Cosmic Velocity - Third to Centimeter per Hour

The third cosmic velocity is approximately 16,700 m/s (16.7 km/s), the minimum speed to escape the Sun's gravity from Earth's orbital position.

v₃ = √(v_sun² - v_Earth²) where v_sun is solar escape velocity from Earth's orbit. Approximately 16.7 km/s relative to Earth.

To km/h: × 3,600. To mph: × 37,282. 16.7 km/s = 60,120 km/h = 37,344 mph.

Voyager missions, future interstellar probes, and calculations for leaving the solar system.

Voyager 1: ~17 km/s relative to Sun (achieved via Jupiter gravity assist). Parker Solar Probe: 163 km/s peak (but toward Sun, not away).

Thinking Voyager was launched at 16.7 km/s — it used gravity assists. Also, confusing with speed needed to escape from Sun's surface (618 km/s).

~17 km/s to leave the solar system from Earth's orbit. Voyagers achieved this with gravity assists from planets.

Centimeter per hour measures very slow movements in centimeters over an hour. Used for extremely gradual processes.

1 cm/h = 0.01 m/h = 0.00001 km/h = 0.00000278 m/s. Extremely small speed unit.

To m/s: ÷ 360,000. To m/h: × 0.01. To mm/h: × 10.

Very slow geological processes, material expansion/contraction measurements, and some biological growth studies.

Human nail growth: ~0.01 cm/h. Stalagmite formation: ~0.001 cm/h. Some coral growth: 0.1 cm/h.

Using for anything except very slow processes. Confusing with cm/min or cm/s.

100 cm/h = 1 m/h. Primarily a scientific measurement unit. Not for everyday use.