Europe’s Planck spacecraft found evidence that our universe is 13.8 billion years old.
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Gliese 229B became the first brown dwarf to be seen and identified by astronomers.
STS 77 (Endeavour 11) was launched into orbit.
After 14 years in space, NASA's Galileo spacecraft was intentionally destroyed in Jupiter's atmosphere.
NASA's Ingenuity helicopter became the first helicopter to fly on another planet.
North Korea launched the infamous Kwangmyŏngsŏng-2 satellite.