Once considered the ninth planet, Pluto now wanders the Kuiper Belt as a ghostly reminder of our evolving understanding of the solar system
This hypothetical planet has captured the imagination of doomsday enthusiasts, but its existence remains a mystery
This hypothetical planet was once thought to exist between Mercury and the Sun, but its existence was later debunked
This ancient planet is believed to have been destroyed, leaving behind the asteroid belt as a ghostly reminder
This hypothetical planet is thought to exist in the outer reaches of the solar system, but its existence remains unconfirmed
This hypothetical star is believed to be responsible for periodic mass extinctions on Earth, but its existence remains a mystery
This recently discovered planet lurks in the outer reaches of the solar system, its presence felt but not seen
This ancient moon is believed to have collided with Earth, leaving behind the Moon as a ghostly reminder.