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Speed Comparison
A comparison that turns speeds from a snail up to light into white dots running around rings, so wildly different velocities can be judged side by side on one common footing.
Reading speed off a spinning dot
Every entry gets a ring, and the rate at which a white dot travels around it stands for that entry's speed. The snail's dot crawls slowly enough to follow with your eyes; as you move up the list the dot blurs, and at the top the ring reads as a smeared band rather than a moving point. Speeds your eye cannot track are rendered with motion blur on purpose, so the ordering is legible without reading a single number. The whole point is to hold velocities separated by many orders of magnitude in one frame at once.
Picking entries and changing units
Scroll the list and select an entry to see its speed along with a short note about it. A figure in meters per second rarely means much on its own, so familiar conversions come with it: kilometers per hour, and distance covered per day or per year. Jumping back and forth between a slow entry and a fast one is where the difference in ring rotation reads most clearly. It runs in a browser with nothing to install and behaves the same on a phone.
Why the rotation is compressed
Applying the true ratios to the rotation would make a snail and light impossible to show together, so the rotation is logarithmically compressed: something ten times faster spins five times faster, and something a hundred times faster spins twenty-five times faster. The ratios quoted between neighboring entries, however, are the real ones, so a comparison with the item right next to it can be read without distortion. Entries that appear to exceed light speed carry a note explaining why what is being measured is not a physical velocity.
When this one is useful
Anchor yourself on something your body knows, like walking pace or highway driving, then climb: sound, Earth's orbital motion and light space themselves out in orders of magnitude you can feel. In a lesson about the speed of light, showing the ring instead of the figure makes it far easier to explain why that particular number is special. Reading the notes attached to the apparently faster-than-light entries clears up a misconception that comes up often. Entries tied to astronomy can be followed up in the site's encyclopedia and sky news sections.
Look it up here
- How fast does light travel? Light travels at about 300,000 km per second, and radio waves and gravitational waves share that same top rung. Show it here →
- How fast does sound travel through air? Sound moves through air at about 343 metres per second, sitting nearly a million times below light on the scale. Show it here →
- How fast does the Earth move around the Sun? Earth orbits the Sun at about 29.8 km per second, landing between sound and light on the speed axis. Show it here →
- What happens if you compare by mass instead of speed? On the mass axis objects line up the same way, showing how many orders of magnitude the Sun stands apart. Show it here →
FAQ
Does the dot spin in true proportion to the speed?
Not directly. The rotation is logarithmically compressed, so ten times faster spins five times faster and a hundred times faster spins twenty-five times faster. The ratios stated between neighboring entries are the real values, so a comparison with the item next to it is accurate.
Why do some entries look faster than light?
Because nothing material or informational is actually travelling at that rate. Those entries come with a note explaining what is being measured and why it does not count as a physical velocity.
Can I see the speeds in units I actually use?
Yes. Alongside the raw figure you get familiar conversions such as kilometers per hour and the distance covered in a day or a year, which help when a value in meters per second means nothing to you.