Convert Earth's Velocity (v⊕) to Cosmic Velocity - First (v₁) instantly.
About these units
Earth's Velocity (v⊕)
Earth's orbital velocity around the Sun averages about 29.78 km/s, or roughly 107,000 km/h. This enormous speed is imperceptible to us because everything on Earth—including its atmosphere—moves with the planet. Earth's velocity varies slightly over the year due to its elliptical orbit, being fastest at perihelion (closest to the Sun) and slowest at aphelion (farthest distance). This velocity influences astronomical observations, Doppler shifts in starlight, and the calibration of spacecraft navigation. Earth's motion through the Solar System is a reminder that even when we feel stationary, we are traveling at extraordinary speeds through space.
Cosmic Velocity - First (v₁)
The first cosmic velocity is the minimum horizontal speed an object must achieve to enter a stable orbit around a planetary body without additional propulsion. For Earth, this value is about 7.9 km/s. At this speed, an object's forward motion precisely balances with the gravitational pull downward, creating continuous free-fall—the essence of orbital motion. This velocity is foundational in orbital mechanics. Spacecraft reaching Low Earth Orbit (LEO) must achieve at least this horizontal speed, even if their vertical ascent profile varies. Understanding v₁ was essential in the early space age: it represented the threshold between atmospheric flight and true spaceflight, marking human entry into the orbital era.