Why Does NASA Think There Are 1,000,000,000,000 Starless Planets in Our Galaxy?

The video explores rogue planets, which are planetary-sized objects not bound to stars. It discusses their possible origins and the challenges in detecting them due to their lack of light emission. The video introduces gravitational microlensing as a technique to detect these planets, explaining how it works and its advantages over other methods. The role of the upcoming Nancy Grace Roman Space Telescope in enhancing detection capabilities is highlighted. Current discoveries and future prospects in rogue planet research are also discussed.

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