The Goldilocks zone???

Plug · 24-12-2010 12:23am #1

Most of us know what the Goldilocks zone is, its where its not too far from the host star where water will freeze and not too close that it will boil away.
I mean for instance we can be -10c and Spain maybe 1500 miles away could be 15c. In space 1500 miles is absolutely nothing. For a planet to be in the goldilocks zone how precise most that distance be, seems very?

NoQuarter · 24-12-2010 12:29am

Good question, I often wonder this myself!

Mahatma coat · 24-12-2010 12:59am

Like when they describe something as a Class - M Planet in StarTrek. what are the paramaters and how much wiggle room is there?

The Wiki isnt very helpful.
http://en.wikipedia.org/wiki/Goldilocks_planet

maybe someone has a few simple diagrams that will make the concept easier to grasp.

slade_x · 24-12-2010 2:18am

Goldilocks zone, just out of curiosity whats the average age of posters here

Its called the habitable zone for us adults

http://en.wikipedia.org/wiki/Habitable_zone

The easier version:

https://www.e-education.psu.edu/astro801/content/l12_p4.html

www.e-education.psu.edu wrote:

Another visualization of the habitable zone is shown below.
The red region is too warm, the blue region too cool, and the green region is just right for liquid water.
Because it can be described in this way, sometimes it is referred to as the "Goldilocks Zone," too

Suffice to say the habitable zone is quite large for our sun

NoQuarter · 24-12-2010 11:54am

Thanks for that slade.

the OP raised a good point though, as you say the habitable zone is quite big, but the temperature difference at one end of the HZ to the other must be massive bearing in mind that the OP pointed out the difference in the distance from spain to norway can be circa 30 degrees and were only talking about a thousand miles or two.

So as humans, is our habitable zone much much smaller?

maninasia · 24-12-2010 3:53pm

The Goldilocks zone, based on one example, Earth, that's not very scientific isn't it. Liquid water can be sustained by many different means, there are even bacteria on earth that use antifreeze to create their own pockets of liquid water microenvironments from the ice around them (look up the Oort cloud, tell me what it is made of). Radioactivity and gravitational forces can create liquid oceans/lakes. Finally who is to say that our type of life is the most prevalent?

BTW, there could well be life on Saturn's moons and they are not in the Goldilocks zone.

Plug · 24-12-2010 3:56pm

answers.com wrote:

Because of earth's elliptical orbit around the sun, the distance changes over the course of a year (one complete orbit of the sun):

We are closest at perihelion, during winter in the Northern Hemisphere (around January 3rd) at the minimum distance of 147 million km (91 million miles).

We are farthest away at aphelion, during summer in the Northern Hemisphere (around July 4th) at the maximum distance of 152 million km (94.5 million miles).

So there's about 3.5 million miles of a difference during the year, which is quite big. Maybe the small temperature change in relation to 3+ million miles has something to do with the atmosphere keeping the heat at a more or less constant temperature?

maninasia · 24-12-2010 4:09pm

Plug wrote: »

So there's about 3.5 million miles of a difference during the year, which is quite big. Maybe the small temperature change in relation to 3+ million miles has something to do with the atmosphere keeping the heat at a more or less constant temperature?

The Earth seems to switch through different stable climatic states, ice ages, snowball earth, Jurassic tropical period etc. This may be influenced by some type of physical 'balancing' process and I suspect it is influenced by bacteria and plantlife too which may be working together (not in a concsious system but as something that evolved from a complex system) to stabilise the environment or minimise temperature fluctuations and therefore perpetuate itself (Gaia hypothesis, e.g. potent greenhouse gases such as methane and CO2 are regulated by the biosphere in a stable state, outside influences such as volcanic eruptions or meteor collisions may throw this equilibrium out of whack and move Earth into an alternative equilibrium, this might sound 'hippyish' but the science is pretty sound, for instance most rocks on Earth have oxygen and therefore their mineral content determined by plant emissions billions and millions of years ago..the influence of the biosphere cannot be ignored!).

Finally the large amount of water on Earth's surface may help to regulate temperature, acting as a heat sink or insulator.

slade_x · 25-12-2010 3:21am

NoQuarter wrote: »

but the temperature difference at one end of the HZ to the other must be massive bearing in mind that the OP pointed out the difference in the distance from spain to norway can be circa 30 degrees and were only talking about a thousand miles or two.

