The Known Universe Scientifically Rendered For All to See | Hacker News Reader

The Known Universe Scientifically Rendered For All to See

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Celestia (http://www.shatters.net/celestia/ ) is an interactive version of the known universe, similar to the video.

One thing I like about it is that it can show you how fast you're traveling, which really helps give a sense of scale.

It's the Total Perspective Vortex, for sure.

Thanks for the link. I've just watched a sunrise from the surface of Mercury. :)

Try Saturn, through the rings.

Though the model may be accurate, the fly-through speed is impossible to comprehend, and compromises any feeling of scale or distance. You still have to read the captions and think. Anyone know of an animation that's a little more appreciable in that regard? I imagine it's terribly boring.

Edit: (8.8e26 meters) / (mach .8) = 1.02435103e17 years to traverse the known universe in a 767. Well that doesn't help.

yes, i was thinking about the same thing. as far as i can tell, the velocity is increasing exponentially throughout the video.

an alternative would be to use a constant velocity and, once that gets boring, go back to the start and use a velocity ten times faster. that way, you'll know when the velocity increases and you'll also see what was shown earlier flash by, giving a sense of scale.

unfortunately, i don't know of a film that does that.

Its a good point, but it was done as a joint project with an art museum. From that point of view, I think it does a great job.

An inaccuracy at 4:57 to 5:00 where it shows the Moon's orbit to be circular(ish) around the Earth. If you show the Moon's orbit without the Earth it isn't a set of spirals, it's almost indistinguishable from a circle(ish) around the Sun. The size of the orbit around the Earth is so small compared with the distance to the Sun that the Moon's orbit looks like a circle with a slight wobble.

It's even convex.

http://en.wikipedia.org/wiki/Orbit_of_the_Moon#Path_of_Earth...

Moon's orbit is usually depicted around the Earth. Even if the choice is arbitrary it's also customary to claim that an object orbits the closest large mass, or more precisely the object and the large mass orbit the center of mass of the combined system. It is also customary to depict several orbital systems in a single image using multiple frames of reference, the context can usually be deduced even bay laymen.

More generally, your comment is inconsistently heliocentric. Why not pick the center of the Milky Way as the reference for orbit instead.

I'm not sure if you've simply missed my point, think my point is wrong, or actually disagree. Let me address your points.

Of course the Moon's orbit is usually shown as being around the Earth (and more generally, the Earth around the Sun, and other moons around their nearest large mass, etc.)

What I'm saying is that they have shown what might be interpreted as the paths of the planets as those beautifully rendered trails. People will interpret them as trails, and when they do so, the "trail" of the Moon is thoroughly misleading.

And I'm not being arbitrary, I'm interpreting those lines as trails, and hence your comment about using other points of reference is irrelevant. The Sun in this rendering is not shown as having such a trail, and hence the image shown is heliocentric.

And when using this sort of image for laymen, they may correctly take from it that the Moon orbits the Earth, but in my direct personal experience, they then believe that the Moon makes a loopy orbit when seen from a heliocentric point of view.

Which is wrong. Hence my comment.

The original is still the best: http://www.youtube.com/watch?v=A2cmlhfdxuY It's the Powers of 10 documentary made by Ray and Charles Eames.

In the video, it's shown that there's a cone of galaxies and quasars that we have seen and mapped. What prevents us from mapping the dark areas? Is the the light from the other stars in the Milky Way?

Layman to layman: it's light that hasn't reached us yet. Light that left alpha centuri last week wont get into the cone of visibility for another 4 years. During the period of inflation after the big bang some parts of the universe got so far away so quickly the we will never see those parts.

I think you're confusing the boundary of the visible universe (the limit after which light cannot have reached us yet) and the unmapped volume the poster is talking about, which is inside this boundary. Alpha Centauri was emitting light just fine 4 years ago so of course it can be mapped.

Too little money.

I asked an astronomer and she said that the Sloan Digital Sky Survey (http://en.wikipedia.org/wiki/Sloan_Digital_Sky_Survey) really hasn’t mapped those areas (yet). No artifact, but really white spots on our map.

largely yes. that and dust (which obscures things), and also priorities - the kinds of surveys that provide data for these kinds of map are typically hoping to increase our knowledge of cosmology / large scale structure / galaxy evolution, which means that they avoid looking at the milky way because (for the reasons given) you're going to see more nearby "clutter".

It's quite pretty, but to me still doesn't quite manage to convey the real scale of the universe. We zoom so rapidly from the solar system scale to the galaxy scale that we forget we've just gone up in scale by a factor of 10^9 or so. Then we do the same trick again in going from galaxy to universe scale.

I don't know.

What really hit home for me was the sphere of radio signals. To imagine that, from all that space we can see, that tiny little bubble is the frontier of where man is detectable.

For the rest of the universe, we are only a tiny speck of rock orbiting a very average and unremarkable star.

If it's any consolation, for anyone more than 4.5 billion light years out the rock and the star don't exist yet either.

Good point ;-)

Direct link to the video on YouTube: http://www.youtube.com/watch?v=17jymDn0W6U&hd=1

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