Launched in 1977, Voyager just reached one light-day away

Voyager 1 will cross one light-day from Earth on November 18 at 5:16:07 a.m. Eastern time, reaching 16.094 billion miles from the planet it left in 1977. That is how far light travels in 24 hours. Sunlight, by comparison, reaches us in about eight minutes. The milestone is purely symbolic. Nothing happens to the spacecraft when it passes the mark. But getting it there has meant decades of improvising. The probe launched with ten working instruments and now runs on two, its decaying plutonium power supply dropping by several watts a year. Scientists expect the signal to fade past hearing around 2035. "If you want to say 'hello' to Voyager, you send your message, and then you go home, and you wait two days before you finally get a response," said Suzanne Dodd, Voyager project manager at NASA's Jet Propulsion Laboratory. To mark the crossing, NASA is asking people to flash the Morse code for V-G-R into the sky after sunset on November 17.