Description |
Runaway OB stars are massive early-type stars that travel through interstellar space with an anomalously high velocity. As the star travels with supersonic velocity through the interstellar medium matter is swept up resulting in a bow shock. The exact shape and conditions (density, temperature) of such a bow shock region depend critically on the stellar properties (such as velocity and mass-loss rate) as well as on the properties of the surrounding interstellar medium. Beyond the physics of the bow shocks themselves the size and shape can be used to infer parameters of the stellar wind of the star as wel as the local interstellar medium. We propose to use both the PACS and SPIRE instruments in photometric mode to charaterise in detail the far-infrared spatial structure and corresponding spectral energy distribution of these bow shocks. In particular, we expect to resolve, if present, turbulent instabilities. |