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(Note: changed the question title, changed the expedition paragraph to mention weather stability (thx Christopher), voted to reopen, removed additional question section 20-jul)

(Note: some finds regarding the planet as viewed from Earth were possible because below scenario is situated about 150 years from now. There is no magic involved..)

(Note: near-zero means it could not be measured by the expedition on the planet, using 22th century equipment.. "near" was included for physics reasons, zero is impossible)

Discovery

In 2173, a planet is discovered in the "goldy lock zone" of its solar system. Humans would be able to live there, and since we found the planet looking through a worm hole, we know we could send people over, in 1-4 years, depending on the location of earth relative to the entry point. When the entry of the worm hole is reached, we can jump in and warp travel to the planet in a few minutes. The worm hole is stable, so we could jump back as well, but that will be of no use, because with these worm holes, you never know in what epoch you'll arrive.. so it will be one way traffic, but we can get there !

This planet is very special. Thanks to its sun, the surface has a very nice temperature (15-22 celcius) and its atmosphere is earth-like, with similar levels of oxigen and nitrogen. It has water, clouds..

Very old and well protected planet

The worm hole folds most of the universe. This solar system containing the planet, resides about 7 billion light years away from us, the system is ancient. But this wonderful planet ! it's even older.. it did not originate from the solar system it was found in. The planet is estimated to be about 10.3 billion years old. And it has special properties: there is no hot mantle, no vulcanism and it has a stationary massive iron core, embedded in rock.. there seems to be no tectonic plate movement.. the planet's geology has stopped changing some 2-3 billion years ago. It is quiet: no asteroid belt near, despite the ancient surface, there are only very old craters on this planet. There are no radioactive crust elements in its spectrum.. every radioactive element that ever existed on the planet decayed to lighter elements, which are very stable, or have very long decay times. As a result of a relatively fast rotation, there is a magnetic field, which is a few times stronger than the Earth magnetic field. This field does not affect life on the surface in any way, but it forms a perfect shield against cosmic rays. Any molecular oxigen rising in the atmosphere is captured by the magnetosphere and turned into ozone, resulting in a thick ozone layer as well, protecting the surface from harmful UV light from the sun.

Expedition findings

The above was all known from observation, before the first expedition left. They took a small quantum device with them, keeping Majorana particles entangled with Majorana particles on earth. This way, the researchers could communicate their findings. Slowly, but instantly.

In short.. the expedition found weather to be extremely stable, and also, the flora and fauna on this planet to have existed for a very long time, remaining unchanged. The first paleo-biologists investigating the planet found sedimentary layers several hundreds of million years old, containing exactly the same species they found alive. As the expedition was quite short, as a result of a poisoning accident, biologists could not validate their theory, that the stationary ecosystem was caused by a combination of low radiation, stable climate and absent tectonics.. but it seemed plausible ! In a sense, evolution was frozen in time.

Thanks for all help and comments.

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    $\begingroup$ Even if no mutations were occurring, en.wikipedia.org/wiki/Natural_selection will continue to occur, changing the genetic makeup of the species on the planet to better fit environmental conditions. In any case, the absence of radiation does not mean the absence of mutations anyway; see en.wikipedia.org/wiki/Mutagen and note that radiation is only one of many possible sources of mutations. $\endgroup$ Jul 17 at 2:47
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    $\begingroup$ What do you mean by "radiation"? Sometimes it's used in the sense of any sort of photons, but I'm guessing you're talking about something like high-energy photons. Also, the question has quite a few sub-questions, making it a bit broad; I'd recommend breaking those down into individual questions, if possible. $\endgroup$
    – HDE 226868
    Jul 17 at 2:58
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    $\begingroup$ Preventing obvious changes over long periods of time is more a matter of providing stable environmental niches. It's not like "living fossils" don't mutate, the environmental pressures that shaped them for their niche just continue to preserve that shape (at a molecular level, they do continue to change). Stable long-term climate, predictable and consistent weather, maybe quirks in composition leading to a pattern of tectonic activity that keeps the planet living while avoiding large-scale disruptions...allow species to find a niche they can remain well-adapted to without major changes. $\endgroup$ Jul 17 at 4:12
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    $\begingroup$ If you're willing to handwave it, one approach might be to say that the lifeforms have a (fictional) equivalent mechanism to genes based on something other DNA that is much more resistant to mutation and other failures. However, this means the life forms on the planet wouldn't be compatible with human biology in terms of edibility, toxicity, etc. $\endgroup$ Jul 17 at 4:19
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    $\begingroup$ The main source of mutations is life, not external factors. Copying DNA is not a perfect process: there are no perfect processes in this imperfect world. Copying DNA again and againt will introduce errors. Producing gametes and combining them into a zygote will induce genetic variability. Natural evolution on Earth does not in any way, shape or form depend on the feeble amount of background radiation on our planet. $\endgroup$
    – AlexP
    Jul 17 at 8:07
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10.3 Gy is only a little over two U-238 half lives, and not even a full half-life of the main isotope of thorium. That's not nearly enough time to decrease radiation to the point of undetectability.

