Q&A: Five decades of star-gazing

Dr Grant Christie's fascination with the stars was fuelled by looking at the stars as a teenager through his grandfather's World War I era binoculars. Photo / File

Auckland's Stardome Observatory is celebrating 50 years of star-gazing. Science reporter Jamie Morton talked with astronomer Dr Grant Christie about what's yet to come.

You joined the Auckland Astronomical Society way back in 1966, a year before Stardome opened. Up until that point in time, how would you have described the astronomy scene in our biggest city?

I was only 14 and had just developed a passion for astronomy and didn't know much about the astronomy scene.

But after a year or so I got to meet many of the major players.

Some were committed to doing scientific studies and while I was keen to look at any objects through telescopes, I was mostly interested in trying to make useful observations.

Some of the active amateur astronomers in Auckland at the time did make real observations, but most just enjoyed exploring the night sky.

One who had made many science observations was Ronald McIntosh who also ran the planetarium at the Auckland Museum.

I had visited the planetarium quite a few times after it was installed in 1959.

John Orr had a nice observatory at his home in Mt Albert - the society still has his telescope - and Harry Williams had a large telescope in Mt Eden he had constructed himself.

Quite a few people made their own telescopes at that time because big telescopes were usually too expensive to buy.

I made two telescopes under the guidance of Graham Loftus; he was exceptionally generous with his time and expertise, helping many other others beside me.

Stardome Observatory, under construction in the 1960s. Photo / Supplied

Probably the best thing about the astronomy scene here, which is still true today, is that there is only one astronomical society in Auckland and its membership is very diverse and inclusive.

The society itself began in a ramshackle shed in Symonds St, I believe?

The old "shed" on the east side of Symonds St was the first "Auckland Observatory".

It was close to where the School of Architecture now stands.

The society opened it one night a week for public viewing but they realised it was not satisfactory, in fact it was an embarrassment for the city.

This is what led Professor Percy Burbidge, while president of the Astronomical Society, to start promoting the idea a new, modern observatory for Auckland.

That also must have been a pretty interesting time to be getting into astronomy, with the US and Soviet Russia locked in the space race. Was it this that got you interested in astronomy, or did your curiosity go back further?

I can't remember not being very interested in astronomy and everything to do with space.

As a youngster aged five I do remember my grandmother taking me outside one night to see it we could spot Sputnik but sadly we didn't see it.

I longed to get a chance to look through a real telescope.

By the time I was in my early teenage years, I used my grandfather's binoculars from the First World War to look at the stars.

That was a memorable experience I've never forgotten.

Even as old as they were, they showed many more stars, the moons of Jupiter and craters on the Moon.

Stardome Observatory, pictured around the time of its opening, in 1967. Photo / Supplied

I followed all the space race developments, often from the weekly articles by Mr McIntosh in the New Zealand Herald.

I cut everything out but unfortunately I didn't keep those hundreds of cuttings.

With the new observatory came the Carl Zeiss telescope. Can you tell us a little about this and how it changed the face of astronomy in New Zealand?

The new observatory housed the Edith Winstone Blackwell Telescope.

The telescope was made by Zeiss, then based in East Germany, and was at that time the largest telescope in New Zealand, with a 50cm aperture.

The public attendances were huge, keen to see the Moon and planets with their own eyes.

Even located within a big city, the 50cm Zeiss telescope could see fainter stars than other telescopes in the country at that time.

The Auckland Astronomical Society members, now responsible for operating the new observatory, were very keen to see the telescope used for science as well as for regular public viewing.

A number of possible observational programmes were discussed and the active observers mostly concentrated on studying the behaviour of stars known to vary in brightness.

Some stars changed fast - like a nova that suddenly explodes - while many others change in a cyclic way as they slowly pulsate.

Also of great interest were pairs of stars orbiting each other that caused their light to increase and decrease as first one, then the other, was eclipsed by its companion.

The finishing touches are applied to Stardome before its opening 50 years ago. Photo / Supplied

Sometimes these stars could interact with each other causing sudden outbursts but little was known about the details of their lives in the 1960s.

The observatory has published hundreds of scientific papers on variable stars, many in collaboration with professional astronomers around the world.

In terms of New Zealand astronomy, what Kiwi-led discoveries and developments over the last couple of decades would stand out as highlights for you?

