Carl Sagan famously spoke of the Pale Blue Dot photo taken from the Voyager I spacecraft, referring to it as a symbol hope and humility that would change our perspective as a species. That all of humanity and all of our world’s history is contained on a tiny speck in the Cosmos.
|“… To me, it underscores our responsibility to deal more kindly with one another and to preserve and cherish the pale blue dot, the only home we’ve ever known.”
– Dr. Carl Sagan
We now live in a time when we understand our galaxy to be filled with such worlds. The Kepler space telescope has shown us this. This does not take away from Dr. Sagan’s statement, not in the least. Rather, it underscores his statement and should renew our resolve to protect our little corner of the Cosmos. In my view, it is because we are not unique that we must cherish our world and each other all the more.
By one estimate, there are perhaps 100 Billion worlds in our galaxy alone, many of which are small rocky worlds like our own, perhaps some with a blueish hue similar to our world. Kepler has been a hugely successful mission. At the time of writing, Kepler has found 132 confirmed exoplanets (planets in orbit around stars other than our own Sun), and 2740 exoplanetary candidates which await confirmation. The result is that we now know our universe to be filled with planets. This is a hugely exciting find, and one which should again change our perspective of the Cosmos and of humanity and of our world.
Last November, the Kepler spacecraft has completed its primary three year mission, and is now onto an extended mission. And although the spacecraft has in recent days had a partial mechanical failure which forced the spacecraft to be placed in safe-mode, I am confident that the team will get it back up and running and doing more great science.
All of these worlds, scattered through our universe, some of which may be quite like our own, are themselves Pale Dots, some perhaps blue or red or yellowish or green. Each of these worlds is too far for us to image directly, we only know of them through other methods of detection, such as the transit method used by the Kepler telescope. Some of these worlds may host life such as what we are familiar with here on Earth, or it may be vastly different in every respect. Some smaller fraction may even host intelligent life, perhaps looking back on us with their own space telescopes with the same wonder and amazement at the abundance of planets in the Cosmos that we feel looking back at them. This is Kepler’s gift to us. We should meet this new knowledge with an open mind and with humility, and above all, with wonder in our eyes.