© Copyright, Frank White, 2017, All Rights Reserved
In 1990, the Voyager spacecraft looked back from beyond Neptune and took a picture of our home planet. Like the iconic views of the Earth from orbit or the moon that introduced us to “the Overview Effect,” (1) this photograph provided us with a new understanding of our place in the universe, thoughtfully interpreted by the visionary astronomer and cosmologist Carl Sagan.
His beautiful meditation on the photo, in which he coined the now-famous phrase, “Pale Blue Dot,” brings home once again the precious and provisional nature of life on Earth. In Sagan’s words:
From this distant vantage point, the Earth might not seem of any particular interest. But for us, it's different. Consider again that dot. That's here. That's home. That's us.
On it, everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. (2)
One way of seeing all forms of space exploration, whether human or robotic, and including Earth-based astronomy, is that its purpose is to facilitate a shift in human awareness of ourselves and the universe. Another way of saying it is that exploration creates an expanded sense of our identity as a species.
Seeing the Earth from orbit offers the classic example of the Overview Effect. The astronaut realizes that the atmosphere protecting us from the harsh environment of outer space is incredibly thin, that there are no borders or boundaries between countries, and that our planet is a whole system of which we are a part. He or she may have a heightened concern for the environment and a greater humanitarian impulse. (3)
Some astronauts achieved another level of insight, which I have called “the Copernican Perspective.” They came to understand that Copernicus was right: while we are a part of the Earth, the Earth in turn is a part of the solar system.
The “pale blue dot” photo so aptly described by Sagan exemplifies the Copernican Perspective, because it is so very different from orbital or lunar views of the Earth. From a few hundred miles out, our home planet fills the field of vision, and even from the moon, it is a recognizable image. From the edge of the solar system, however, our planet really is a dot—hard to see and incredibly small. It is reminiscent of looking at a cell through a microscope. How could all of human history be contained within that small sphere?
Another Pale Blue Dot?
Today, a new “pale blue dot” project has emerged and is gaining attention for its audacity and potential contribution to our perspective on life in the universe. “Project Blue: Join the Search for Another Earth” is dedicated not only to finding other “pale blue dots” but also to photographing them directly. This initiative aims to image planets orbiting within the triple-star system nearest to our own solar system, Alpha Centauri. (4)
If successful, this undertaking could represent a monumental breakthrough in our perception of ourselves and the universe. We cannot predict in advance the impact of such an image, any more than we knew what the Apollo program’s photos of the whole Earth would do. However, it seems safe to say that it will have a significant effect on us.
Looking for planets in the Alpha Centauri system is especially important because any thoughtful examination of the Search for Extraterrestrial Intelligence (SETI) suggests that we should focus our attention not only on habitable planets but also on those that are close to Earth and about the same age.
Recent discoveries by the Kepler space telescope suggest that there are a billion habitable planets in our galaxy alone. (5) We assume that technological civilizations like our own might have evolved on at least some of these worlds and we can have a dialogue with them. That is the SETI dream, at least.
The problem is this: not just any habitable planet will do. If we received a signal from an exoplanet that is 500 light-years away, for example, it would take 500 years for our response to reach them, and another 500 years to hear back. In the meantime, both civilizations would have evolved to the point that the information sharing might be meaningless. The problem only grows with more distant exoplanets.
Moreover, if an exoplanet is much older than the Earth or much younger, any civilization evolving there might not have the means to communicate with us (younger) or not have any interest in doing so (older). (6)
This is where “joining the search for another Earth” comes in. Alpha Centauri is only 4.3 light-years away, and all the stars are about the same age as our sun. This is a coincidence that really demands our attention, and Project Blue has responded.
Our current detection techniques tell us that there is a planet with a mass similar to that of Earth, denoted as Proxima b by scientists, within the habitable zone of one of the suns. Project Blue will not attempt to image this particular exoplanet because it is too close to its star for visual detection. However, the existence of Proxima b suggests that the other two suns in the Alpha Centauri system might host similar Earth-size rocky planets.
It is a conceptual leap to transition from this evidence to the expectation that there might be intelligent life in the Alpha Centauri system, but if so, the payoff would be huge: a dialogue could happen in eight- or nine-year intervals between compatible civilizations.
Even if there is not a communicating society of extraterrestrials so close to Earth, Project Blue’s success might be historic. Could there be another “pale blue dot” in the Alpha Centauri system? If the original photo of Earth was “mind-blowing,” consider what would happen if we could see an “Earth twin” directly.
This is the goal and the promise of “Join the Search for Another Earth,” an audacious and independent research effort that has launched a crowdfunding initiative on Indiegogo. (7) The stakes are high and Project Blue deserves an equally high level of support.
- Frank White, The Overview Effect: Space Exploration and Human Evolution, American Institute of Aeronautics and Astronautics, Third Edition, Reston, VA, 2014.
- Carl Sagan, quoted from his 1994 book, “Pale Blue Dot: A Vision of the Human Future in Space”,, see Business Insider, http://www.businessinsider.com/pale-blue-dot-carl-sagan-2016-1
- The Overview Effect, ibid.
- “The Search for Earth Proxima,” https://vimeo.com/174313049
- Frank White, “The Impact of Contact,” unpublished manuscript, available on request, 2016.
About the Author
Frank White is the author of The Overview Effect: Space Exploration and Human Evolution, first published in 1987 and re-issued in 1998. A member of the Harvard College Class of 1966, Frank graduated magna cum laude and was elected to Phi Beta Kappa. He attended Oxford University on a Rhodes Scholarship, earning an MPhil in 1969. He is the author or co-author of eight additional books on space exploration and the future, including The SETI Factor; Decision: Earth; Think About Space and March of the Millennia (both with Isaac Asimov), The Ice Chronicles (with Paul Mayewski), and Space Stories (with Kenneth J. Cox and Robbie Davis-Floyd). He also contributed chapters on the Overview Effect to four recently published books on space exploration, Return to the Moon, Beyond Earth, Living in Space, and Space Commerce.
Frank has spoken at numerous conferences on space exploration and space development. In 1988, he delivered the keynote address at the International Space Development Conference in Denver. In 1989, he spoke at George Washington University to mark the 20th anniversary of the Apollo 11 moon landing. He also delivered the keynote address at the first Overview Effect Conference in 2007.
In 2006, the Space Tourism Society awarded Frank a "Certificate of Special Recognition."
In 2008, Frank was one of the speakers at a session of the International Space Development Conference that launched the Overview Institute and announced the signing of the Overview Declaration.
Follow his work here.