British astronomer William Lassell discovered Neptune’s largest moon, Triton.
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Alvan Graham Clark discovered the white dwarf star Sirius B.
NASA revealed that water vapor was discovered in the atmosphere of an Earth-size planet, the exoplanet K2-18b.
Three Russian cosmonauts returned from space after spending a record time of 237 days in orbit.
Dutch astronomer Johannes Fabricius discovered sunspots.
Asteroid 323 Brucia became the first asteroid discovered using photography.
