Jashari was a planet in the same solar system Simia orbited.
It is a large grey planet with a climate similar to Earth
Not many Lifeforms know what happened to Jashari and so there are different theories. These being as diverse as the Primate coming and moving Simia into another galaxy or a rift in time. The most excepted of these theories are that the star,known in the galaxy as Jasaro had a supernova explosion and destroyed it or that the planet Xervus crashed into it.
Accounts of space pirate accounts found on Simia state that Jashari was a steampunk industrial planet. It had steam trains and lots of railways with floating houses and machines. Laser guns had been invented and hovercraft too, although, the hovercraft were oddly never used.