
Visualize the orbits of exoplanets - gkst
https://nbremer.github.io/exoplanets/
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typpo
Really like this. We're discovering new exoplanets so quickly. Wanted to share
a similar webgl visualization I made, with colors that indicate the
temperature range/habitability of the planet rather than spectral class:

[http://www.asterank.com/exoplanets](http://www.asterank.com/exoplanets)

Here's the source code:
[https://github.com/typpo/asterank/blob/master/static/js/3d/k...](https://github.com/typpo/asterank/blob/master/static/js/3d/kepler3d.js)

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tgb
Very nice one! Not all the planets are orbiting in the same plane. Is that
stylistic choice or does it reflect some factor?

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typpo
It reflects the inclination of the exoplanets' orbits around their parent
stars. We can actually measure this based on the light curve of a star as a
planet passes in front of it.

Here's a quick explanation of how that's done:
[https://www.paulanthonywilson.com/exoplanets/exoplanet-
detec...](https://www.paulanthonywilson.com/exoplanets/exoplanet-detection-
techniques/the-exoplanet-transit-method/)

~~~
tgb
Nice article, thanks. So this inclination is a measure of an offset of the
plane of the exoplanet's orbit from the line passing through Earth and the
star? So the reason most of these planets have very low inclination is A)
those are easiest to detect since they block the sun the most, in particular
we couldn't detect a planet with 90 degree inclination at all, and B) there's
a symmetry involved so there are more ways to have 0 inclination than one
might first guess (eg: take the picture in the article are rotated in the
screen, it keeps the same angle of inclination).

Part (B) is kind of fun, now that I'm thinking about it. It's saying that the
average angle between two randomly chosen planes is greater than the average
angle between a randomly chosen plane and a randomly chosen vector. To see
this, we can fix a plane, the X-Y plane and always rotate the system to use
that as the (first) randomly chosen plane. Then there's one plane of 0 degree
separation from the XY plane, namely itself, but a whole circle's worth of
planes perpendicular to it (any plane with it's normal vector lying on the XY
plane). In the opposite manner, we see that there's a single line
perpendicular to the XY-plane but a circle's worth of lines of inclination 0.
This isn't the most intuitive thing in the world, and I second-guessed myself
after I wrote (B) down.

(Actually, I guess it's a real projective line's worth, not a circle's worth,
of lines of inclination 0 (directions in a plane choose a line but two
directions choose the same line so we've doubled counted lines).)

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martgnz
Another amazing piece on exoplanets is Jonathan Corum's graphic on The New
York Times: [http://www.nytimes.com/interactive/science/space/keplers-
tal...](http://www.nytimes.com/interactive/science/space/keplers-tally-of-
planets.html)

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philipov
I am using Chrome. All the planets with orbits longer than 20-60 days are
outside the default zoom level. To see them, it's necessary to alt-scrollwheel
to zoom out, reducing the UI size to unreadible, find one of the planets at
pixel-size, mouse over it to create a tooltip, zoom back in, and then use the
scroll bar to scroll back to the tooltip. Maybe it would be better to just
make the entire field scrollable without using stupid tricks?

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tensafefrogs
Here's a different version with source code, not sure if it's the same
planets:

[http://blog.blprnt.com/blog/blprnt/data-in-an-alien-
context-...](http://blog.blprnt.com/blog/blprnt/data-in-an-alien-context-
kepler-visualization-source-code)

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tgb
Everyone should hit the "Introduction" button on the left if they haven't. It
gives a lot more context to the visualization.

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alfonsodev
it reminds me to "Make your solar system" Android video game.
[https://play.google.com/store/apps/details?id=com.JavierGome...](https://play.google.com/store/apps/details?id=com.JavierGomezPereda.MakeYourSolarSystem)
People who likes this post may enjoy MYSS game too.

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aswanson
Gravity is such a simple but strange aspect of the physical universe.

