heliopause
The boundary of the heliosphere, where the
pressure at the outer part of the heliosphere equals that of the surrounding
interstellar medium (ISM). It is believed to
lie between 100 and 150 astronomical units (AU) from the Sun in the direction
in which the Sun is moving, but much further out downstream. Additionally,
the heliopause distance probably fluctuates in response to changes in ISM
and solar wind conditions. The thickness
of the heliopause is unknown but could be tens of AU.
Upstream of the heliopause, in the ISM, theory suggests the existence of
a bow shock where the incoming interstellar
wind first reacts to its impending collision with the Sun's magnetosphere.
Downstream from the Sun is thought to be a long, turbulent tail. The extent
to which interstellar matter penetrates inside the heliopause is open to
question but may be partially determined by the first interstellar
probes. Related category
SOLAR
TOPICS
Also on this site: Encyclopedia
of Alternative Energy & Sustainable Living
Encyclopedia
of History
BACK TO TOP
|