A planet in the Dholen system of the Far Rim.

  • Orbital Distance: 6.3 AU
  • Orbital Period: 15.8 Earth Years
  • Radius: 6,721 km
  • Day Length: 18.5 Earth Hours
  • Atmospheric Pressure: 0.0 Earth Atmospheres
  • Surface Temperature: 44 Celsius
  • Surface Gravity: 1.2 G

Because Haestrom’s sun has overwhelmed the planet’s protective magnetosphere, humans foolhardy enough to venture onto it must exercise extreme caution. Minutes of radiation exposure will overload shields and hours of exposure will kill. Furthermore, solar output renders surface-to-orbit communication nearly impossible.


Haestrom was colonized by quarians who intended to study the mysterious instability of its sun, which threatened premature eruption into a red giant. As a scientific outpost of minimal military value, Haestrom was ill-equipped to repel geth forces and fell quickly under their control during the Morning War. Soon after, all communication from the planet and its attendant space stations ceased.

The geth showed no signs of treating Dholen as a threat over the next three centuries, other than establishing several space stations near to it. Dholen’s magnetic eruptions and solar output overwhelm most communications, and it was unclear how the geth had compensated.

Spy probe scans indicated extensive orbital construction around Haestrom, housing thousands of geth platforms and an unknown number of geth software “minds”. It wasn’t known how many geth were on the planet’s surface: Spy probes faced interference from Dholen, making remote scanning difficult. Resource estimates based on geth mining, refining, and fabricating procedures suggested that the planet had at least 20 more years of use before it was exhausted. Intelligence experts speculated that the geth hadn’t exploited all their resources because they wished to keep some in reserve for repairs.

The Battle for Haestrom

Following the Reaper War, Haestrom falls under the control of the quarian-geth alliance. The quarians themselves have shown little interest in seeing Haestrom recolonized, and it's unlikely that efforts would even be able to begin before Haestrom is totally exhausted by the geth. The current population is 500,000 geth platforms, 543 quarians. These quarian research teams are studying the colony itself as part of the ongoing cultural rediscovery project, though some science teams have expressed interest in using the planet as a platform to study the rapidly decaying star Dholen.