Predicting the future is a mug’s game.
When I reflect back on what we thought we knew at the start of my research career in the mid-1990s, I sound like a wizened octogenarian, recalling a simpler time long ago. Only 15 years ago, the big debate in astronomy was whether the universe was 10 billion years old or 20 billion years old.
If you had asked me back then where we might be by the year 2011, I and most other astronomers would have said, without hesitation, that by 2011 we would finally know whether 10 billion or 20 billion years was the true age of the universe.
So here we are in 2011: which answer is right? The answer, as is so often the case in science, is “none of the above”. The latest results from NASA’s WMAP satellite suggest the universe is 13.75 billion years old, with a margin of error of 0.11 billion years. This makes it clear that trying to gaze into the cosmic crystal ball is always going to be a foolhardy exercise.
That said, here is my take on where I think astronomy might be 40 years from now, in the year 2051.
The dark universe
Not only were we way out in the mid-1990s with our best guesses for the age of the universe, we weren’t even asking the right question. It turns out that the age of the universe is mere housekeeping: far more pressing is the issue of what the universe is made of.
We now know only 5% of the universe is normal matter (atoms, protons, electrons, etc.), with the rest being either dark matter or dark energy, neither of which we understand in any way.
But 40 years from now, we will understand the nature of both dark matter and dark energy in considerable detail. This won’t just involve tacking some extra ideas on to our current understanding – it will require a wholesale revision of our standard models of cosmology.
While astronomers cut back the number of planets in our own solar system from nine to eight in 2006, we have more than compensated for this with the many hundreds of planets we have now discovered orbiting other stars.
Well before the year 2051, we will have succeeded in identifying other planets quite similar to Earth: rocky bodies about 12,000km across, in orbits roughly a year long, around sun-like stars. These discoveries won’t just be entries in some master catalogue – in a few cases we’ll have made maps of the surfaces of these planets.
We’ll have seen clouds, oceans, continents and ice caps, and perhaps even evidence for photosynthesis or other signatures of life.
In 2051, plans will be in train to launch high-speed robotic probes that will visit the nearest of these distant worlds. These probes will then transmit their findings back to Earth so we can study these planets in spectacular detail.
One of the most striking predictions of Einstein’s Theory of General Relativity is that moving bodies generate ripples in space-time that spread out across the universe at the speed of light.
While you’re reading this, you’re being infinitesimally squeezed and stretched by gravitational waves from distant black holes, billions of light years away. Well, that’s the theory, but gravity waves are yet to have been seen directly.
But by 2051, not only will gravity waves have been clearly detected (with a guaranteed Nobel Prize for whoever discovers them), but gravity-wave astronomy will be a fully-fledged component of modern astrophysics. Astronomers will routinely use “gravity-wave telescopes” to study exotic cosmic phenomena, the existence of which we have not yet even considered.
Time will tell whether my predictions are accurate. But for me it’s a win-win situation. If my forecasts above come true, I’ll be thrilled. But the more likely alternative is that the above topics will become passé in far less than 40 years, and that the important questions in astronomy will be centred on even more exciting topics than what I’ve proposed.
Stand by for my follow-up piece that I’ll write for The Conversation in 2051 to see how my predictions fared.
Which of the above discoveries would you most like to see? What are your predictions for the future of astronomy? Leave your views below.