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By the way, 1% of the speed of light is 3000 km/s, which is "just" a hundred times the speed the Earth travels around the Sun.

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Somehow that suddenly makes the speed of light seem less fast.

Yep, go glance at the moon -- its light took over a second to reach you.

Or the screen in front of you: your computer probably retired several instructions in that time.

Energy is ~ v^2

The Earth travels at 30 km/s around the Sun.

(And the Sun at 230 km/s around the center of the Galaxy.)

>The Earth travels at 30 km/s around the Sun.

That's exactly what the parent comment just said.

I think they're pointing out that while the speed of the earth relative to the sun is 30 km/s, its speed relative to the center of the galaxy is quite a bit faster, which may be a fairer comparison to what's being discussed in the original article.

They're not even remotely comparable. Tangential speed x where r=several thousand light years results in SUBSTANTIALLY less centripetal acceleration than the same tangential speed where r=a few AU.

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