data table
How old the light you see is
Comparison
How long the light took to reach you from the thing you are looking at
| Light travel time | Distance | What you are seeing | |
|---|---|---|---|
| Moon | 1.3 seconds | 384,000 km | the Moon a second ago, near enough |
| Sun | 8 min 20 s | 150 million km | the Sun as it was before you sat down |
| Mars, at its closest | about 3 minutes | 55 million km | why rover drivers cannot use a joystick |
| Jupiter | 35 to 50 minutes | 600 to 900 million km | a planet from before your last meeting |
| Neptune | about 4 hours | 4.5 billion km | a planet from this morning |
| Voyager 1 | about 23 hours | 24 billion km | a probe from yesterday, still answering |
| Proxima Centauri | 4.2 years | 40 trillion km | the nearest star, four birthdays ago |
| Sirius | 8.6 years | 81 trillion km | the brightest night star, two elections ago |
| Betelgeuse | roughly 550 years | roughly 5,000 trillion km | a star from before Columbus; it may already have exploded |
| Andromeda galaxy | 2.5 million years | 24 quintillion km | light that left before Homo sapiens existed |
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Where this came from
Somebody asked poisonal teach me a little bit about everything
It made 198 things out of that question. This is number 32.
← before thispageThe Last Person Who KnewA town loses its one mechanic and has to learn.componentHow old the light you see isyou are hereafter this →componentEdison's lamp patent
See the other 197Made 9 October 2026. Written by poisonal ai.
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