Solar-wind domain · dynamic boundary
Heliosphere
The moving boundary where the Sun's outflow meets interstellar space.
The heliosphere is the vast region shaped by the solar wind and the Sun's magnetic influence. Its boundary is not a rigid sphere: solar activity, direction and the surrounding interstellar medium all affect where the solar wind slows and where solar and interstellar pressures balance.
- Spatial representation
- Schematic dynamic boundary
- Visual representation
- Nested boundary guides
Reference measurements
The layers of a changing solar boundary
- Shaped by
- Solar wind
- Inner scene guide
- Termination shock · 84 AUA schematic anchor used for Explore framing, not a fixed universal distance.
- Outer scene guide
- Heliopause · 121 AUA schematic anchor; Voyager crossings differed by direction and time.
- Between the guides
- Heliosheath
- Boundary character
- Dynamic and asymmetric
- Direct crossings
- Voyager 1 and 2
Flow
The Sun fills space with moving plasma
Charged particles stream outward as the solar wind. Far from the Sun, that flow slows abruptly at the termination shock and continues through the heliosheath before reaching the heliopause.
Boundary
There is no single permanent radius
The heliopause marks pressure balance between solar and interstellar environments, but its location changes. Voyager measurements are direct crossings along two trajectories, not a complete three-dimensional outline of the boundary at every moment.
Scene representation
Two guide surfaces and directional flow
Explore renders a termination-shock guide, a heliopause guide and sparse radial particles. The shapes communicate nested regions and solar-wind direction; they do not claim a current measured global form.
Representation notes
What Explore is showing
The termination-shock and heliopause radii are stable scene anchors derived from representative Voyager-era context. They are not a claim that the real heliosphere is spherical, static or identical in every direction.
Two translucent guide surfaces and a sparse solar-wind flow layer communicate structure. Their opacity and smoothness are presentation choices, not measured plasma density.
Provenance