There is a field in physics known as cosmic rays which is mostly neglected
but yet very interesting. It talks about the Sun and its influence spheres.
It follows under the branch of Space science.
According to world re-known researchers in this field like Parker, the Sun
is constantly blowing away a stream of charged particles known as the solar
wind. These particles pass through our mother Earth at very high speed-
scientists have able to measure their density and characteristic using
their wit. We are so lucky that we are protected from these particles by
the Earth’s magnetic field. However, science is so broad in a way that some
scientist can argue persistently with good reasoning and logic that the
Earth has no the magnetic field. Anyway that is the richness of science.
Scientist over the years have been debating and trying to understand the
structure of the solar wind and the magnetic field of the Sun. There is a
consensus that the solar wind undergoes a transition at very large distance
from the Sun from supersonic speeds (more than the speed of sound in the
medium) to subsonic speeds(less than the speed of sound in the medium).
This region where this transition takes place is known as the termination
shock. Its structure and geometry is not well understood and is still an
active field of research.
With this prediction made long time ago that there exist the termination
shock at large radial distances from the Sun, space probes were sent to the
outer boundary of our solar system in 1977 and they were called Voyager 1
and Voyager 2. Voyager 1 sent evidence that it has seen and crossed this
boundary in 14 December 2005, while Voyager 2 is yet to cross this
boundary. In the North-West University (Potchefstroom campus) I do research
in the transition of the solar when at the termination shock. What is
interesting is that how did scientists predicted the existence of this far
away structure of nature?
Did you know that the Sun is our nearest star? Many stars are far away from
us, so by studying the properties of the Sun we are able to estimate the
distances to other stars using their radiation. As if that’s not enough,
scientist like Golden Nyambuya ( the Zimbabwean stalwart) spend most of
their days trying to understand and predict how these far away objects are
formed. They even predict the constituents of these stars. That’s how
simple and interesting science can be.
This is written by Donald Mabedle Ngobeni
From N’wamankena-Village in Giyani