Earth to the Moon, at real speed.
A beam of light crosses the 384,400 km to the Moon in about 1.3 seconds, bouncing back and forth below in real, unsped-up time. Every slower traveller — a solar probe, a bullet, even sound — barely inches forward at this scale, so the first 5,000 km is magnified underneath instead.
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Total distance light has crossed
km
Total path travelled, not current position.
Distance is the Moon's average distance from Earth; light speed is 299,792 km/s in vacuum, giving t = d/v = 384,400 km ÷ 299,792 km/s = 1.28 s one-way. The lower ruler isn't a second trip — it's the same first 5,000 km, magnified about 67× so the slower travellers become visible at all; Parker Solar Probe is the only one fast enough to see creeping even at full scale, drawn as a faint line beside light's. The speed control multiplies every clock equally; nothing is warped relative to anything else.
Speeds and sources: Parker Solar Probe's 192.2 km/s is its record closest-approach speed near the Sun (NASA), not a speed it reaches near Earth — used here as our fastest machine, hypothetically let loose on this trip. The rifle bullet's 1 km/s is a typical muzzle velocity (Wikipedia); the jet airliner's 0.25 km/s (900 km/h) a widebody's typical cruise speed (Boeing 747-8). Speed of sound: 343 m/s in air (NASA Glenn), 1,481 m/s in fresh water (The Engineering ToolBox) — water genuinely beats a rifle bullet. The distance-crossed comparison below uses Mars, Jupiter, and Saturn's average distance from the Sun, not Earth (228, 778, and 1,432 million km, NASA Planetary Fact Sheet), as a benchmark for the size of the number, not a claim about where light is actually headed.
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