Theres a bit of a difference between comparing the two, from one perspective you have the region around the star that would keep the average temperature (keeping in mind the average as the whole of earths surface) above freezing where liquid water can exist and the difference in the angle of the earth in its orbit around the sun. the polar regions are naturally uninhabitable for humans. the tropics and termination regions of the arctic circle are habitable. the tilt of any planet orbiting its star has a significant impact also on what would make a planet habitable

the difference between norway and spain is simple, one is in the tropics that receives the most sunlight per year where as the other is a lot closer with parts in the arctic circle which arguably recieves the least. There is a very delicate balance between both. if the earth were to drift further outward the arctic and antarctic circles would just become larger proportionately to the distance. leaving the habitable zone altogether would render the tropics unhabitable as the they would just disappear, plunging the planet into a constant winter where no part of the planet would be habitable for us without our technology.

maninasia · 25-12-2010 8:09am

Yes, but even if ice covered the whole of the earth as long as liquid water existed underneath it or in pockets (which it surely would around geological hot spots and underground where pressure/temperature is higher) then there would still be plenty of life.
So that's why the idea of the goldilocks zone is plainly wrong!
In fact the earth has had a 'constant winter' over large parts of it's history, at one point being snowball earth, http://en.wikipedia.org/wiki/Snowball_Earth, life continued.

bonkey · 25-12-2010 2:41pm

maninasia wrote: »

life continued.

Exactly. Life continued.

That is distinct from saying that these conditions are suitable for life to begin.

They may be, of course. Its also worth pointing out that the habitable zone doesn't define conditions where life is possible, but rather conditions where the odds appear better for certain forms of life to exist.

slade_x · 25-12-2010 4:56pm

maninasia wrote: »

Yes, but even if ice covered the whole of the earth as long as liquid water existed underneath it or in pockets (which it surely would around geological hot spots and underground where pressure/temperature is higher) then there would still be plenty of life.
So that's why the idea of the goldilocks zone is plainly wrong!
In fact the earth has had a 'constant winter' over large parts of it's history, at one point being snowball earth, http://en.wikipedia.org/wiki/Snowball_Earth, life continued.

the habitable zone (HZ) is the distance from a star where an Earth-like planet can maintain liquid water on its surface[1] and Earth-like life. The habitable zone is the intersection of two regions that must both be favorable to life; one within a planetary system, and the other within a galaxy. Planets and moons in these regions are the likeliest candidates to be habitable and thus capable of bearing extraterrestrial life similar to our own. The concept generally does not include moons, because there is insufficient evidence and theory to speculate what moons might be habitable on account of their proximity to a planet.

The habitable zone is not to be confused with the planetary habitability. While planetary habitability deals solely with the planetary conditions required to maintain carbon-based life, the habitable zone deals with the stellar conditions required to maintain carbon-based life, and these two factors are not meant to be interchanged.

The habitable zone does not describe a zone where any kind of life could exist anywhere on a planet. we honestly have no idea of other forms of life out there and what condition they require to live. The habitable zone is an aid to find a planet a little like our own in safe zone around its host star, with life thriving on its surface (idealy advanced life that has evolved on its surface)

And the earth has had extremely long periods of winter lke ice ages and mini ice ages yes, but there are not a constant by the very definition of the word constant.

namloc1980 · 25-12-2010 7:12pm

maninasia wrote: »

Yes, but even if ice covered the whole of the earth as long as liquid water existed underneath it or in pockets (which it surely would around geological hot spots and underground where pressure/temperature is higher) then there would still be plenty of life.
So that's why the idea of the goldilocks zone is plainly wrong!
In fact the earth has had a 'constant winter' over large parts of it's history, at one point being snowball earth, http://en.wikipedia.org/wiki/Snowball_Earth, life continued.

Following on from this there is very strong evidence that there is a liquid sub-surface water ocean under the surface of Europa, one of Jupiter's moons. It is believed that the water is kept liquid through tidal stretching of Europa's interior by Jupiter's massive gravitational well. Europa is a long way away from the Goldilocks zone.

maninasia · 26-12-2010 1:29pm

bonkey wrote: »

Exactly. Life continued.

That is distinct from saying that these conditions are suitable for life to begin.

They may be, of course. Its also worth pointing out that the habitable zone doesn't define conditions where life is possible, but rather conditions where the odds appear better for certain forms of life to exist.

