Professor Sara Seager is devoting the rest of her life to answering the question: Are we alone? Finding an Earth twin might seem like a crazy quest, but when you look at the history of great discoveries, you’ll find that most began with a far out idea.
Finding a planet isn’t easy because the star (or stars) around which a planet orbits shine too brightly to let you see anything nearby. As Professor Seager says: “It’s like us here in Boston looking for a firefly next to a searchlight in San Francisco.” (Interview with New Scientist ) So how do you discover planets?
Right now scientists look for indirect effects. A planet’s gravity tugs at its sun, causing very tiny, but measurable, differences in the star’s center of gravity. Instead, Sara wants to view planets directly. She is working on the JPL starshade project, which will use a space telescope and a sophisticated shade to block a star's light. It’s a tricky technical challenge. First of all, the shade must have a precisely manufactured shape to account for the effects of light diffraction. As you can see in the artist’s rendition, the shade looks like a flower with delicate petals. Secondly, the shade must be located an exact distance from the space telescope so the shade blocks all the light.
Professor Seager has identified planets whose “variety is simply astonishing.” The NASA Exoplanet Travel Bureau even has posters for many of these planets that give you an idea of what space travelers should expect. For example, on Kepler 186f, you could find red grass instead of green due to the lack of conditions for photosynthesis and chlorophyll, which gives Earth plants their green color.
You might think that Sara Seager was born with a quest for finding Earth-like planets. But she didn’t even think about astronomy until she attended an Astronomy Day open house at the University of Toronto. Even then, it was years later that she got hooked on planet hunting.
“I knew I was different from other people from day one, I just didn’t know how the difference would manifest,” she says. “I spent more time daydreaming than anybody I know, and I was such a risk taker. I felt like I always had to live on the edge.” (Interview with Smithsonian Magazine)
When she set her goal to find an Earth twin, her colleagues were doubtful. She points out that the nature of science is to be skeptical. Over time, your either have data to support your theory or you don’t. Her discoveries thus far indicate that if there is an Earth twin, it is within our capability to find it.
These quotes inspire me because they speak to pursuing your passion:
“As a scientist, you have this immense curiosity, stubbornness, resolute will that you will go forward no matter what other people say.” (TED Talk)
“It’s so liberating not to care about what other people are thinking.” (Interview with Smithsonian Magazine)