They
put a man on the moon
To
boldly go...
(April
27, 2000, Gazette)
Dr. Danny Summers
Photo
by Chris Hammond
By
Andris Petersons
SPARK
student
The
prosects for space exploration look exciting. Many more satellites
will be sent into space, will range as far as the planet Pluto,
and even land on a comet. Living on a moon base will probably
soon be a fact of life and an astronaut will walk on Mars in
the foreseeable future.
Space
challenges our curiosity and everything seems possible. It may
not be long before tourists can buy a ticket to the moon and
gaze back at the Earth.
Space
physics is a new description of a very old science. Modern space
physics started about 40 years ago with the advent of manmade
satellites. Dr. Danny Summers does mathematical modelling in
space physics, choosing equations carefully to model interesting
space phenomena. He formulates two kinds of model: models that
are based on physical theory and models that are based on data
from scientific satellites. The models relate to such phenomena
as geomagnetic storms, relativistic particles and waves in the
earth’s magnetosphere, the solar wind and the dynamics of
Jupiter’s magnetosphere.
“I
am essentially a theorist but my theories must connect with data,”
he said. “Successful mathematical modelling is not only
concerned with describing or explaining scientific phenomena,
but also with predicting what will happen. So modelling can give
information on where exactly satellites should be sent, and what
they should measure.”
Dr.
Summers has studied theoretical space physics since he was a
graduate student. He describes himself as an applied mathematician
doing mathematical modelling in space physics.
“I
have always been interested in mathematics. I have always felt
it is a great thing to study. It connects with the big questions
of science relating to the origin and the nature of the universe.”
According
to Dr. Summers, 99 per cent of the universe is plasma.
“Broadly
speaking we are surrounded by plasma. Solid planets constitute
a very tiny per cent of the matter in the universe. The stars,
the galaxies, interplanetary space, are all plasmas. Plasma is
an ionized gas. If you take a metal solid and heat it, it becomes
liquid. If you continue heating it will become a gas, and if
you still continue heating it will become an ionized gas, a plasma
with electrons and protons moving around freely. And in that
state it is susceptible to control by magnetic fields.”
Recently
Dr. Summers gave a talk at MUN about some basic aspects of space
physics and in particular about the behaviour of electrons in
the Earth’s magnetic field. Geomagnetic storms sometimes
produce highly energetic electrons lasting for several days.
These so called killerelectrons constitute a potential danger
to orbiting satellites, space stations and astronauts as well
as having the capability to cause poweroutages on Earth.
Soon
space weather predictions will be as important as the regular
weather forecasts on Earth. The solar wind has only been recognized
since the earliest space satellites in the 1960s. The solar wind
is an emission of charged particles and magnetic fields from
the sun, enveloping the entire planetary system. The Earth, with
its magnetic field forming a protective barrier, is like a bubble
in the solar wind stream. If there are dramatic events on the
sun, a day or two later we feel the impact. If there is an intense
magnetic storm in space it is felt on Earth too.
Dr.
Summers also talked about the widespread public interest in space.
NASA and other organizations make wonderful Web pages providing
an excellent source of information. There are also some excellent
documentaries on space on cable television. The general public
is more educated about space than it ever was.
Dr.
Summers has given lectures in more than 20 countries. Frequently
he presents papers on space physics at international conferences.
He collaborates with space physics groups at the University of
California, Los Angeles; the British Antarctic Survey, Cambridge;
Kyoto University, Japan, and others.
According
to Dr. Summers, mathematics and physics go together “like
peaches and cream.”
“Mathematics
is not just mental gymnastics. Applied mathematics to me is what
mathematics is all about, applying mathematics to real situations.
You can say that calculus put man on the moon because the trajectory
of the rocket, how the space vehicles are controlled, it is all
in the mathematical equations of motion and the mathematical
description of the physics. All physics is mathematics really.”
Currently
there is an international space station being built. Eventually
we are going to move towards people living in space, colonizing,
surviving, going to Mars and beyond, said Dr. Summers.
“These
are not just fairy stories.” After all, there is not only
the moon up there. Great discoveries are still waiting for us.
Dr.
Summers’ research is funded by NSERC.
SPARK,
Students Promoting Awareness about Research Knowledge, is a NSERC
 funded program designed to encourage writing about research.
