NASA’s Voyager 1 is about to become humanity’s first object to reach one light-day from Earth as it pushes ever deeper into interstellar space. That’s a mind-blowing distance of more than 26 billion km for the spacecraft launched 49 years ago. When it reaches that remarkable milestone on Wednesday, its radio signals will take precisely 24 hours travelling at the speed of light to reach Earth — in other words, one light-day.To celebrate, NASA is urging people from all corners to grab their phone or a flashlight to create a wave of golden light after sunset Tuesday.SpaceX launches 15th Starship flightSpaceX launched the 15th flight of its Starship spacecraft from Texas on Friday on a mission the company hopes will be the first round-trip rocket voyage into orbit and back to the very spot where it left Earth, a key test of Elon Musk’s bid to build a fully reusable rocket system. Plans call for Starship’s uncrewed upper-stage vessel to re-enter the atmosphere after nearly a day in orbit and return to its launch tower on Saturday.