regram @curiositydotcom
#Neptune completed its first full #orbit around the #sun since its discovery on July 12, 2011. NASA’s #Hubble #Space #Telescope took photos of the #planet to commemorate the occasion, timing the snapshots so that they captured all of Neptune’s sides during its 16-hour rotation. When Neptune was discovered in 1846, it doubled the size of the known #solar #system, creating a boundary at 2.8 billion miles (4.5 billion kilometers) from the sun. Its seasons last the longest of any planet’s in the solar system, and are a stark counterpoint to Mercury’s, which shift so quickly that it’s impossible to determine when one ends and another begins. #planets #solarsystem #outerspace #astronomy #NASA by astroclubbhs