They discovered that these peculiar shapes form when planes fly through "altocumulus clouds." Researchers at the University Corporation for Atmospheric Research (UCAR) have unlocked the secrets ...

Because of their rarity and unusual appearance, fallstreak holes, or punch hole clouds, are often attributed to UFOs because they form as large circular gaps in cirrocumulus or altocumulus clouds.

or a series of lenticular clouds, is capable of forming. These are often mistaken for UFOs because of the saucer-like shape. They can separate into altocumulus standing lenticular, stratocumulus ...