Being a bit of a telly nerd, I do love to read up on what the showrunners are thinking for the next series - if you don't want any idea at all, don't keep reading this post.
So this is an interview with the showrunner: www.eonline.com/uk/news/958413/what-s-next-after-the-100-season-5-finale-just-blew-everything-up
This is what he says about the new planet: ""It's an Earth-like planet, we've seen it from space. It will pack many, many surprises, the creatures that we encounter are not things that would've been on Earth. You know, the threats and the mysteries, it's just endless, you know, the sky's literally the limit as far as what we can and hopefully will encounter. You know, it's survivable to humans, so it has to have a certain...as Monty says it's in the Goldilocks zone of binary star system. So we know there's two stars, we know there's water and land and trees based on what we've seen from space. The rest is going to be revealed, obviously, as they touch down in season six."
And on the passing of 125 years:
"It's ironic that even though it's a way, way longer time jump, for them it was like going to bed the night before and waking up the next day," Rothenberg says. "So you know, all of the stuff that lingers at the end of season 5 between Bellamy and Octavia, for instance, is still there in a big way in season 6 as we start. That is a relationship that is in trouble and needs to, you know, find a new normal."
And from here: ew.com/tv/2018/08/07/the-100-season-5-finale-postmortem-new-planet-monty/
"But we are going in search of Eligius III, with the hope that Eligius III made it to this planet and populated it and were able to survive. We’ll join what is essentially the next outpost for humanity. The story for season 6 is in many ways about what happened to Eligius III and how we interact with what happened to Eligius III. Are there survivors? " [There so are going to be other survivors, aren't there?]
And this reddit thread has some supergeeks on it: www.reddit.com/r/The100/comments/95jnxd/morning_after_analysis_s5e13_damoclespart_two/
The most interesting point to me being that Eligius III were all nightbloods, so whether that means Clarke and Madi are special somehow.