The Pillars of Creation in the Eagle Nebula taken by the Hubble Space Telescope in 1995

The Hubble Space Telescope almost didn’t make it. Carried aloft in 1990 aboard the space shuttle ­Atlantis, it was over-budget, years behind schedule and, when it finally reached orbit, nearsighted, its 8-foot mirror distorted as a result of a manufacturing flaw.

It would not be until 1993 that a repair mission would bring Hubble online. Finally, on April 1, 1995, the telescope delivered the goods, capturing an image of the universe so clear and deep that it has come to be known as Pillars of Creation.

What Hubble photographed is the Eagle Nebula, a star-forming patch of space 6,500 light-years from Earth in the constellation Serpens Cauda. The great smokestacks are vast clouds of interstellar dust, shaped by the high-energy winds blowing out from nearby stars (the black portion in the top right is from the magnification of one of Hubble’s four cameras).

But the science of the pillars has been the lesser part of their significance. Both the oddness and the enormousness of the formation—the pillars are 5 light-years, or 30 trillion miles, long—awed, thrilled and humbled in equal measure. One image achieved what a thousand astronomy symposia never could.