Where does outer space begin? – The Clare People - The Clare People

Detailed chronology of events right after the Big Bang (Image : Reproduction/The Ohio State University)

Since then, it has continued to expand more and more, an expansion that lasts 11, 8 billion years. This means that you, me, the Earth, the Sun and the Milky Way are just in a space that already existed at the Big Bang, but that has expanded enough to fit all these cosmic objects that enchant us during a night clear of clouds and fog. This is why we cannot point to the direction where the Big Bang occurred. In a way, we are at the place where it happened.

It is also for these same reasons that the cosmic background radiation (the “fossil” of light left over from the Big Bang) is observed in any direction in space where we look—with large telescopes, of course. Thus, the most appropriate way to ask about the beginning of the universe is not “where” but “when”. This is also true for “where does space outside Earth begin?”, because the Earth is immersed in this space, which is the very expansion that resulted from the Big Bang.

The space where our little one The pale “dot” we call a planet already existed in the Big Bang. It makes no sense to ask where it starts, because we have no external reference to the cosmos. We are in the same universe, where the space between galaxies increases, and where energy and matter are changing all the time.

Where is the edge of the Earth’s atmosphere?

SpaceX’s Inspiration4 mission, which took civilians to space (Image: Reproduction/DrSianProctor/Twitter)

Well, if your question is where the domains of the Earth’s atmosphere end, perhaps the answer could be more objective — but it isn’t! The boundary between our atmosphere and outer space (from the English “outer space”, which literally means “outer space”) is also quite relative. It was not enough to know that the “external space” is nothing else where we are immersed, there is also no exact definition for this border.

There are some international treaties that define “space” as something free for exploration and use by all (as long as it is not used for military purposes), but this does not apply to sovereign airspace above nations, for example. Therefore, countries define their own limits and the laws that govern airspace and outer space are different. So where does a country’s airspace end and space begin? This is a political issue, and some countries, like the US, have resisted the idea of ​​delimiting borders.

It is also difficult to define these limits through the atmosphere, because it doesn’t end up “out of nowhere” , but gradually diminishes until it becomes a thin layer in space. If we take this definition literally, many satellites, and the International Space Station itself, would still be on Earth rather than in space. But things are more complicated than that.

Some experts might also say that space starts at the point where the atmosphere alone is not enough to support a spaceship at suborbital speeds. The opposite may also be true — there must be a limit where satellites can no longer orbit. If we observe the flight of all satellites with publicly available data, we realize that they can orbit the planet countless times below an altitude of approximately 80 km, but those who dipped below 100 km met a quick and fulminating end, most of the time.

I was once a child with a dream looking up to the stars. Now I’m an adult in a spaceship looking down to our beautiful Earth. To the next generation of dreamers: if we can do this, just imagine what you can do https://t.co/Wyzj0nOBgX #Unity13 @virgingalactic pic.twitter.com/03EJmKiH8V

— Richard Branson (@richardbranson) July 11, 470533

Apparently there are few atmospheric effects above 13 km of altitude. But maybe there is not much interest from companies, organizations and countries in establishing this limit. On the other hand, as space tourism becomes more and more real, the debate may be amplified. After all, if you pay a fortune to go into space, you’ll probably want to make sure you’re actually off planet Earth. a lot of confidence that our planet’s boundary with “outer space” is this or that altitude.

Source: National Geographic, Astronomy

Did you like this article?

Subscribe your email on Canaltech to receive daily updates with the latest news from the world of technology.

Adblock test (Why?)

https://news.google.com/__i/rss/rd/articles/CBMiPmh0dHBzOi8vd3d3LmNsYXJlcGVvcGxlLmNvbS80NDYyLXdoZXJlLWRvZXMtb3V0ZXItc3BhY2UtYmVnaW4v0gEA?oc=5

2021-09-26 21:10:56Z
CBMiPmh0dHBzOi8vd3d3LmNsYXJlcGVvcGxlLmNvbS80NDYyLXdoZXJlLWRvZXMtb3V0ZXItc3BhY2UtYmVnaW4v0gEA