My 5 year old kid received a few National Geographic Kids books for Christmas and we have been reading them the past few days. We’ve read books about Volcano’s and Rocks and Mineral’s and I’ve been able to answer most of his questions pretty easily so far; but now we have moved on to a book about Space and the Solar System and I’m stuck on a question.
As we began the book, I mentioned that while it was currently night time where we live; it was daylight and morning in other places on Earth and referred to beach ball type of globe that I’ve been using to teach him about the world over the past few months (or mostly to throw around). He found it quite hard to believe that is could be daytime someplace, but then I showed him how the globe rotates and it that one side is opposite the sun and gets dark. I then mentioned that Earth was a planet and his reaction was pretty much: WTF? We live on a planet???
Despite having had the globe for a while I guess I never explicitly said earth was a planet; it was always just earth. Anyway this brought him to this question… Do we live in space?
My first thought was no, space is around earth. But then I said that earth floats in space and since we are on earth I think we are in sort of in space. Then my next thought was that we should ask mom… she confirmed that we live in space because it’s all around us. But he asked me again this morning and I’m hoping to get a real factual answer, if one exists. Thanks…
Bonus question… does anyone know which planet was visible yesterday morning near the moon just before sunrise in the Northeast US (1/2/2019). I thought it was Mercury, but now I think it was Venus.
Both are correct. You are using two different definitions of space. In physics, space just refers to the 3-dimensional structure of the universe. In this sense, Earth is part of space. However, in astronomy “space” refers to outer space, the region above the Earth’s atmosphere, which is close to a vacuum.
I could be wrong, but I don’t think that ‘inner space’ is a thing except as a New Agey kind of reference to consciousness.
To the OP, we do not live in ‘outer space’ or ‘space.’ We live on a planet (or maybe one could even say ‘in’ a planet.) The atmosphere of a celestial body is part of that body. If not, then Jupiter would possibly not be a planet at all (provided that its core is not solid… OK, you got me. It probably is solid way down in the depths, although maybe it’s liquid and it’s remotely possible that it’s just gas the whole way through.) Regardless, the atmosphere that we inhabit is still part of our planet as opposed to ‘space.’ Where exactly our atmosphere ends and space begins is a much more complicated question without a clear answer, but it’s safe to say that we definitely exist on the ‘planet’ side of the equation.
According to the Star Walk app, Jupiter and Venus would appear equidistant from the moon. Jupiter sunwards of the moon, Venus of the other side of the moon.
Alright thanks. Based on the answers I can see why I couldn’t come up with a definitive answer.
Excellent! Thanks!
That is good to know, I will look for one. Thank you.
Yeah, that was sort of what I was beginning to think when I started looking for an answer online. It didn’t seem as though Mercury would be very bright. What we saw was a bright light (I probably should have mentioned that…)
Thanks everyone. I don’t post a lot, but this is where i go when I need smart people.
Yeah, it’s all a matter of perspective. Some people define “outer space” as the vacuum outside of the atmosphere, (which gives rise to the idea that there should be a corresponding ‘inner space.’) But if “space” is strictly limited to vacuum, it follows that someone living on the surface of Mars or Pluto is also not “in space,” even though from our Earth-centric perspective it might seem so. (Space is the final frontier, after all)
If you take a purely objective look, the Earth is pretty obviously hanging in space and subject to the same forces as every other planet. The only thing that makes Earth fundamentally different from any other planet is that it is ‘ours.’ So if someone defined the entire solar system (or universe) as being “space,” then the answer would be, ‘Yes.’ It’s kind of screwy and perhaps a bit humbling that we talk about “The Sun” or “The Stars” as two different things, when we know perfectly well that they are not. We just treat things like “The Sun” as unique because it is ours.
Humans have a tendency, first of all, to invent categories, and second, to divide those categories based on “us” and “not us” (or at best, “like us” and “not like us”). So, for instance, we’ll divide those living things that move around on their own and eat into “animals” and “humans”, even though “humans” is a far smaller category than “animals”, and we really ought to be included in the “animals” category. Or if we’re dividing up the animals into categories, we start with “vertebrates” and “invertebrates”, even though the various kinds of invertebrates are far more unlike each other. In fact, by far the greatest diversity of life is in the prokaryotes, which we tend to lump into a single “kind”, analogous to “humans” or “birds”.
Similarly, when we’re dividing up the Universe, we have a tendency to divide it into the 0.0000000000000000000000000000000000000000000000000000000003% that is the planet we live on, and the 99.9999999999999999999999999999999999999999999999999999999997% that is everything else (apologies if I miscounted zeroes and/or nines, but I did the calculation, and those numbers are meant literally). Which says much more about how conceited humans are, than it says anything at all about the Earth’s actual significance.
It isn’t conceit as much as utility these days: Educated people know full well that the Earth is a speck orbiting a speck, but most of everything we deal with directly is inside the atmosphere of our little speck, so having a category for “inside Earth’s atmosphere” which contrasts with “outside Earth’s atmosphere” is most useful.
Earth is important because it’s the place the concept of “important” was invented, and without us, the concept doesn’t exist, and everything is equally meaningless. Therefore, nothing can be more important that Earth - unless we decide it is.
It’s semantics. Yes, we exist in ‘space’ as in a place with dimensions. When I say ‘space’ though, we generally take it to mean ‘a place outside Earth’s atmosphere.’ If I were to say to you, “A Russian billionaire just spent a great deal of money to travel to space this weekend.” You are not going to be thinking that this oligarch is traveling to Milwaukee and if that is what I meant, you would likely call me disingenuous with my statement.
I agree, this is a fairly pointless semantic issue. It’s like asking if someone living on a small island is “in the ocean”. Arguments could be made on both sides, but it just comes down to how you define “in space” or “in the ocean”. Once you make a precise definition, you have AN answer, but not necessarily THE answer, unless you can convince everyone to use your definition.
I’d say we are not in space. Furthermore, I’d say that I do not consider space to be in the atmosphere of an extraterrestrial body (of an arbitrary density, I’m not sure where that line is), nor atop a solid extraterrestrial body even if it doesn’t have a significant atmosphere. You’re only in space IMO when you’re in a near-vacuum and not in contact with a solid object with significant gravity.
