Dit blog is in het Engels omdat het de voertaal is van TEDx. Ik maak er dus geen gewoonte van ;-). Dit blog verschijnt zo snel mogelijk ook op de site van TEDxHaarlem.

Lucas Ellerbroek is a young promovendus at the University of Amsterdam and does research about the birth of stars. Some DWDD-watchers (a Dutch tv show) may know him from a visit at the DWDD studios in January 2012.

And he was here, in his hometown Haarlem in the historic Teylers Museum, on stage as a TEDx-speaker. The museum he visited with his grandpa (‘Opa’), some 20 years ago for the very first time. As a 9-year-old he started to ask his Opa too many questions about the world around him, so Opa took him to the Teylers Museum and its rooms full of fossils, skeletons and machines.

Keep asking questions

The Teylers’ 200-year-old planetarium he shows on the screen and is still in the museum and on stage, is the same one he asked his Opa about when he visited the museum for the first time: how does it work? What are all those marbles? How come we can live on a little ball like that and how come we do not fall off? Are these 8 the only ones that exist?

200 Years ago, and even 20 years ago, these were all the planets we knew. It is only since 1995 that astronomers found a planet outside of our own universe, where the last 5 years the numbers of these planet-findings exponentially increased.

After graduation and a visit to the jungle whilst staring at the nightly skies full of stars, Lucas wondered: are we the only ones? Is there another place where we can find other creatures? There must be.

And he was not the only astronomer that was really looking for an answer to this question. How can we as astronomers prove that there must be life, elsewhere in the universe? By finding counterexamples, a copy of the earth. By looking for ourselves.

4 basic elements

And that’s exactly what he and a lot of his colleague-astronomers do: finding the 4 basic elements that are conditions for life on other places in the universe: earth, fire, water, air.

This quote from Lucas results in a seriously interesting treatise about how you can find a planet thats contains possibly life-elements. Like: find fire because fire needs energy, then you have a star and most of them have a planet moving around it. Kepler found some great exoplanets – planets outside our solar system – the last 4 years until he vansihed last week. Look at the Goldilocks zone, find water and you know the temperature of the planet: too hot = water evaporates, too cold = water will freeze. Find oxygen, air: with a new to build telescope we will be able to separate the light from the planet from that of the star so we can see, by certain light and contrast, if the planet has oxygen.

The little pale blue dot

Why does Lucas do this research? He shows us a poorly made picture made by the NASA-satellite Voyager. He points at something I can hardly see and asks: ‘do you see the little pale blue dot? I will help you. Look, here. That’s us.’ And he immediately illustrates my feelings with one question: ‘This tiny pale blue dot, this Planet Earth, makes you feel pretty small and insignificant, right? But such a little pale blue dot, makes all the difference. That would be a revolutionarily breakthrough, because that’s a place where there can be other life forms.’


20 years after he visited the Teylers Museum and saw this planetarium for the very first time, we can fill a whole oval room or two with planetaria like this one. All of them from different universes. And he cannot wait to take his grandchildren to the museum. He wants to show them a whole room filled with planetaria and say: ‘this little marble is us. You see that other planetarium with that little marble? There’s another life form there…’