.55 \; billion) \; per \; year}}= 73.5 \; years. $$
Even if we account for all of its known investments, it would take SpaceX 74 years to raise the required $1 trillion! That’s unrealistic; a trillion-dollar raise would consume all revenue and investments. This cannibalization of resources leaves nothing for operations and leaves it no ability to generate the $13 billion of revenue it needs to generate every year!
Musk says he hopes to reduce the cost of Starship launches down to $10 million. They would still require SpaceX to find $100 billion. How SpaceX will finance this project is uncertain. SpaceX would require seven years of revenue for this. Were SpaceX to use all of its revenue, it could do this by 2032. But, obviously it cannot afford to spend all of its revenue on Starship launches.
Musk has said he hopes to reduce Starship launch costs down to $1 million. A launch cost of $1 million is 1% of the current price. I am dubious about this assertion. Should he do this, SpaceX needs $10 billion for launching the Starships. $10 billion is an amount of money they can more realistically hope to find somewhere. Unfortunately, $10 billion is approximately equal to the total amount of funding they have received during their entire lifetime at the time of writing. It is unclear where SpaceX would find enough money to do this, while also funding everything else SpaceX does, such as funding Falcon research.
To travel Mars efficiently, one needs to consider the Mars launch windows. Mars launch windows are the most energy and time-efficient routes between Earth and Mars. They occur when Mars and Earth line up in theirs orbits so as be massively far apart. For Earth and Mars, they occur approximately every 26 months and last between 7 to 9 months. Why is this important? It is important for SpaceX to reach Mars using a launch window, assuming it wants to take the optimally efficient route.
Musk’s goal is to send a million people to Mars by 2050. I write in 2025 and he has 25 years to complete it. You might think that is very doable. But he needs to plan his trips to Mars around these launch windows. How many launch windows does SpaceX have before 2050? They are every 26 months. So, multiply the number of months in 25 years by 12 and divide that 26 months:
$$ { {(25 \; years * 12 \; months \; per \; year)} \over{ 26 \; months \; per \; transfer \; window} }= 11.5385 \; transfer \; windows $$
We get 11.5 transfer windows. Let’s say he has 12 transfer windows to use. That sounds promising! Not so fast.
If he is to meet this 25 year goal, he needs to launch 10,000 Starships within that period. How many Starships does he need to launch per transfer window?
$$ {10,000 \;launches \over 12 \; windows}= 833.33 \; launches \; per \;window $$
I will be generous and round down to 833. So, he needs to launch 833 Starships within each 7 to 9 month window.
This does not seem practical. How many Starships does SpaceX need to launch per month? The best-case scenario is a 9 month window, so let us assume that for every launch window.
$$ { {833.33 \; launches \; per \; month } \over {9 \; months}} = 92.5 \; launches. $$
He needs to launch 92.5 Starships a month. I will round that down to 92 a month. How many must he launch per day?
$$ { {92 \; launches} \over {30 \; days} }= 3.083 \; launches \; per \; day$$
SpaceX requires 3 Starship launches every day for nine months straight. This is the best-case scenario for nine-month windows. Seven-month windows require more Starships a month:
$$ { {833 \; Starships \; per \; month} \over {7 \; months} } = 119 \; Starships \; per \; month.$$
That is 119 Starship launches a month. And how many launches per day?
$$ {{119 \; Starships } \over {30 \; days}} = 3.97 \; Starships \;per \; day.$$
So, SpaceX must make 4 Starship launches every day for 7 months. Does this sound workable to you? Do you believe SpaceX can sustain launches of between 3-4 Starships launches every day for 7 to 9 months? Can he repeat this every 26 months for 25 years? If you consider this doable, I have amazing bridges that might interest you.
Elon Musk founded SpaceX in 2002. Since then, the Falcon 9 family have launched 487 times within its 22-year operational lifespan. If we take the mean number of flights from this, we get 22 rockets per year, or 1.8 flights per month.
However, this does not give us an accurate picture of how many rockets the company launches in more recent times. In 2024, SpaceX launched 134 rockets. That is an average of 11 per month, or 2.75 per week. That is an impressive number of launches. However, it still falls well short of what they would need.
How much better will SpaceX need to do? Assuming it does 4 launches a day, we need to find the number of launches per month and divide that by 11:
$$ {(4 \; launches \; per \; day * 30 \; days) \over (11 \; launches \; per \; month) }= 10.91 $$
To properly use the upcoming Mars launch windows, it will need to launch rockets at 11 times its current average. There is no evidence SpaceX can increase its launch rate by 11 times by the time the first launch window opens.
This puts the nail in the coffin for any 2025 deadline. I am going to nail the coffin down and set it on fire. According to SpaceX itself, the Starship needs to be refueled in space just after launch. The Starship has to wait around in orbit to be refuelled, before leaving for Mars. Each Starship that launches requires several other rockets to be launched. Fuel rockets connect to the Starship rocket into orbit and inject fuel into it. Musk has said it needs 8 such launches, although NASA estimates it is closer to 16. Lets assume that each Starship needs to do this at least 10 times, requiring ten rockets.
We no longer need to launch a mere 3 or 4 Starships every day during the launch windows. No, every day we must launch 10 fuel rockets for every Starship we launch.
SpaceX must launch between 30 and 40 rockets worth of fuel every day for 7 to 9 months. SpaceX will need to perform between 33 and 44 rocket launches every day for between 7 and 9 months!
I will assume they need to launch 33 rockets over seven months. How many rockets must SpaceX need to launch during the 7 month launch window? Let’s find out:
$$ 33 \; rockets \; per \; day * (30 * 7) \; days = 6,930 \; rockets $$
That is 6,930 rockets spread over seven months! SpaceX launched 134 rockets in 2024. That averages out to one launch every 3 days. That falls short of 33 daily rocket launches.
During that seven-month launch window, it will need to launch 50 times as many rockets as it did in all of 2024! How workable does that sound?