So that should be stated clearly, as a lot of people take it to mean 'life' in general. Plus we only have a dataset of one to base our theories, theories which may well be totally off it we could look at the subsurface of Mars or Europe for example or if we could examine the comets and ice in the oort cloud.
I mean if it was such a 'goldilocks zone' how come Venus and Mars aren't obviously crawling with life, I think the whole idea is way too simplistic.

I think my point about snowball earth and million year long ice ages along with switches between reducing and oxidising atmospheres shows that life can exploit a wide range of conditions.

Johnmb · 26-12-2010 1:57pm

maninasia wrote: »

So that should be stated clearly,

It is stated clearly if you do the research. Of course, if you are just relying on a paraphrase from an article in a non-technical paper, then you clearly aren't getting the full story.

maninasia · 27-12-2010 3:52am

It's a dodgy theory lads...

Johnmb · 27-12-2010 2:04pm

maninasia wrote: »

It's a dodgy theory lads...

It's actually a pretty sound theory. "If we want to find an Earth-like planet that has Earth-like life on it, where should we look?" - "Look in an area around the star that is very much like the area around the Sun that Earth is in".
Very simple, and very obvious. We only have one example to go on. As already stated, the idea does not, in any way, preclude life from existing or beginning in any other areas, it is specific to Earth-like life on Earth-like planets, and the areas that, based on experience of one, we would be most likely to find them.

maninasia · 28-12-2010 2:58am

But Earth life survived snowball earth for millions of years and massive ice ages. A large amount of the biota on Earth is living underground in the rocks (microbial life).There is no strict requirement for habitable zone as stated even for life on Earth. Dodgy theory.

Johnmb · 28-12-2010 1:04pm

maninasia wrote: »

But Earth life survived snowball earth for millions of years and massive ice ages. A large amount of the biota on Earth is living underground in the rocks (microbial life).There is no strict requirement for habitable zone as stated even for life on Earth. Dodgy theory.

Erm.... Earth never left the habitual zone, even during those periods. Theory still stands, the only example of Earth-like life evolving on an Earth-like planet happened on Earth, and the most likely place to find other Earth-like planets that may have Earth-like life evolving on them is is a similar zone around other stars as Earth is in around the sun. Snowball Earth doesn't mean there was no liquid water btw. And the main thing is stability. Over its history, Earth has been remarkably stable temperature wise, so life could evolve into ever more complex forms. While life can/probably has evolved on less stable planets, and on planets that are much more extreme than Earth, the habitual zone relates specifically to Earth-like life on Earth-like planets. I'm not sure why you don't seem to be able to get your head around that.

maninasia · 31-12-2010 12:41pm

I know very well the idea of 'golidlocks zone', I think it is ridiculous as nobody knows how to set the inner and outer parameters of such a zone. As I mentioned already the total amount of water on the planet could act as an insulator resulting in Earth's supposed low variation in temperature aswell as influence from biological life in maintaining a certain temperature range ....but as is well known now life exists in a wide temperature variation on Earth. In addition, planets with a frozen surface could easily spawn life or maintain a huge liquid ocean due to various geological processes....it is not neccessarily related to distance from the sun (within very loose parameters). To a subterranean dweller huge temperature variations in the surface atmosphere may have little or no effect! Finally life could be more common on moons than planets, too many things are unknown still.

Here's another question , what about the influence of active tectonics? Mars doesn't have active tectonics now. Maybe tectonics is the answer? TOO many unknowns.

Bohrio · 02-01-2011 3:24am

maninasia wrote: »

I know very well the idea of 'golidlocks zone', I think it is ridiculous as nobody knows how to set the inner and outer parameters of such a zone. As I mentioned already the total amount of water on the planet could act as an insulator resulting in Earth's supposed low variation in temperature aswell as influence from biological life in maintaining a certain temperature range ....but as is well known now life exists in a wide temperature variation on Earth. In addition, planets with a frozen surface could easily spawn life or maintain a huge liquid ocean due to various geological processes....it is not neccessarily related to distance from the sun (within very loose parameters). To a subterranean dweller huge temperature variations in the surface atmosphere may have little or no effect! Finally life could be more common on moons than planets, too many things are unknown still.

