For millennia, humanity was grounded on Earth, only able to study the vastness of the Universe with our eyes. However in the 20th Century, we made our first forays into the depths of space, finally reaching above the thin atmosphere at the Garmin line. We progressed to placing satellites and humans into orbit above the planet, then to making bootprints on the Moon from 1969 through 1972 with the Apollo Missions. Since those historic ventures, the nations of Earth have sent probes to study all the planets of the solar system, many of their moons, the Sun as well as asteroids, comets, and dwarf planets. We have even managed to send twin spacecraft beyond the heliopause and into interstellar space.

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