I’m not taking about the ecospheres by the brand “ecosphere”, but the type you see on the channel life in jars. These type of ecospheres are essentially a sealed clear container with water, dirt, plants and other natural materials filled with life placed into it. These are typically a few liters in size, however they can be larger or smaller.

Let’s suppose that these are sent out in random directions at the same speed as voyager 1, and that they have some built in way to safely land on any object they reach.

Take into account:

  • The effects of 0g on life inside them
  • The materials that the ecospheres would need to be constructed out of
  • The effects of the temperature on life in them
  • The life that would need to be placed into them
  • The light they would receive

Do not take into account:

  • Anything after they reach a celestial body
  • The effects of getting flung at such fast speeds
  • $\begingroup$ Sent from where? If from Earth, they'd all be dead in less than a minute, it's pretty hot in the direct sun around here. If in shade, then they'd get frozen and bust as the ice expands. Could you clarify? $\endgroup$ Jan 12, 2022 at 19:30
  • $\begingroup$ Sent from earth yes $\endgroup$
    – Topcode
    Jan 12, 2022 at 19:35
  • 1
    $\begingroup$ The characteristics of the spheres are critical to answering this question. Can you edit the question to provide a description of the spheres so that we're not relying on external links to be able to understand and answer the question? $\endgroup$
    – sphennings
    Jan 12, 2022 at 19:46
  • 4
    $\begingroup$ Aaah, I love the smell of panspermia in the morning. It smells like...primordial ooze. $\endgroup$
    – Zeiss Ikon
    Jan 12, 2022 at 19:57
  • $\begingroup$ @sphennings done, I hope that clarifies it. $\endgroup$
    – Topcode
    Jan 12, 2022 at 20:17

3 Answers 3


The effects of 0g on life inside them

It means no convective flow and no recirculation of gases apart from diffusion. Without a fan blowing around their head, astronauts would suffocate while sleeping in a bubble of CO2 they breathe out.

The effects of the temperature on life in them

Scorching hot close to Earth, then a couple of K for most of the trip: basically you are burning a pizza, deep freezing and then thawing it.

The life that would need to be placed into them

We know that tardigrades are pretty sturdy and that some bacteria might survive in the lunar environment for some time. We know nothing about entire ecosystems.

The light they would receive

It goes with the temperature: a lot of (dangerous) light close to Earth, than nothing but cosmic rays for most of the trip.

Basically, if the sphere has no systems for controlling temperature, light/radiation exposure and gas circulation it will be sterilized by space within hours from the departure. A safe landing is the least of your concerns.

  • $\begingroup$ I think you may have partially misunderstood what the question is about. I have edited it to hopefully clarify. $\endgroup$
    – Topcode
    Jan 12, 2022 at 20:18
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    $\begingroup$ Agree in practical terms re higher life (+1), but relevant xkcd what if what-if.xkcd.com/117 $\endgroup$ Jan 12, 2022 at 22:21

No. The successful ecospheres that have been posted online always have a component of some plant or another. It requires photosynthesis. This requires light.

Significant levels of light.

All the other issues you mention (gravity, heat, etc) might be hand-waved away, but without sufficient light to bring energy into the closed system, it will die in short order. Even the heat itself might possibly be imparted by burning calories metabolically, if you found the right balance of size and radiative surface.

Though I'm not nearly clever enough to do it, I suspect there is a "habitability zone calculation" that defines how far away one of these things could orbit from our sun, and that if an ecosphere were to leave that zone for anything more than a short period of time, it will die from insufficient photosynthesis. This might or might not be simultaneous with freeze-over... because once the organisms start dying back, there's less metabolic heat in the system.

Given that the nearest celestial bodies that might be capable of supporting any such life are light years away, these things will be goners millions of years before they ever find a place to land.


You are missing the absolute biggest concern: Energy.

A first approximation of a system is to grab one of those ecospheres as portrayed in the link provided. Place ecospheres into a steel pressure vessel. The pressure vessel would need to have some space for lighting and heating. The system would need to be maintained within say +-5K of target temperature or it should be considered a failure.

The voyager probes are traveling about 4au/year which is about 16Kyear per light year. 63 thousand years if it were aimed at Alpha Centauri. Space is really BIG. So the system needs a power supply rated to last at least about 100 million years if using random directions within the milky way.

External light in terms of Watt/sec is zero. So only thing plausible is nuclear. Preferably a nuclear fusion power plant. Additionally with a fusion plant, slowing down on the other end is much easier.

Second big concern: Maintenance.

Since this is to operate on the order of 100 million years an automated maintenance system would be a very good thing. Would it have enough spare light bulbs?


Due to the uncertainties of huge time frames, large expense for zero financial return, I would rate this as not realistic.


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