Here's another question , what about the influence of active tectonics? Mars doesn't have active tectonics now. Maybe tectonics is the answer? TOO many unknowns.

I think that what's happening is that ur not really listening to what people are saying

U seem to think that life can only exist inside the habitable zone

maninasia · 02-01-2011 9:10am

I usually don't bother responding to people who don't make an effort to write properly but do yourself a favour and read my posts, especially the last one...you seem mightily confused.

Johnmb · 02-01-2011 4:24pm

maninasia wrote: »

I usually don't bother responding to people who don't make an effort to write properly but do yourself a favour and read my posts, especially the last one...you seem mightily confused.

He's right though, you seem to be ignoring everything that other posters have told you. You are still making statements giving reasons why the Habitual Zone is wrong because of the variety of temperature within it and the fact that life can exist outside it, despite it being made clear that the habitual zone doesn't say that life will only evolve within that area, nor does the idea say that life will evolve within that area. It's a very simple concept, which you don't seem to understand. Other posters have tried to explain it to you, yet you still persist in repeating the same irrelevant "problems", even though they do not actually provide any problems to the idea of a habitual zone, or the reason such a zone has been proposed.

maninasia · 03-01-2011 3:57am

He's can't even write properly and he hasn't even read what I wrote, he's right about nothing.
I've never mentioned anything about a habitual zone, we are talking about the bogus goldilocks zone and how it is not a very useful idea and could very well be very misleading. Look at the moons around Saturn and Jupiter for example, look at what we know and don't know. Mars is in the goldilocks zone near Earth, has fairly similar chemistry and size, the main difference is that on Mars tectonic activity seems to have stopped a very long time ago. Then there is organic material in comets..that obviously could be a suitable living environment for some bacteria. It seems some people don't like they were called up on the shortcomings of a mediocre idea.

maninasia · 03-01-2011 4:08am

Johnmb wrote: »

It's actually a pretty sound theory. "If we want to find an Earth-like planet that has Earth-like life on it, where should we look?" - "Look in an area around the star that is very much like the area around the Sun that Earth is in".
Very simple, and very obvious. We only have one example to go on. As already stated, the idea does not, in any way, preclude life from existing or beginning in any other areas, it is specific to Earth-like life on Earth-like planets, and the areas that, based on experience of one, we would be most likely to find them.

Mars is as earth like as they come smack bang in the middle of the goldilocks zone, it's not exactly swarming with life now is it (not that there isn't life in the subsurface), there are other candidates like the moons of Saturn and Jupiter that have just as attractive chance as Earth-life life.

I notice how the argument starts stressing Earth-like life now..but bacteria can exist in a massive range of different environments as we well know..what is 'earth like conditions' per se? Some bacteria prefer CO2 environments, some prefer O2, some break down methane, some take energy from radioactive sources and sulphur, some resist high doses of radioactivity, some can remain dormant for perhaps millions of years, some can survive long periods of vacuum, many live in colonies creating their own minienvironments, some excrete antifreeze to create liquid water microenvironments, bacteria caused the oxygen catastrophe on earth which completely changed 'earth-like' conditions).

http://www.damninteresting.com/how-bacteria-nearly-destroyed-all-life

We can find 'habitual zones' on most rocky planets or comets for many bacteria...we could probably find suitable environments on gas giants or even moons that have methane rain, lakes and oceans..depending on whether those bacteria like any of the above.

Zillah · 03-01-2011 4:18am

maninasia wrote: »

He's can't even write properly and he hasn't even read what I wrote, he's right about nothing.
I've never mentioned anything about a habitual zone, we are talking about the bogus goldilocks zone and how it is not a very useful idea and could very well be very misleading. Look at the moons around Saturn and Jupiter for example, look at what we know and don't know. Mars is in the goldilocks zone near Earth, has fairly similar chemistry and size, the main difference is that on Mars tectonic activity seems to have stopped a very long time ago. Then there is organic material in comets..that obviously could be a suitable living environment for some bacteria. It seems some people don't like they were called up on the shortcomings of a mediocre idea.

You're constantly railing against a total strawman that no one is proposing.

The Goldilocks zone simply states that we should try to look for planets with earth-like conditions to find earth-like life.

- Pointing out that there are other conditions under which liquid water and life could appear is irrelevant...no one is saying otherwise.
- Pointing out that Mars has no life despite being on the edge of the habital zone is irrelevant. No one is saying that every planet in the zone must have life.

