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After reading Why did the Ulysses probe reach Jupiter much faster than Galileo? and answers to How many Space Shuttle payloads ended up beyond Earth orbit? and also What's the largest rocket that was carried to space inside a Space Shuttle? I thought of the ISS.

Considering how low mass but high ISP propulsion for smallsats has continued to develop, I realized that the ISS could really be a "launch platform" for spacecraft that will leave Earth orbit. (almost an example)

Question: How many spacecraft deployed from the ISS have escaped Earth orbit? Are there plans for any in the near future?

I chose "beyond Earth orbit" rather than "deep space" so as not to exclude anything that ended up cis-lunar.

uhoh
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    What makes you think any have? To my knowledge they only launch cubesats. – GdD Jan 03 '20 at 08:48
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    Anything launched to the ISS was first launched from Earth, at great cost in dV. Given that, why would the spacecraft leaving Earth stop at the ISS first, instead of just going direct? – Wayne Conrad Jan 03 '20 at 09:53
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    @WayneConrad While that sounds clever, it's not. A smallsat or even a 6U cubesat may be substantially cheaper as cargo in the next delivery to the ISS than to put on a rocket and launch separately. There have been lots of cubesats deployed that way from the ISS already, and a few larger ones as well. The only difference between what's already done routinely and what I've talked about here is a small solar-electric propulsion system. – uhoh Jan 03 '20 at 18:27
  • @GdD what makes you think I think any have? It's simply a question to which zero can be a valid answer, but for contingency's sake I have also asked about plans for the near future. – uhoh Jan 03 '20 at 18:28
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    @uhoh That's a very good point that I hadn't considered. I wasn't trying to be clever, but I freely admit that I did come off like I was. – Wayne Conrad Jan 04 '20 at 01:33
  • @WayneConrad here's a cool example: What ever happened to SpinSat - did it work? – uhoh Jan 04 '20 at 02:36
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    Looking back in time, there was an alternate plan for the Apollo missions that had a transfer vehicle and lander being assembled in Earth orbit, possibly with a space station in support. This was called the Earth Orbit Rendezvous mode, as opposed to the Lunar Orbit Rendezvous mode with separate lander and command modules. – CourageousPotato Jan 05 '20 at 17:19
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    @GdD - I believe you are correct. I'd suggest you make that into the answer. It will be hard to document as you would have to show that no s/c deployed from ISS has done this. (proving a negative) – Carlos N Jan 07 '20 at 22:26
  • @GdD (fixed link) Yes I agree. Proving a negative here would be overly burdensome, so if it's generally accepted that this hasn't happened to date, in this particular case just saying it hasn't based on personal knowledge is probably enough. see this As for "...plans for any in the near future" perhaps the amount of chemical propellant necessary to escape to infinity might make the spacecraft prohibitively dangerous to handle inside the ISS so it would probably have to be solar-electric and would have to slowly spiral out of LEO for a long time. – uhoh Jan 11 '20 at 06:19
  • For some perspective: to leave earth orbit from the ISS would require approximately 3 km/s of delta-v. NASA is going to be loath to allow that much stored energy near station. Even visiting crew and cargo vehicles don't have that much, let alone cubesats, which are first brought inside. – Tristan Jan 14 '20 at 14:26
  • @Tristan for chemical propulsion that certainly rings true, but a cubesat or smallsat could have 3 km/s of solar-electric propulsion, no? The only stored energy would be if the propellant were a compressed gas, but there's iodine 1, 2 and possibly other solids for electric propulsion. That's why I included the (almost an example) in the question. – uhoh Jan 14 '20 at 14:38
  • @uhoh Looking for documentation where I can find it: the cubesat specification paragraph 3.1.6 limits chemical potential 100 watt-hours of stored energy (total, which includes propulsion and batteries -- this is able to be waived according to 3.1.6.1, though). With infinite $I_{sp}$, that corresponds to a hard upper bound of about 850 m/s for a 1 kg cubesat. – Tristan Jan 14 '20 at 14:53
  • @Tristan I'm confused, solar electric uses solar power; you don't need to store much energy in the cubesat's batteries. – uhoh Jan 14 '20 at 14:57
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    @uhoh I wasn't talking about solar electric power in that comment. There isn't a requirement per se on that, but the pressure of your xenon (or whatever) tank will be scrutinized. That said, on a cubesat, you are going to be absolutely constrained by available power. Most ion thrusters require 1kW minimum to function. Given the AM0 solar flux of about 1.4 $\frac{kW}{m^2}$ and a state-of-the-art efficiency of about 30% for space rated solar cells, you're looking at 2.4 square meters of solar array just to power the propulsion and nothing else. Hard to fit even on a 6U cubesat. – Tristan Jan 14 '20 at 15:04
  • @Tristan okay I understand now, thanks! The linked (almost an example) went from GTO to the Moon and that was indeed 1.2 kW but I have faith that smaller scale yet similar efficiency electric thrusters are possible, but I can't show evidence right now and it's late here and I'm calling it a night. I'll do some more reading... – uhoh Jan 14 '20 at 15:10
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    @uhoh For reference, the papers I could find on "low power" SEP referred to power consumption in the range of 5-10 kW. Low power maybe relative to typical SEP, but not low for a smallsat or a cubesat. – Tristan Jan 14 '20 at 15:11

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To Answer your question:

How many spacecraft deployed from the ISS have escaped Earth orbit?

None

Are there plans for any in the near future?

No

A short proof:

Public Sat-Catalog here

You can search by "International Designator = 1998-067" and filter "On-Orbit" you will get every known object released (intentionally or not) by the ISS an the ISS itself.

61 Results (14.01.2020 about 12:00 UTC): 1 object lost, 60 with orbit data orbiting earth.

A short explaination:

Releasing objects (Nanosats) from the ISS you will ALWAYS kick them out in the rear direction. This way they become slower than the ISS, lowering the semi mayor axis thus reducing collision risk in the future. So every object "launched" from the ISS has basically one direction: back to earth.

No one would allow anybody risking the ISS by starting a Cubesat that is designe to cross the ISSs path.

If you want to launch a Cubesat/Nanosat (N-units large) getting out of LEO you would end up cheaper and on an "better" orbit by simply buying a spot on a rocket full of other Cubesats or as a secondary payload with an other launch.

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