The Pillars of Creation are three towering columns of cold gas and dust in the Eagle Nebula, a cloud where new stars are forming about 6,500 light-years from Earth. A light-year is the distance light travels in one year, about 9.46 trillion kilometers. The size given for the pillars is the length of the tallest one, which is about 4 light-years, or 38 trillion kilometers, from top to bottom.

Size

The tallest pillar is the one on the left in the famous photographs taken by the Hubble Space Telescope. Astronomers at the European Southern Observatory (ESO) estimate that it is about 4 light-years long, counting it as one object from top to bottom. That is about twice the height of the pillar on the right. NASA, describing a wider Hubble view that includes the faint base of the columns, gives about 5 light-years.

These lengths are estimates. The pillars rise out of a larger cloud of gas and dust, and their bases are faint and hard to trace. Their lengths also depend on their distance, which NASA and the European Space Agency give as 6,500 light-years and ESO as about 7,000.

The pillars do not all point the same way, either. Observations with ESO's Very Large Telescope in Chile showed that the tip of the left pillar faces Earth. They also showed that this pillar lies behind the cluster of bright stars that lights it, unlike the others.

Size comparisons

• The tallest pillar is about 1.2 parsecs long. A parsec is a unit of distance equal to about 3.26 light-years.
• It is almost as long as the distance from the Sun to Proxima Centauri, about 4.2 light-years.
• If the tallest pillar were shrunk to the height of Mount Everest, 8,849 meters (29,032 feet), the orbit of Neptune would be a circle about 2.1 meters (6.9 feet) across. Earth's orbit would be about 7 centimeters (2.8 inches) across, and the Sun would be a speck a third of a millimeter wide.
• Together, the pillars contain about 200 times as much material as the Sun.

How the pillars formed

Columns like these form in the giant clouds of gas and dust where stars are born. Newly formed, very hot stars give off intense ultraviolet light and fast winds of particles that blow away the thinner gas around them. In the Eagle Nebula these stars belong to a cluster called NGC 6611, which lies above the pillars.

Denser pockets of gas and dust resist this erosion for longer. Each one shades the material behind it, leaving a long, dark column that points away from the bright stars. New stars are forming inside the pillars themselves. Images from the James Webb Space Telescope show young stars that are estimated to be only a few hundred thousand years old.

Pillars of destruction

The same starlight that shapes the pillars is also destroying them. In Hubble's pictures, a bluish haze surrounds their edges. It is gas that has been heated by the nearby stars and is evaporating into space.

ESO's measurements show that the pillars lose about 70 times the mass of the Sun every million years. At that rate, the material they hold now would last only about three million more years. Hubble first photographed the pillars in 1995 and again in 2014, and Webb photographed them in 2022.

Sources

• The Pillars of Creation Revealed in 3D. European Southern Observatory, 2015.
• The Pillars of Creation revisited with MUSE: gas kinematics and high-mass stellar feedback traced by optical spectroscopy. McLeod et al., Monthly Notices of the Royal Astronomical Society, 2015.
• Hubble Goes High Def to Revisit the Iconic 'Pillars of Creation'. NASA, 2015.
• Revisiting an icon. ESA/Hubble, 2015.
• NASA's Webb Takes Star-Filled Portrait of Pillars of Creation. NASA, 2022.
• Measuring the Universe. International Astronomical Union.
• Proxima's orbit around Alpha Centauri. Kervella et al., Astronomy & Astrophysics, 2017.
• 8,848.86 metres. That's the height of Mt Everest now. The Kathmandu Post, 2020.
• Neptune Fact Sheet. NASA, 2024.
• Sun Fact Sheet. NASA, 2024.