With a frozen core, there will be little in the way of a magnetic field, and what's left after it freezes will decay faster than uranium or thorium. And even if the magnetic field had some other origin, the magnetic field has nothing to do with the formation of an ozone layer...that's entirely up to the abundance of oxygen and absence of substances that would remove the ozone in the regions of the atmosphere at the appropriate temperature and pressure, the presence of UV from the star, the atmospheric circulation patterns.

Lack of tectonics means loss of processes liberating gases from crust and mantle rock and rebuilding landmasses. Landmasses will slowly erode and become increasingly mineral-poor as necessary minerals accumulate in and under the oceans, the atmosphere will thin, and the oceans themselves will eventually be lost. Once these processes are lost, the environment will become increasingly extreme and hostile to life that evolved with them present. You can expect extremely old planets to be more or less Mars-like, except perhaps with things having been eroded flatter before they dried out.

Also, entangled particles can not be used to transmit information.

All of that aside, for life on Earth, radiation is a relatively minor contributor to mutation. Most mutations are due to biochemistry gone awry: cells are not perfectly reliable and deterministic machines, they are networks of competing and interacting chemical processes that overall tend to drive things in the direction of a functioning metabolism. Apart from simple failures of the mechanisms that handle genetic materials, there's a wide variety of chemicals that can produce mutations, and some of those chemicals are vital parts of cell metabolism. Some organisms even have mechanisms to increase the rate of mutation when under stress, to better adapt to environmental changes.

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    $\begingroup$ This article goes into some detail about a few of the basic errors that can happen during the physical process of DNA replication, without any chemical or radioactive stimulus. $\endgroup$
    – Cadence
    Jul 17 at 3:11
  • $\begingroup$ @Chrisopher James thanks very much for this answer.. it prevents me from writing a story based on an impulse. I tried to stack a lot of "protections" for my planet, shielding it from radiation, but I now realize that would not be so easy.. and radiation would not be the only actor involved ! $\endgroup$
    – Goodies
    Jul 17 at 3:43
  • $\begingroup$ "Also, entangled particles can not be used to transmit information." you're so right, with current insights.. Schrödinger's cat won't allow us to inspect state without breaking entanglement ! but I'm happy to inform you by the year 2173, this is circumvented using the many available majorana particles and statistical methods and signal correction. The result is a steady stream of information, at a very low speed of about 300 Baud, for a limited amount of time. Majorana's are exhausted (used) at some point. On Earth, the faith of the expedition also became known, thanks to the device. $\endgroup$
    – Goodies
    Jul 20 at 1:19
  • $\begingroup$ @Goodies the problem is that Majorana fermions are a class of possible particles described by current theory. They're not mysterious and do not violate the fundamental relations that prevent systems described by quantum mechanics from transmitting information faster than light. In short, while we can't say for certain there's no way to do achieve FTL comms (though we have very strong reasons to think so), we know that quantum entanglement isn't it. You're just propagating an unfortunately common misconception. $\endgroup$ Jul 20 at 23:29

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