Eshems Nebula

The Eshems Nebula is a location from the Movie and Animated continuity families

Not much is known about Eshems Nebula except that it located several lightyears from Cybertron and could be home to aliens who want to possess the AllSpark.

Fiction

IDW Transformers movie comics

Starscream ran afoul of an alien scout ship in the Nebula and presumably destroyed it, noting that it was the fourth spotted in that area. Shortly after, green-skinned aliens massed a fleet in the nebula and took off for Cybertron. Their objective: the AllSpark. Defiance #1

After the devastating alien attack, Megatron lead a Cybertronian force back to the nebula and attacked the alien fleet. After killing the captain of the alien flagship personally, Megatron ordered Starscream that there were be no survivors. Defiance #2

Much later, after war the war between Autobot and Decepticon had raged for eons, Optimus Prime launched the AllSpark into space to keep it from Megatron's clutches. Megatron pursued it into the Eshems Nebula and beyond. The Reign of Starscream #1

Transformers Animated

Blackarachnia describes the sensor array that she installed on the Nemesis as the most sophisticated "this side of the Eshems Nebula." The AllSpark Almanac