May 25, 2012
Beyond the Heliosheath: ISM Traverse & The Local Fluff
Posted by Tom Kerwick in categories: engineering, futurism, space
It’s been a while since anyone contributed a post on space exploration here on the Lifeboat blogs, so I thought I’d contribute a few thoughts on the subject of potential hazards to interstellar travel in the future — if indeed humanity ever attempts to explore that far in space.
It is only recently that the Voyager probes provided us with some idea of the nature of the boundary of our solar system with what is commonly referred to as the local fluff, The Local Interstellar Cloud, through which we have been travelling for the past 100,000 years or so, and which we will continue to travel through for another 10,000 or 20,000 years yet. The cloud has a temperate of about 6000°C — albeit very tenuous.
We are protected by the effects of the local fluff by the solar wind and the sun’s magnetic field, the front between the two just beyond the termination shock where the solar wind slows to subsonic velocities. Here, in the heliosheath, the solar wind becomes turbulent by its interaction with the interstellar medium, and keeping the interstellar medium at bay from the inners of the solar system, the region currently under study by the Voyager 1 and Voyager 2 space probes. It has been hypothesised that there may be a hydrogen wall further out between the bow shock and the heliopause composed of ISM interacting with the edge of the heliosphere, another obstacle to consider with interstellar travel.
The short end of the stick is that what many consider ‘open space’ to traverse once we get beyond the Kuiper belt may in fact be many more mission-threatening obstacles to traverse to reach beyond our solar system. Opinions welcome. I am not an expert on this.