By Pesi Fonua

The human race has around five billion years to plan their evacuation from planet earth, says scientist Chas A. Egan, Tonga's only astrophysicist, "because five billion years from now the sun will burn itself out and life on earth will not be sustainable."

But for the moment, Chas, who calls Kanokupolu home, has his feet on the ground and enjoys gazing into Tonga's beautiful clear skies on his summer holiday here.

During the past five years he has been at the Australian National University in Canberra, working toward a Ph.D. in astrophysics, looking at the origins of the universe.

Chas (26), the son of artists Shane and Chris Egan of Kanolupolu, was a Tonga High School Dux. He did his undergraduate studies in Brisbane before he left for Sydney to get into to what he was really interested in, "Physics, Gravity and the Stars."

Chas simplifies astrophysics, as a study of "life, the universe, and space."

He says he has always been interested in nature and the environment, when he was a youngster surfing around at Kanokupolu and going to school in Tonga, particularly at Tonga High School, "where there was so much emphasis on science. With art it was only music, whereas with science there was biology, chemistry and physics. So when I went to university, I was interested in science.

"I was very good in science, and later I became very interested in physics, gravity and the stars," says Chas.

Research

"I have been in university for nearly 10 years, it is too long, but in a couple of months I am getting what I want, and I should have an interesting career. The hard thing for me is that I can't have Tonga as a part of my life because I will always be working on a research program within a university.

"I am doing new research, like what is happening to the future? The challenge is can we get to another planet before ours burns out?"

Chas says that during the next five billion years we have to identify a new planet, work out how to emigrate there, and work out how to turn the new planet into a liveable planet, so that we can grow plants and be able to live a normal earthly life style.

All this may sound like science fiction, but it gives scientists much to think about.

"As they say, the science fiction of today is tomorrow's reality, and there are scientists who are already looking into how to change the atmosphere of a new planet, and introduce a type of bacteria that breathes out oxygen in order to make life possible."

Big Bang

Chas believes that the question of the origin of life, "Predated science altogether, so there are theological explanations to where we come from by the ancient Egyptians and the Greeks and so on, but according to scientists, the beginning of life was with the Big Bang that took place about 14 billion years ago.

Chas studies satellite pictures of the cosmic microwave background, or the left over light and heat glow, of the universe and uses the details about the distribution of the hot and cold spots to determine some important numbers, such as the density, the curvature, the expansion rate and age of the universe.

Working with other physicists he has published research papers with impressive titles like "Dark-Energy Dynamics Required to Solve the Cosmic Coincidence" and "The Cosmic Coincidence as a Temporal Selection Effect Produced by the Age Distribution of Terrestrial Planets in the Universe."

The universe is expanding, explains Chas. It starts off small and hot at the "Big Bang" and then later the stars and galaxies start to form, then a mysterious force called "dark energy" causes the universe to accelerate.

"Dark energy is weird because we don't know what it is or where it is from, but we know how it must behave," says Chas who likes to speculate about why dark energy has the properties it does.

"Scientists have a way of measuring the distance between the stars. All the stars are moving away from each other, so if you take that motion and reverse backward there was time in the past when everything was in the same place and that was the Big Bang, and based on our measurement that was thirteen or fourteen billion years, which is three times the age of the earth. The earth is about four billion years old."

Expanding forever

The theory of the Big Bang was discovered by Edwin Hubble about 90 years ago, says Chas, and since then we have made better measurements and better observations, and the theory still works now as it did then, and it's accepted by scientists that that was how life began, with the Big Bang.

"Following the Big Bang one of the questions of the future was whether it would keep on expanding or because of gravity it would re-collapse.

"Until about 10 years ago we thought it was going to re-collapse, and then some of the new measurements that we got 10 years ago told us that it would expand forever and that has very big consequences, because maybe the human civilization can live forever. So the universe looks as though it was going to keep expanding out but it will get cold and the stars will burn out and it will be dark and cold. It will be an interesting future to think about."

"The distance between our galaxy and the next galaxy will get further apart.

"Everything that you see in our sky is part of our galaxy and there are about hundred billion stars in a galaxy, but there are about hundred billion galaxies in the whole universe, so we are only a very small part of the whole universe," says Chas.

Chas said, that all that is known that you can pack everything in the universe into something smaller than an atom, and from that 'something' the Big Bang took place. "Before the Big Bang we don't know.

"We don't know the reason why there is life, we don't know why the Big Bang happened; we don't know the meaning of life. That is difficult for scientists because we can't measure it. Theologians are good at answering "why" questions and scientists are good at answering "what" questions.

"There are religious scientists in my field and some of the Christian scientists say that the Big Bang theory fits in well with their religion because God caused the Big Bang and that was the start of everything.

"There was the Big Bang, the stars formed, then the planets, then we got human life after that. A lot of things have to happen before we have human life," he says.

Chas does not believe that the earth was created in seven days. "Metaphorically speaking, a day did not mean 'one day'. I am not religious and there is a lot of stuff out there that you can over-simplify; there is a lot of stuff there that you can't prove or disprove," he says.

Beautiful sky

"The beautiful thing about Tonga compared to where I work in Australia is that here you can see a very beautiful sky. We have a very good telescope [in Australia], but here it is really good to be able to see a beautiful sky," he says.