GAM 2017 Blog
- Published: Sunday, April 09 2017 07:01
By Tom Gordon
How do you say it? 'Sorry humanity, we didn't find ET.' 'We are unique and we’ll never know why.'
After centuries of looking for other life forms in our universe, we’ve accepted that being alone is a strong possibility. However it’s still not an easy thing to have to admit. Now we are minutes away after 100’s of years of searching, to having to accept the most depressing answer to the question -
...are we alone in the universe?
Data from one of SETI’s (the search for extraterrestrial intelligence) many projects will be arriving from satellites around the Milky Way Galaxy in 5 minutes and will be instantly analysed. This data will essentially give us a definitive answer to this question.
It’s not an easy feeling. 5 minutes to go, and counting …
From late 1984 and for the next 300 or so years after that, SETI has been looking for intelligent Extra-Terrestrial life. It has been an incredible scientific journey and it is now coming to an end, although not due to a lack of funding. SETI has been well funded for decades due to a renewed interest based on the growing possibility that we may indeed be alone. No matter where in the universe that we have looked so far there have been no signs of life, and the number of places in the universe that life can be found is diminishing.
4 minutes to go …
It is also disappointing and sad to consider that the mission of explaining the origins and nature of life in the universe may never be answered. How do we know this? It has to do with the Drake equation. First proposed by radio astronomer Frank Drake in 1961, the equation calculates the number of communicating civilizations by multiplying several variables and it is our best attempt at estimating the probability of intelligent life in the universe It's usually written:
N = R* . fp . ne . fl . fi . fc . L
- N = The number of civilisations in the Milky Way galaxy whose electromagnetic emissions are detectable
- R* = The rate of formation of stars suitable for the development of intelligent life.
- fp = The fraction of those stars with planetary systems.
- ne = The number of planets, per solar system, with an environment suitable for life.
- fl = The fraction of suitable planets on which life actually appears.
- fi = The fraction of life bearing planets on which intelligent life emerges.
- fc = The fraction of civilizations that develop a technology that releases detectable signs of their existence into space.
- L = The length of time such civilizations release detectable signals into space.
We understand the terms in the Drake Equation and have refined them to acceptable levels with more and more satellites, instrumentation, analytical techniques, and testing.
Over time, as the number of parts of the universe that have been searched increases and the observable universe shrinks, SETI has been able to add a new component to the Drake equation. Now, in less than 4 minutes, this new component will be enough to determine if, N, is undefined or not.
The term extra component in the new Drake equation is a difference between the area of Observable Universe, Ou, and the Searched Universe Su. So the new Drake equation,
N = (R* . fp . ne . fl . fi . fc . L) / (Ou - Su)
is a ratio of what we expect to find divided by what we can physically find.
Back in the 20th Century we learned that the edge of the Universe is expanding faster than the speed of light. We’ve known about this phenomenon for just over 300 years. So our observable universe, or the amount of stuff we could ever see in the universe, is getting smaller. If Ou - Su = 0, then we’ve run out of universe to find ET in, and ….
3 Minutes …
With all the scary social implications aside, SETI has done some really great science. We’ve managed to send satellites and probes further away that we ever thought possible, finding out more about our universe, and us.
One of the coolest projects that SETI was involved in was sending a satellite to return with Voyager 1 to Earth. This was to see if there had been any ET interaction with the furthest satellite we’d sent out. To complete the Voyager project SETI needed to replace Voyager 1. So we sent 2 satellites out, one to bring Voyager 1 back and the other to replace Voyager 1. It was called Voyager 2.0 and has recently, in the last 3 years, reached the Oort cloud. It has returned some fascinating results of course, but we found nothing unexpected on Voyager 1 but none of that seems relevant at the moment.
2 minutes …
What if we DO see evidence for ET? Is humanity ready for that result? I’m not sure if we are. Does it even matter? Even if we find ET they’ll most likely move out of the Observable universe before we have any chance of contacting them. That’s an even bigger announcement. 'Hi humanity. We found ET, but we’re too late'.
1 minute …
Quick, to the observatory
We rush to the SETI observatory control room to be amongst our friends and our supporters in this moment that will define, once and for all our place in the universe. If we are alone who wins? Sure we’ve found something out, but at what cost?
30 Seconds …
If this data shows that there is no ET in this last place in the universe for us to look, we probably have our answer ...
10 Seconds …
People want to know if we’re alone. It matters to us. We’re a species of explorers and always have been. To be told that there’s no-one out there to find might diminish some of us as humans.
5 …
For some strange reason I half expected to get a tap on the shoulder just now, turn around and see an Alien waving at me.
4 …
BOO!
Breathe …
3 …
I’m imagining things.
2 …
This is going to be a big couple of days …
1 …
This is going to be a big rest of humanity ...
The end.
Tom Gordon is a science communicator at the School of Physics. His role is to provide and develop outreach programs to, mainly, High school students in order to assist them with their studies, provide mentors and information about University life and expectations. In addition, he runs many other School and holiday programs such as Gifted and Talented workshops and he is the Chair of the School of Physics outreach committee.
He did a degree in Astronomy and Astrophysics as well as a Graduate Diploma in Science Communication at the ANU, then a Masters Degree in Space Studies in France. After returning to Australia he was a High School teacher for 4 years in Sydney, and a stint at the National Measurement Institute as a legal metrology policy officer.His role also extends to media enquiries and publications, as well as in-reach to current university students as well as Science Teachers workshops and forums.
In his spare time he is on the executive of the Parents and Citizens committee at his daughters' school and he has also become involved and very interested in the Australian Political process by joining and being active in a minor political party.