Undoubtedly it was being part of a international team that detected planets orbiting distant stars.

This would have been an outrageous idea when the observatory opened but as imaging technology and computers advanced, from 2003 it became technically possible to do this.

Kiwi astronomers played a significant role in developing this technique, notably Profesor Phil Yock and Dr Ian Bond.

They established the New Zealand-Japan collaboration called MOA (Microlensing Observations in Astrophysics) and installed the large 1.8m MOA telescope at Mt John Observatory near Tekapo.

Our observatory was part of a different international collaboration (Microlensing Follow-up Network - MicroFUN) that followed up on events being detected by MOA at Mt John and another similar telescope in Chile.

During our involvement, Stardome Observatory contributed to the discovery of more than 20 planets orbiting distant stars.

While these numbers are small, each discovery has told a great deal about the types of planetary systems that are common in our galaxy.

School children check out the Carl Zeiss telescope in this 1992 picture. Photo / Supplied

And what, in world astronomy generally, have been the most dramatic things you?ve witnessed: the Moon landing? The Mars Rover or Rosetta comet landings? Some of recent leaps around exoplanet discoveries or physics breakthroughs?

The Apollo Moon landings were truly amazing.

For me the next standout moments came from the two Voyager spacecraft that flew past the planets of the outer solar system - Jupiter, Saturn, Uranus and Neptune.

As each planet was reached, they were successively transformed from the blurred views we get through telescopes on Earth into finely detailed sights that no-one could ever have imagined.

The exploration of Mars that started in earnest with the Viking orbiters and landers gave us the first really clear views of Mars as a world and it was quite unlike Earth.

Mars still remains a major interest today.

The discovery of planets orbiting other stars has been our major interest over the last decade. We are learning that planets are very common and almost all stars must have them.

Stardome Observatory, as it is today. Photo / Supplied

The detection and mapping of the cosmic background radiation - the relic radiation from the Big Bang - has confirmed that the Big Bang happened and this science has allowed cosmologists to tell us a great deal about the formation of the Universe and how it evolved through to what we see today.

Finally, it was outstanding to see the detection of gravitational waves in 2015 as two massive black holes merged in galaxy three billion light-years from us.

This amazing confirmation of the Theory of Relativity came 100 years after Einstein first predicted this phenomenon.

Today New Zealand seems to be poised to play a bigger part in the space community. We?re about to see Rocket Lab's take-off from Mahia; we've got teams of scientists working on both the Square Kilometre Array radio telescope and the Large Synoptic Survey Telescope; and AUT has even helped out with some of the first private space launches. Do you expect this contribution will grow?

Yes I do.

New Zealand may be small but it occupies an important place on the globe.

We are surrounded by vast oceans and modern astronomy often requires the coordinated efforts of many observatories around the Earth.

New Zealand therefore provides a vital link for studies where continuous monitoring of an object is needed.

Stardome astronomer Dr Grant Christie has been involved with the Auckland observatory for much of its 50 years. Photo / File

Our country is the first to see objects that have set for the great observatories in Chile and the we see them several hours ahead of observatories in Australia.

The future of astronomy and astrophysics involves huge budget projects and our astronomers are now actively engaged in quite a number of them.

It will be a notable milestone for Kiwi "know-how" to see regular launches from Rocket Lab's new launch facility at Mahia Peninsula later this year.

I'm sure there will be hundreds more launches in the future.

Stardome regularly hosts school and family groups. Do you believe that old childhood sense of wonder about the stars and space is still there in our kids today?

I certainly do.

I personally remember the thrill of learning about space and the wider Universe when I was young.

I see it almost every day with the children that visit the Stardome to learn about space.

We now know so much more than we did 50 years ago but the most important lesson has been to appreciate just how much more there remains to be discovered.

In reality we've just started to scratch the surface.

The discovery of life beyond the Earth is something that almost everyone cares about.

It is that question I get asked most often by people of all ages.

Lastly: what landmark achievements in space do you expect to see made within the remainder of your lifetime - and what further big leaps do you think will probably come within this century?

I expect that the detection of life beyond Earth will be the biggest advance so I hope it does happen in my lifetime.

Understanding of the dynamics of our planet, particularly its climate, and stabilising it in the near future is the most important issue we face as a species.

If we render Earth uninhabitable we already know enough about the Universe to know there is no practical backup plan.