Smith Cloud

The Smith Cloud (or Smith's Cloud or Lockman Cloud) is a high-velocity cloud within the galactic halo of the Milky Way that apparently will collide with the Milky Way disk in 30 million years. It shows a comet-like tail.

• 12.4 kpc - distance.
• 100 km/s - approximate velocity relative to local standard of rest.
• 3 kpc × 1 kpc - size.
• 2×10⁶ solar masses.

Its trajectory to collide with the Milky Way disk gives credence to the notion that some star formation arises from such collisions.