During sunset on May 26th, three planets formed a bright cluster in the western sky known as a Dance of the Planets. The celestial show peaked on Sunday when the trio appeared as a bright triangle of light in the western sky beginning about 30 minutes after sunset
The planetary trio – Jupiter, Venus, Mercury, the brightest planets visible from Earth – has been an awesome sight in the west after sunset. Triple conjunctions of planets are fairly rare. The last time it happened was on May 9, 2011, and it won’t happen again until October 17 2015. On Sunday May 26, the triangle of Venus, Jupiter and Mercury were most compact, closer than you’ll see them again until 2021. In these photographs overlooking Kailua-Kona, Hawaii, taken from my lanai, at the bottom of the triangle Venus is seen, Jupiter above that on the left and Mercury to the top right.
When multiple worlds appear to align in the sky, it’s called a conjunction. But their apparent proximity to each other is an optical illusion—in reality, Mercury is 105 million miles from Earth, Venus is more than 150 million miles away, and Jupiter is a chilling 565 million miles away.
While you ponder those distances think about this, the three planets are also joined by Earth launched orbiting spacecraft. NASA’s Juno spacecraft is on a long looping trajectory to Jupiter, the ESA’s Venus Express is orbiting Venus and NASA’s MESSENGER is orbiting Mercury.