### Author Topic: [Historical prices] Expenses to send 1 kg to another planet  (Read 2989 times)

#### john22

• Member
• Posts: 2
• Liked: 0
• Likes Given: 0
##### [Historical prices] Expenses to send 1 kg to another planet
« on: 02/05/2016 05:41 PM »
I'd be interested to know how much it would cost to send a kilogram from Earth to Mars. A simple (x;y) table or graph relating year to cost/kg.
From the beginning of space travel until today. I believe we could get a graph out of this and analyze past behavior, as well as (roughly) estimate future trends.
I can't seem to find this information anywhere. I know, for example, that the Curiosity rover has 900 kg of mass and cost \$2.5 billion, but that cost also accounts for research&development and other stuff. I'm asking about the cost of fuel + spacecraft + personnel working on the ground assuring the cargo successfully reaches Mars.

A question that arrives from this is: does the distance of the journey matter? I present 2 cases here:

1) Spacecraft consumes fuel to leave the Earth atmosphere and some more fuel to get on the right track to Mars. Engines shut off for the next 8 months. It reaches Mars and reignites the engines for re-entrance.

2) Spacecraft consumes fuel to leave the Earth atmosphere and some more fuel to get on the right track to Neptune. Engines shut off for the next 7 years. It reaches Neptune and reignites the engines for re-entrance.

So would the fuel consumption for reaching Mars and Neptune be the same? Is the price the same, no matter which planet we want to reach, assuming we're sending cargo? Or am I missing some other kind of cost besides fuel?

I believe those are difficult questions to answer, but as rough as the answers are, it could still provide a good discussion.

« Last Edit: 02/05/2016 05:51 PM by john22 »

#### shooter6947

• Full Member
• Posts: 107
• Idaho
• Liked: 75
• Likes Given: 468
##### Re: [Historical prices] Expenses to send 1 kg to another planet
« Reply #1 on: 02/05/2016 05:54 PM »
I'd be interested to know how much it would cost to send a kilogram from Earth to Mars.

So would the fuel consumption for reaching Mars and Neptune be the same? Is the price the same, no matter which planet we want to reach, assuming we're sending cargo? Or am I missing some other kind of cost besides fuel?

No; the price would not be the same.  You need more fuel to start in on your trajectory to Neptune than you do to Mars.  A lot more, because the transfer orbit to Neptune is much more energetic.  This could be brought down by use of gravity assists, but at the cost of complexity and time.  There's also somewhat of a factor for travel time, as keeping people around to monitor the spacecraft costs money.

None of this includes the cost of ARRIVAL, which you also seem to indicate you want included.  Mars landings end up with these complicated Rube Goldbergian devices with heat shields, parachutes, and rockets.  If you actually want to do a Neptune entry that could potentially be difficult to find the right heat shield material and to get a precise enough entry that you wouldn't either burn up or skip off the atmosphere.  Difficulty of entry into an atmosphere varies:  Titan is really easy, Jupiter is really hard.

#### whitelancer64

##### Re: [Historical prices] Expenses to send 1 kg to another planet
« Reply #2 on: 02/05/2016 05:58 PM »
Adding in mission operations costs will obscure the data you're looking for.

A more focused question is how much does the launch cost, then it's an easy calculation of cost of launch / kgs sent to Mars.

There's an old saying, "once you're in Earth orbit, you're halfway to anywhere in the solar system." It's not much more, in terms of dV, to break out of Earth orbit and get to most places in the solar system as it is to get to Earth orbit in the first place. With the clever use of transfer orbits and gravitational assists, you can reduce the fuel requirements, too.

I think you're looking at too many variables. If you can focus what you really want to find out into one or two questions, it'll be much easier to do an analysis.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

#### john22

• Member
• Posts: 2
• Liked: 0
• Likes Given: 0
##### Re: [Historical prices] Expenses to send 1 kg to another planet
« Reply #3 on: 02/05/2016 06:05 PM »
So I believe the question boils down to:

How much does it cost to launch 1 kg into outer space?
And how much did it cost in 2015? 2014? 2013? And so far until this was possible for the first time.

Does anyone know where to get hold of such information?
« Last Edit: 02/05/2016 06:06 PM by john22 »

#### DarkenedOne

• Full Member
• Posts: 954
• Liked: 58
• Likes Given: 8
##### Re: [Historical prices] Expenses to send 1 kg to another planet
« Reply #4 on: 02/05/2016 07:10 PM »
I'd be interested to know how much it would cost to send a kilogram from Earth to Mars. A simple (x;y) table or graph relating year to cost/kg.
From the beginning of space travel until today. I believe we could get a graph out of this and analyze past behavior, as well as (roughly) estimate future trends.
I can't seem to find this information anywhere. I know, for example, that the Curiosity rover has 900 kg of mass and cost \$2.5 billion, but that cost also accounts for research&development and other stuff. I'm asking about the cost of fuel + spacecraft + personnel working on the ground assuring the cargo successfully reaches Mars.

A question that arrives from this is: does the distance of the journey matter? I present 2 cases here:

1) Spacecraft consumes fuel to leave the Earth atmosphere and some more fuel to get on the right track to Mars. Engines shut off for the next 8 months. It reaches Mars and reignites the engines for re-entrance.

2) Spacecraft consumes fuel to leave the Earth atmosphere and some more fuel to get on the right track to Neptune. Engines shut off for the next 7 years. It reaches Neptune and reignites the engines for re-entrance.

So would the fuel consumption for reaching Mars and Neptune be the same? Is the price the same, no matter which planet we want to reach, assuming we're sending cargo? Or am I missing some other kind of cost besides fuel?

I believe those are difficult questions to answer, but as rough as the answers are, it could still provide a good discussion.

John no one is advertising prices to get to Mar's or anywhere else in space, so a year by year price does not exist.  You can try to estimate the cost based on publicly available information regarding missions to Mars, but a significant amount of time can pass between missions, so estimating the cost for a particular year will be fairly inaccurate.

#### Hotblack Desiato

• Full Member
• Posts: 356
• Austria
• Liked: 67
• Likes Given: 52
##### Re: [Historical prices] Expenses to send 1 kg to another planet
« Reply #5 on: 02/09/2016 11:49 AM »
There is something else to take a look at.

Do you want to calculate all the mass that reached mars? Or just the part that reaches the surface intact? Or the scientific payload.

For example, let's take a look at the Curiosity Rover.

The rover itself had 899kg mass. Quite obviously that made it to Mars.

The whole system including cruise stage, heatshield, parachute, skycrane and fuel had 3,893kg. And all of it made it to the surface of Mars. Most of it landed hard, the fuel obviously was burned and the exhaust got mixed with the atmosphere (basically that counts as "on Mars" too). Scientific payload something about 50kg.

It's even worse for the MER-rovers: 1063kg total mass of the whole setup that entered the martian atmosphere, 185kg for the rover itself (The lander was just a metal shell and airbags, that folded open, got disconnected and was dead afterwards). Oh, by the way, 5kg of scientific payload.

So in terms of efficiency, the MSL was way more efficient than the MERs, when it comes to the fraction of useful landed mass to total mass and scientific payload to useful landed mass.

Regarding the pricetag: total cost of mission vs landed mass doesn't really work, the payload itself had a rather high value. I've read figures that the RTG of Curiosity itself has a value of about a billion US\$. A calculation of launch costs vs landed mass would work. And here, the Atlas V used by Curiosity is more expensive than the Delta II used by the MERs.
« Last Edit: 02/09/2016 11:58 AM by Hotblack Desiato »