We first discovered planets orbiting other stars, or exoplanets, back in 1995. I was lucky enough to help write one paper on a particularly famous exoplanetary system in 2004 called HD209458b, nearly ten years later.
Even at this time, many in the scientific community were still deciding when and whether to jump on board and accept the discoveries. It had just all happened so fast. As an example, I recall a visit in 2004 to a major institution in Europe to give a professional talk on astronomy. I agreed to talk about the first galaxies, as planned, and offered also to give some results on my study of HD209458b. The response to that idea was a direct “No, we do not want to hear that.”
At best, some still thought that finding exoplanets was bean counting, and at worst, not scientific at all. I refrained from talking about the exoplanets on that particular day.
Now the situation is very different. Exoplanets and the exploration of their atmospheres and projections of their possible surface compositions takes the spotlight at scientific conferences and major world newspapers alike. There has been a remarkable acceleration of discovery in only 20 years.
We should bear in mind that the stars are not getting any closer to us. Remember that the very nearest star outside of our sun, Proxima Centauri, is about 4 light years away. In more graspable terms, it would take about 100,000 years to fly to this star with our current space-based technology. And every other star is much farther away than this 100,000 year-long “drive.” On top of that, each star is on average 100 billion times brighter than the dim planet that orbits it.
Yet we are finding planets successfully now, and in great numbers, 1284 of them at last count. In Part Two we will take a look at an idea being discussed by NASA to image planets directly using a starshade, the invention of one Professor Lyman Spitzer.