3I/ATLAS is racing through the solar system at well over 130,000 miles per hour, making it the fastest interstellar comet ever observed.

Quick scoop on its speed

  • When astronomers first measured it, 3I/ATLAS was moving at about 137,000 miles per hour (around 221,000 km/h, or 61 km/s) relative to the Sun.
  • As it fell deeper into the Sun’s gravity well, its speed increased even more, reaching roughly 68 km/s (about 152,000 mph) near closest approach to the Sun.
  • Popular explainers often round this to “about 130,000 mph” when describing how fast it is plunging through the inner solar system.

In simple terms: it’s moving tens of times faster than a typical passenger jet and significantly faster than previous interstellar visitors like 1I/ʻOumuamua and 2I/Borisov.

Context and why it’s so fast

  • 3I/ATLAS follows a strongly hyperbolic path, meaning it’s not bound to the Sun and will pass through once and head back to interstellar space.
  • Its extreme speed comes from both its original motion through the galaxy and additional gravitational “slingshots” as it fell toward the Sun.
  • It comfortably misses Earth by tens of millions of miles; there is no impact risk despite the high speed.

So if you’re asking “how fast is 3I/ATLAS moving” in the latest updates: think roughly 130,000–150,000 mph relative to the Sun, depending on exactly when along its flyby you’re talking about.

Information gathered from public forums or data available on the internet and portrayed here.