All that they're saying is that, all things being equal, liquid water (and therefore life as we know it) is very likely to occur on the surface of an earth-like-planet within a band around a star a lot like the zone we currently inhabit. This is not necessarily the only kind of life, this is not necessarily the only place that water can occur, it's just saying that we know it is likely based on our observations of Earth.

Everything that you're railing against are unnecessary assumptions that you're making. You are causing the problem.

maninasia · 03-01-2011 4:31am

But liquid water will occur in many many different situations, that's one of my main points http://en.wikipedia.org/wiki/Europa_(moon), Plus moons outnumber planets by a factor of what in our own solar system (there are 168 moons in our solar system alone) and there is probaby more chance of life or even 'earth like life' (whatever that means) on moons than planets (moons can generate extra heat from gravitational forces aswell as tectonic activity...energy source from the sun may not be very important). Bacteria and life will generate energy from whatever available energy source is available.

You go on about Earth like life now knowing how to define it, if you define it as including the majority of life that is bacteria well then the goldilocks zone can stretch through most of the Solar System, read my last post.

In addition Mars HAD liquid water on the surface but doesn't now even though it is in the middle of the goldlilocks zone, obviously the determinants of liquid water are quite complex (not exactly very likely like you state in your post), but there could still be bacteria under it's surface, in fact I'd say it's a near certainty.

Cú Giobach · 03-01-2011 10:51am

maninasia wrote: »

But liquid water will occur in many many different situations, that's one of my main points http://en.wikipedia.org/wiki/Europa_(moon), Plus moons outnumber planets by a factor of what in our own solar system (there are 168 moons in our solar system alone) and there is probaby more chance of life or even 'earth like life' (whatever that means) on moons than planets (moons can generate extra heat from gravitational forces aswell as tectonic activity...energy source from the sun may not be very important). Bacteria and life will generate energy from whatever available energy source is available.

The whole discussion around a "goldilocks zone" is about liquid water on the surface of a body.
Its about the search for a body with certain characteristics that are simular to Earth, no other body in this solar system has any of these characteristics.
It is not about searching for life in general.
In fairness you are missing the point here.

maninasia · 03-01-2011 11:35am

I guess I have gone off a tangent a bit, I apologise if I offended some people. I just think the idea is very simplistic and the name itself is misleading, they should call it 'possibly liquid water planetary zone' not a 'just right for life zone'.
The point still stands that bacteria don't need large bodies of liquid water.

Johnmb · 03-01-2011 1:18pm

maninasia wrote: »

He's can't even write properly and he hasn't even read what I wrote, he's right about nothing.
I've never mentioned anything about a habitual zone, we are talking about the bogus goldilocks zone

Okay, right there shows just how much you don't understand. The term "Goldilocks zone" is a nickname for the concept's official name "Habitual zone". If you can't even get the terminology right the chances of you grasping an understanding are incredibly slim.

and how it is not a very useful idea and could very well be very misleading. Look at the moons around Saturn and Jupiter for example, look at what we know and don't know.

Those who would be using it actually understand it, so they would not be mislead. Moons generally are not counted even if they are in the habitual zone.

Mars is in the goldilocks zone near Earth, has fairly similar chemistry and size, the main difference is that on Mars tectonic activity seems to have stopped a very long time ago.

So? It has already been explained to you that the concept does not say, or even imply, that all planets within a habitual zone will have life.

Then there is organic material in comets..that obviously could be a suitable living environment for some bacteria. It seems some people don't like they were called up on the shortcomings of a mediocre idea.

Again, so? Earth like life on Earth like planets is what the concept deals with. Since when is a comet an Earth like planet? It would seem that your misunderstanding of basic terminology goes beyond the name of the concept you are trying to discuss.

Mars is as earth like as they come smack bang in the middle of the goldilocks zone, it's not exactly swarming with life now is it (not that there isn't life in the subsurface), there are other candidates like the moons of Saturn and Jupiter that have just as attractive chance as Earth-life life.

Already repeating yourself, despite it having nothing to do with the concept you are discussing. As for Mars, not every planet in a habitual zone will have life, the concept never suggests otherwise. As for Saturn's and Jupiter's moons, what part of "Earth like" are you not getting?

I notice how the argument starts stressing Earth-like life now..

