Kathleen Rogers

Opinion contributor

Christmas Eve marks the 50th anniversary of “Earthrise,” one of the first photos ever taken of our entire planet. Shot by the crew of the Apollo 8, the first manned mission to orbit the moon, it was a stunning and unexpected holiday present. Even the crew of the space craft, Frank Borman, Jim Lovell and William Anders, were unprepared for what they witnessed. They had spent the better part of the day taking photos of the moon’s surface when Borman turned the spaceship to look at the horizon. The astronauts’ reaction was awe. Anders shouted, “Oh my God, look at that picture over there. Here’s the Earth coming up,” and they grabbed their cameras to take those first remarkable shots, first in black and then quickly in color.

The world’s reaction was also awe. Set against a vast and never-ending backdrop of darkness, the photo of our little blue-and-green planet confirmed something different for each person who viewed it: For some, it confirmed that the Earth was actually round, for others their notion of infinity, and for others still it confirmed the existence of God.

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It also became a blinding confirmation that our Earth, floating in a sea of stars, was vulnerable and needed protecting. The Earth looked so perfect, so radiant, so small. As Command Module Pilot Jim Lovell said, "The vast loneliness is awe-inspiring, and it makes you realize just what you have back there on Earth."

The nascent environmental community agreed, for it confirmed what they already knew — that the Earth’s environment was common to all of us, that the Earth’s natural resources were finite, and that 150 years of unfettered industrial development was having a profound impact on our planet. All of this was easier for everyone to imagine, for everyone to believe, after Earthrise.

Looking back, many people saw a straight trajectory from Earthrise to the first Earth Day 16 months later. Certainly, Earthrise raised the level of ecoconsciousness that had been stirring for almost a decade, even before Rachel Carson’s "Silent Spring" book. But beyond this new consciousness, Earthrise instilled a sense of urgency for those who were already on the front lines battling pollution and making the case that our health and planet were in danger. Earthrise was a confirmation of the righteousness of the endeavor, building confidence in what was a scattered movement into something more cohesive.

Earthrise was the beacon to protect our planet

Sixteen months later, on Earth Day, April 22, 1970, 20 million people came out onto the streets across America, an event that to this day remains the largest civic event in human history.

In those intervening 16 months, the United States had experienced a set of environmental disasters, such as the Santa Barbara oil spill in California and a fire on the Cuyahoga River in Ohio. To the founders and organizers of the first Earth Day, these disasters were harbingers of a future that without action would imperil our blue-and-green planet and the people who live here. To the 20 million people who came out on the streets, Earth Day provided a vehicle for their common aspirations — to protect their little blue planet and themselves.

The 50th anniversary of Earthrise will soon lead to the 50th anniversary of Earth Day on April 22, 2020. The five intervening decades from the first Earth Day gave rise to most of the world’s environmental laws, and not unsurprisingly many more disasters. Most environmentalists are still filled with that same sense of urgency that Earthrise once inspired, and most are convinced that it will take the collective commitment of our nation to make it happen.

From the moon, a photo of our planet might show that not much has changed, but as you draw closer you see the ravages of our indifference. Fifty years ago, Earthrise was the beacon to protect our planet and Earth Day became the measure of that devotion. It is worth remembering that those were times of hope and optimism — and that one single photo could inspire a generation.

Kathleen Rogers is president of the Earth Day Network, the world’s largest recruiter to the environmental movement with thousands of partners in 192 countries. Follow her on Twitter: @Kathleenedn