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 man-made 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 killer-electrons constitute a potential danger to orbiting satellites, space stations and astronauts as well as having the capability to cause power-outages 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.