It doesn't just start doing that now, it has always done it, from the start. That's what the concept was created for. Earth like life on an Earth like planet.

but bacteria can exist in a massive range of different environments as we well know..

Good for bacteria, the concept also never said life couldn't exist elsewhere. It doesn't make any comments on other forms of life, nor does it make comments on planets in other areas of a planetary system.

what is 'earth like conditions' per se?

Look out your window, there's an example. An Earth like planet, much like Earth, will not have uniform conditions.

Some bacteria prefer CO2 environments, some prefer O2, some break down methane, some take energy from radioactive sources and sulphur, some resist high doses of radioactivity, some can remain dormant for perhaps millions of years, some can survive long periods of vacuum, many live in colonies creating their own minienvironments, some excrete antifreeze to create liquid water microenvironments, bacteria caused the oxygen catastrophe on earth which completely changed 'earth-like' conditions).

http://www.damninteresting.com/how-b...royed-all-life

That's nice for them, but again, has nothing to do with the concept being discussed.

We can find 'habitual zones' on most rocky planets or comets for many bacteria

Actually, no you can't. See, this comes down to not understanding the terminology. Planetary habitability is a different concept. The habitual (Goldilocks) zone refers to a planets place within its planetary system, and that systems place within its galaxy (although the latter has been much less defined due to a lack of research).

...we could probably find suitable environments on gas giants or even moons that have methane rain, lakes and oceans..depending on whether those bacteria like any of the above.

We probably could, but since they are not Earth like, the concept doesn't even try to cover them.

But liquid water will occur in many many different situations, that's one of my main points http://en.wikipedia.org/wiki/Europa_(moon), Plus moons outnumber planets by a factor of what in our own solar system (there are 168 moons in our solar system alone) and there is probaby more chance of life or even 'earth like life' (whatever that means) on moons than planets (moons can generate extra heat from gravitational forces aswell as tectonic activity...energy source from the sun may not be very important). Bacteria and life will generate energy from whatever available energy source is available.

Once again, you are repeating an irrelevant point despite it already being explained to you that it is irrelevant. The Habitual zone concept never claimed that the habitual zone was the only place to find water and/or life. Nor has it ever claimed that you will find water and/or life.

You go on about Earth like life now knowing how to define it, if you define it as including the majority of life that is bacteria well then the goldilocks zone can stretch through most of the Solar System, read my last post.

Which would make it a daft concept, as it wouldn't narrow down any search areas. Also, while you may not have noticed, life on Earth, and therefore Earth like life, contains more that just bacteria.

In addition Mars HAD liquid water on the surface but doesn't now even though it is in the middle of the goldlilocks zone,

Well its not really in the middle, but regardless, you are repeating not only the same erroneous assumption, but you are using the same example, again! The concept does not say, and never has said, that all planets within the zone would have water and/or life.

obviously the determinants of liquid water are quite complex (not exactly very likely like you state in your post), but there could still be bacteria under it's surface, in fact I'd say it's a near certainty.

Good for you, (and the bacteria), but irrelevant to the Habitual Zone concept. Although, if life does/did exist on Mars and that gets proven, then the Habitual Zone concept would gain more weight as we'd then be 2 for 2 with our known samples!

I guess I have gone off a tangent a bit, I apologise if I offended some people. I just think the idea is very simplistic and the name itself is misleading, they should call it 'possibly liquid water planetary zone' not a 'just right for life zone'.

Those who are involved in the search and research understand the terminology quite well and don't get confused by it. So it is not misleading to the people who would actually be using the concept.

The point still stands that bacteria don't need large bodies of liquid water.

Once again, good for the bacteria, utterly irrelevant for the concept.

maninasia · 04-01-2011 1:55am

Yah try to be nice to people and feed them a bone and this is what happens.

Goldilocks Zone = Habitable Zone!
http://en.wikipedia.org/wiki/Habitable_zone

Seems like somebody is telling porkie pies about 'habitual zone'.

But even from this definition it is just such a ridiculous concept...habitable zone my arse!

Still not sure on the whole Earth-like life and Earth-like conditions bit...as I have explained VERY clearly Earth-like life is happy to live in the massive array of conditions found on Earth (these conditions themselves have changed enormously over billions of years and different time periods), these conditions can be replicated on different parts of moons or planets or even on comets in different zones.

The Goldilocks zone???

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