Voyager – A 70s child
Remarkably the Voyager 1 probe is still functioning despite being launched in 1974 and crossing an unfathomably large distance at an incomprehensible speed. It’s the farthest human made object from Earth and has always fascinated me. It currently sits somewhere around 19 billion kilometers away, having left our solar system a few years back. The radioactive batteries that power it are gradually fading which means only a few of it’s instruments are still working. Still though, it continues to send information back to earth at a steady rate of 160 bits per second from outside our solar system; it’s incredible that the signal can still be picked up from such a remote place.
A long way from home
One of my favourite facts about Voyager is that despite it traveling at such a crazy speed, it’s not going to encounter any other stars for a pretty long time… in around 40,000 years it’ll pass near a star called Giliese 445. Because space is such an empty place it’s likely to arrive there in pretty much the same condition it is today, a mysterious relic from a culture which will have undoubtedly changed beyond recognition if it still exists at all. By the time it gets there, the timeline of the far future tells us we’ll almost be in the next ice age and that humanity will likely be extinct, on the plus side we’ll only be 10,000 years away from all CFCs being broken down.
Everything that glitters
The team of scientists headed up by Carl Sagan knew that an object like Voyager was likely to exist for an incredibly long time, almost certainly longer than humanity, they therefore attached the ultimate time capsule. Strapped to the side of Voyager is an LP style record containing the sounds of earth. Gold’s inertness made it the material of choice. It features a whole load of classical music as well as tracks like Johnny B. Goode by Chuck Berry, there’s also engraved instructions on how to make a turntable to play it. Sagan wanted to include a copy of ‘Here comes the Sun’ by The Beatles but although they were keen, their record label objected. Perhaps they feared interstellar piracy might make a dent to their quarterly profits, it seems like an utterly bizarre decision.
The other items that are etched on are fascinating, they clearly had to be drawn in a way which would allow for any sentient life form that finds it to interpret them without language. Some of the items that made the cut included an anatomical drawing of the human species, the depiction of a hydrogen atom and a map of our solar system. To have worked on these designs must’ve been a uniquely strange experience, knowing that one day the eyes that try to decode these drawings may belong to a altogether different intelligent life form in an altogether different part of the galaxy.
I’m a particularly big fan of a website called ‘What If’, it’s a website that answers qabsurd questions using science. Things like, ‘What would happen if a pitched a baseball at 90% the speed of light?’ or ‘If I put a hole at the bottom of the Marriana Trench, how long would it take to drain the oceans?‘. I love this site and genuinely look forward to new posts, I’d definitely recommend checking it out. One of the posts from a while back mentioned the Voyager spacecraft, the question was ‘How long would it take to go and fetch the voyager probe if we wanted to?‘ The answer is pretty interesting. It turns out that due to the amount of jet fuel you’d need to carry to accelerate to the necessary speed to catch up and overtake it is huge. It’s not that surprising considering it has a 40 year head start, you’d then need to decelerate (when changing direction) and then re accelerate, in total you’re looking at hundreds of tonnes of fuel! Still, to get the rarest copy of Johnny B. Goode in existence perhaps it’s not out of the question.
End of the road
So what will the final fate of the Voyager probe be? We know that it doesn’t have the escape velocity needed to leave the Galaxy which means it’ll likely makes its way round the galaxy over the next few billion years. The vast tracts of nothingness of space make it almost impossibly unlikely that it’ll hit anything. When the Andromeda Galaxy collides with the Milky way in around 4 billion years, there’s an almost 0% chance of any of the 100 billion or so stars in each galaxy hitting any others so a tiny probe from Earth hitting anything is unfathomably less likely. Maybe at that point Voyager will get flung out of the two colliding galaxies and spend the rest of the life of the universe drifting through deepest, darkest intergalactic space – the carrier of the some of the last vestiges of humanity. Or maybe the Golden record will get picked up by an alien civilization millions of years from now, maybe they’ll follow the instructions to create the record player it depicts and play music written by our long since dead classical greats. It seems a somewhat missed opportunity that but for EMI records, at that point we’d have finally established whether the love of the Beatles is truly universal.