The video begins with an introduction to 'Oumuamua, the interstellar object that puzzled scientists.

• 'Oumuamua is a comet-like object from another star system that showed unusual acceleration without a visible tail.
• Initial theories ranged from natural explanations to it being an extraterrestrial probe.
• A more accepted theory suggests it is a hydrogen-rich ancient comet, formed far from any star.

The discovery of six dark comets in the solar system resembling 'Oumuamua is highlighted.

• Researchers found six objects with similar mysterious traits as 'Oumuamua within our solar system.
• These objects show unexplained orbital changes hinting at outgassing that is difficult to detect.
• A future mission to one of these objects could provide more insights into their nature.

The video discusses the blurred lines between comets and asteroids and recent findings on active asteroids.

• The video explains that the distinction between comets and asteroids is not clear-cut.
• Active asteroids, like asteroid Bennu, show cometary traits, blurring the line further.
• The phenomena of outgassing and the Yarkovsky effect are explored in relation to these objects.

The video returns to 'Oumuamua's strange behavior and introduces a new scientific theory explaining it.

• 'Oumuamua's deceleration remains unexplained by traditional comet behavior, as no tail or outgassing was observed.
• New research suggests 'Oumuamua and similar objects may exhibit outgassing that's hard to detect, possibly from water sublimation.
• This theory could explain the non-typical acceleration and surface features of these objects.

Upcoming missions and observations that may shed light on dark comets and 'Oumuamua are discussed.

• Hayabusa 2 mission is planned to visit one of the dark comets in the early 2030s.
• James Webb Space Telescope might observe one of these objects in 2024, potentially confirming or refuting the dark comet hypothesis.