Planetary ages (exoplanets)

[takadote26]

Long story short, in my storylines which are 'set' on different planets, characters seem much older than they are (for example I just learnt that on planet Mars a 'full year' consists of 687 days, whereas Earth only has 365 days in its rotation)- how to resolve this problem? Not to mention planet Saturn's years are even worse. Tldr; characters' ages are often very wonky because planets rotate differently around the sun- leading to a 56 year old character having the body AND stamina of a 30 year old (because Martian age)

Also, planet Mars is a totally and completely different setting to Earth because no trees and plants and also volcanoes everywhere.

 

[Madman Starryteller]

Can you have something like universal time in your stories? Based on say... Earth time? Or some other standard?

 

[Hammer]

You'll need to standardise time. Not really as drastic at it sounds - here in the UK we only used to have two times - time to go to work, and time for a beer. As we evolved we added bedtime and lunchtime. When trains could travel the whole width of the country in a couple of hours, we needed to synchronise our clocks - up until then it only mattered to mariners so that they could navigate by the stars...

Day length varies massively for different planets too - a day here on earth is, famously, 24 hours. On venus it's nearly six thousand.

You will need the equivalent of a metric hour and a metric month. We used to have Greenwich Mean Time here on Earth, but that is now called "Universal Standard Time" - you will need Universal Space Time...

 

[Homer Potvin]

What everybody else said... standardize time. That'll apply to everything, as length of day from sunrise to sunset will be different everywhere and may (or may not) be relevant. A planet with a six standard hour day for example, probably won't have normal sleep and working schedules. And there would probably be a standard GMT style clock needed for planets to talk to each other, if that's a thing.

 

[Naomasa298]

What everybody else said... standardize time. That'll apply to everything, as length of day from sunrise to sunset will be different everywhere and may (or may not) be relevant. A planet with a six standard hour day for example, probably won't have normal sleep and working schedules. And there would probably be a standard GMT style clock needed for planets to talk to each other, if that's a thing.

What he said.

Long story short, in my storylines which are 'set' on different planets, characters seem much older than they are (for example I just learnt that on planet Mars a 'full year' consists of 687 days, whereas Earth only has 365 days in its rotation)- how to resolve this problem? Not to mention planet Saturn's years are even worse. Tldr; characters' ages are often very wonky because planets rotate differently around the sun- leading to a 56 year old character having the body AND stamina of a 30 year old (because Martian age)

Also, planet Mars is a totally and completely different setting to Earth because no trees and plants and also volcanoes everywhere.

This makes no sense. Just because the time Mars takes to orbit the Sun is twice as long as that of Earth, that doesn't mean people of the same species would live twice as long on Earth that they do on Mars. If someone lives on Earth for 60 Earth years, their twin brother on Mars is going to have been alive for the same amount of time, and, ignoring gravity and all the rest of the other stuff, they will be the same physical age. That 30 year old Martian has the body of a 60 year old Earthman.

Unless time in your universe works differently.

 

[Stuart Dren]

You know, it never occurred to me that wormhole-telephoning someone on another planet might be like calling Japan from the West.

I would love it if a story played into this trope, with characters being woken up in the middle of the night, and a good number of the other conversational halves being half asleep or irate.

 

[X Equestris]

Unless your humans are integrating into a wider, established galactic community with their own standards, it makes sense to standardize the year off of Earth. T-years (Terran-years) these are called in the Honor Harrington series. In the first book, the main character references herself as “almost twenty-four years old”, but because Manticoran years are about 630 T-days long, she also notes this makes her “over forty Terran standard years”, and her biological age would likewise be in the forties if she wasn’t the recipient of medical treatments that drastically slow aging.

Hours, minutes, and seconds all make sense to leave untouched. They’d work well enough wherever you apply them. If a planet doesn’t rotate way faster or slower than Earth, you could leave the definition of day as “one full rotation” and recognize the difference between local days and “T-days”. But on somewhere like Venus, where the local day is outrageous, days would probably be set as 24 hours.