and you thought fuel prices down here were bad!
In air refueling is hard.
In space? With the potential of what happens if two craft crash? Might explain the price tag...
Spacecraft running low on fuel could get a refill from an orbital station by the year 2025, according to a startup named Orbit Fab that reckons it can charge $20 million to top up your tank. The American upstart believes there's a market for its planned service because the growing number of companies launching satellites want …
It presents a different set of challenges with some intersection. In aircraft, you have the issues of interfering aerodynamics and mismatched cruise speeds (especially if a fixed wing is supplying fuel to a helicopter), which are absent in space. For spacecraft, you have to do orbital intersections before final fine manoeuvres to dock, with the ever present risk that thruster failure during gap-closing manoeuvres might slam your craft together. In 2D, it's a bit like the difference between transferring fuel between cars with a minimum speed vs transferring objects between people on an ice rink, blasting around with CO2 extinguishers.
KSP is a fun way to learn about the latter and will nicely illustrate why they're using service shuttles rather than moving the whole fuel platform or expecting the satellites to come to them.
cost per kg of fuel to deliver it from Earth to the orbiting fuel station, plus fuel delivery bots that ALSO consume fuel, cost of earth-bound operators and all of the infrastructure, and THEN you have to make a profit to pay back the investors. That kinda justifies it.
Plus when you are the ONLY fuel station for 36,000 km you can charge "whatever the market will bear"
(I suppose getting a "tow" might be an interesting add-on service - to put a satellite back into orbit if it runs out of fuel and cannot do station keeping for some reason).
Still cheaper than a NEW satellite.
300 km is the altitude where the fireball will be visible. The cause is a big boom which will propel the surviving debris(*) up into higher orbit and, with some luck, all the way to GEO.
(*)That is why they already have the debris removal firm as customer. It is about symmetry of work. One has it, the other provides it, for the other to have it, to be provided, etc..
I assumed they meant it orbited 300km below GSO. That would have it slowly moving around the Earth rather than staying over one spot, to allow it to visit any GSO location on a regular basis - since you don't want to waste fuel maneuvering from satellite to satellite when you can have them "come" to you.
That's typically how GSO satellites move from one position to another - they duck a bit closer to the Earth until the location they want to be comes up and then raise orbit to their new slot. They typically move closer because ~300 km above GSO is the "graveyard orbit" where GSO satellites are retired.
"I assumed they meant it orbited 300km below GSO."
The linked article says it will orbit 300km above GSO, so close enough. "Just below" the graveyard orbit apparently. I guess they go with that direction so it doesn't get in the way of satellites using the lower orbit to reposition themselves, and if something goes wrong with the refuelling then you're already in the right place. It appears to be a mistake by the author here at El Reg that puts the orbit 300km from Earth.
Ever since I saw the moon landing as a kid I have been waiting for our Glorious Flash Gordon Space Future to happen. Waiting desperately for Humanity to finally leave this asteroid-target before it's too late.
It's constantly been held back by shortsighted self-serving politicians and, well... idiots.
Anything that helps get us Out There a bit farther or assist the devices already in-flight is a massive plus.
"andy 1??", et al, the floor is yours... <yawn>
"It's constantly been held back by shortsighted self-serving politicians and, well... idiots."
While there is a lot of that to go around. We're also held back by the science. It's one helluva hostile environment outside the safety of Biosphere 1. And your body rather likes gravity. A Flash Gordon Future is not on the cards.
Still, this is epically cool and should be done.
How does one get the hydrazine up there to refuel the refuling platform?
Several issues spring to mind... not least showering the earth in burning hydrazine in the event of a RUD on the pad, or later in the flight.... it's lovely stuff just the sort of thing to ruin your day completely.
I guess you could make the stuff in orbit providing the process is automatic and the reagents required are less problematic than the N2H4 itself.
Not just rocket science but chemical engineering. All good popcorn worthy stuff, unless this project is just a venture capital black hole....
There is a long list of rockets that use unsymmetrical dimethylhydrazine and dinitrogen tetroxide as propellants. Use one of those and no-one is going to care about a few hundred kilos of hydrazine in the middle of a RUD. Even better, some launch providers dump their first stages (with residuals) on nearby villages by design. None of the locals complain about that any more.
It's a good idea. Throwing satellites away because their tank is empty is a waste and there's enough junk in space.
Northrop's Mission Extension Vehicle is an interesting solution too. Maybe would it be also possible to add a "plugin" to existing satellites to extend their lives?
Anyway, it goes in the right direction.
== Bring us Dabbsy back! ==
An interesting idea, but one that is probably going to have to wait a few years before being useful.
And I mean, a few years after it is in orbit.
I don't think that todays' satellites are capable of being refueled - but I don't know for sure. Once the orbital station is in place and has published its fueling procedure, maybe satellite makers can take that into account but, today, nobody has planned for that and planning is everything where a satellite is concerned.
It's a good idea, for sure, but I have the feeling the company is going to need to survive at least twenty years before actually starting to make any money.
Today's satellites? No.. However there is the RAFTI standard interface that did a test flight last year. It's backed by a group of about 30 companies as far as I remember and supports most non cryogenic fuels that you'd find on orbital birds these days: MMH, UDMH, NTO etc.
Early days sure, but far advanced by space standards!
Yeah that was my question that they don't seem to bother explaining, or at least it isn't mentioned in the article. Maybe satellites built by a certain company (i.e. Boeing, Airbus, etc.) each have their own system for fueling Earthside, but being compatible with even one major manufacturer's "standard" would give them plenty of potential customers. Compatibility with more than one is a bonus.
Engineers designing mil spec/aerospace stuff seem to have some pretty tight standards, i.e. rather than "1/8 turn beyond hand tighten" or similar someone doing trades here might see they'd specify the exact amount of torque to tighten every bolt and screw. So perhaps whatever closure method the fuel tank uses can be relied upon in a similar way, making it possible to design something that if it opens one should open them all. So hopefully no worries about running into a satellite where the guy closing the fuel port gave it a few extra twists to "make sure it doesn't shake loose during launch" or whatever lol!