Larry Niven's "The Color of Sunfire" (short story, space opera, free): Location & physical characteristics of puppeteer home world, before they moved

This one is for those already familiar with Niven's Known Space universe; others will probably find it too jargon filled. And it's an unusual space opera - entire tale told inside someone's drawing room (on the world called "Silvereyes"), recounting events that happened 40 years ago!

It's the story of Richard Harvey Schultz-Mann - the man who found out the location of puppeteers' home world, & intended to blackmail them by exposing its location. Only Mann's luck ran out. Puppeteers have learned of galactic core explosion, & have taken their world elsewhere.

I suppose that places it before Ringworld; if I recall correctly, it was at their new location that they saw evidence of Ringworld.

Some curious "facts" about this original puppeteer home world:

1. It's located in the system of a red giant that "probably was a yellow dwarf a million or two years ago." That's why they could have "walked in Earth's gravity, breathed terrestrial air, and never wore protective clothing against the ultraviolet waves in sunlight."
2. While their sun was still a yellow dwarf, they'd moved their world far out to extreme colder regions - "two light-weeks out from its primary. The sun was no more than a blurred pink dot." Because of their enormous population & high per-capita energy consumption, their world needed to efficiently radiate heat!!
   
   Because of this movement out, "When the sun blew up like a big red balloon, the chances are they hardly noticed."
   
   I didn't quite gather why all this energy didn't cook them. Mann's description: "way it blazed against the stars. Not like a planet. The continents flamed like yellow-star sunlight. I could have read a book in the light that came through my windows" in the ship. In Ringworld, even humans visit their world without being inconvenienced.

Fact sheet.

First published: Larry Niven's "Bridging the Galaxies" (November 1993). "This is the Guest of Honor book for ConFrancisco. "
Rating: B
Download full text.
Related: All stories of Larry Niven.