Long time to travel 100D from THIS star!

[phavoc]

Dunno if anyone does much with the 100D limitation, but astronomers have gotten some new measurements on what they are calling the largest star ever discovered (and they think it could be even bigger). It's a super red giant in the Milky Way. If it were in our solar system it's radius would take it beyond the asteroid belt (possibly even out to Saturn's orbit). The inner system would be totally engulfed and there is some supposition that the remaining outer planets might be gone as well due to the orbital changes from it's expansion. That might make Pluto a marginally habitable world (with a tainted atmosphere), though mysterious planet X could actually get some weather patterns, maybe like Mars does today.

Just for giggles, it's 21 Billion times the volume of Sol

https://www.yahoo.com/tech/everything-know-uy-scuti-largest-201544542.html

 

[mancerbear]

That's a big gravity well

 

[hivemindx]

There was a video that showed star sizes a few years ago. I found the creator has an updated version which includes the star under discussion here. The music on the old version is better though.

https://youtu.be/GoW8Tf7hTGA

 

[Reynard]

Only reason to go there is as a jump point to another system. Seriously doubt there's much else the star had not assimilated. Might be a tourist attraction.

 

[Condottiere]

Arcturus (/ɑːrkˈtjʊərəs/), also designated Alpha Boötis (α Boötis, abbreviated Alpha Boo, α Boo) , is the brightest star in the constellation of Boötes, the fourth-brightest in the night sky, and the brightest in the northern celestial hemisphere. Together with Spica and Denebola (or Regulus, depending on the source), Arcturus is part of the Spring Triangle asterism and, by extension, also of the Great Diamond along with the star Cor Caroli.
Relatively close at 36.7 light-years from the Sun, Arcturus is a red giant of spectral type K0III—an ageing star around 7.1 billion years old that has used up its core hydrogen and moved off the main sequence. It is 1.08 ± 0.06 times as massive as the Sun, but has expanded to 25.4 ± 0.2 times its diameter and is around 170 times as luminous.

We should have a couple of adventures occurring in these star systems.

How extensive would be the Goldilocks zone?

 

[phavoc]

The size of Antares is about 7AU (about mid-way between Mars and Jupiter's orbit) Conversely UY Scuti's radius is about 18AU (Saturn's orbit).

Looking at a solar system map you can compare relative sizes. It's a good question about the Goldilocks zone.

 

[Condottiere]

You could artificially increase the number of planets; the protagonists may never need to leave the system.

 

[JMISBEST]

How could anyone increase the number of inhabitable worlds?, sounds impossible even for the ancients, or do you mean artificial/man-made worlds?

 

[locarno24]

As in; declare the number of worlds to be appropriate for a 700 AU 100d System.

It doesn't really work, because so far as we know, the system would have been scaled to the (un expanded) scale of the star, which means it would almost inevitably have consumed the bulk of its system.

As noted, it could still have gas giants with moon systems which are now inside the goldilocks zone. The brighter the star, the bigger the goldilocks zone (albeit further from the star), so theoretically there could be several gas giants now in the zone. The question is, would that many gas giants not have more likely accreted into one big gas giant (or even brown dwarf).

If there are a load of gas giant moons with liquid water around the same (large) gas giant, you could have a huge amount of useable real estate, all at a very useful close distance to one another. Getting anywhere else would be very long-winded (because you might need weeks under conventional drive to reach a safe jump distance), but the sheer size of the cumulative settleable space could be very much worth it. Likely to produce a more insular culture, though.

 

[phavoc]

How could anyone increase the number of inhabitable worlds?, sounds impossible even for the ancients, or do you mean artificial/man-made worlds?

Nature might do it for you. Planets on the outer edge of the system (like Pluto today) are frozen rocks. Scale up the star - and keep the radiation output, heat, etc - to a livable level and all of a sudden those outer frozen rocks might thaw and develop biospheres of their own.

Could be that you had a tidally-locked Sol-sized moon orbiting a gas giant. The gas giant blocks a lot of the immediate radiation and heat and such from the star, but enough gets around the edges to provide enough to bring that moon within habitable standards. With so many planets out there it's possible this combination already exists. And in a game setting pretty much everything is possible. All it takes is a Ref with an adventure plan