The Voyager Twins are one of humanity’s greatest accomplishments in space exploration. Launched in 1977, they have both passed the heliosphere and now are exploring interstellar space, a place where no person has ever been. Voyager 1 has consistently raised the bar for being the furthest traveling human-made object and based on Nasa’s projections, it is now less than a year away from being one light-day from Earth. So, what does that mean? (Picture: Space Frontiers/Archive Photos/Getty Images)
What is a light day?
Although it uses the term day, a light day is actually a unit of distance. In our current understanding of the universe, nothing moves faster than the speed of light in a vacuum, which travels at 186,000 miles per second. This equals about 5.88 trillion miles every Julian calendar year (365.25 days). The nearest star to us, Proxima Centauri, is 4.2 light-years away — meaning if something traveled at the speed of light, it would still take more than four years to cover the distance between us. (Picture: Keystone/Getty Images)
Voyager 1 doesn’t travel anywhere near the speed of light – it has traveled at around 11 miles per second for decades, adding another 3.5 AU (the distance between the Earth and Sun) to its total mileage every single year. And the further it goes, the longer it takes to communicate with. Last year, it took weeks to sort through Voyager 1’s technical difficulties, as each command relay needed a little over 23 hours to travel the billions of miles at lightspeed from Voyager 1 to Nasa and back. (Picture: Corbis via Getty Images)
So how far is Voyager 1?
Right now it takes 23 hours, 29 minutes, and 27 seconds for signals from Earth to reach the spacecraft. When Voyager does reach 25.9 billion kilometers (16 billion miles) from Earth, it will officially be one light year away. According to Nasa, this milestone will be achieved on November 13, 2026. Then it will not fall within 24 light-hours from Earth again, despite the Earth-to-Voyager distance changing as we orbit the Sun. (Picture: Nasa/Hulton Archive/Getty Images)
Then Voyager 1 will be on its merry way, guided by Nasa, until it runs out of power – which is expected to happen in the early 2030s. However, before it does that it will leave the Solar System, passing through the Oort Cloud (known as the Solar System’s outermost frontier), and having at least one close encounter with another star, Gliese 445. (Picture: Nasa/Hulton Archive/Getty Images)
Nasa says: ‘It will take about 300 years for Voyager 1 to reach the inner edge of the Oort Cloud and possibly about 30,000 years to fly beyond it.’ If it manages to get through the cloud unscathed, Voyager will be drifting by itself for a long time, far from sources of heat and light. In 40,000 years, it will get a brief close encounter with another star, coming closer to it than home. (Picture: QAI Publishing/Universal Images Group via Getty Images)
Nasa said: ‘It took 35 years to reach interstellar space, but it will take 40,000 years for Voyager 1 to be closer to the star AC +79 3888 than our Sun. Alpha Centauri is the closest star to our own right now, but because stars are moving, Voyager 1 will actually get within 1.7 light years of AC +79 3888 (aka Gliese 445) in 40,000 years.’ (Picture: Space Frontiers/Archive Photos/Getty Images)Add as preferred source