Video: Stellar bubble creates ‘pillars of creation’

Did bubbles from stars create the “pillars of creation”? (Image: NASA, ESA, STScI, J. Hester and P. Scowen (Arizona State University))

Building a towering cosmic icon may be as easy as blowing bubbles. Simulations of the billowing wind from a massive star may reveal how the famous “pillars of creation” were created.

The finger-like columns of interstellar gas and dust known as the pillars of creation are part of the Eagle Nebula, a star-forming region about 7000 light years away from Earth. A spectacular image snapped by the Hubble Space Telescope in 1995 catapulted the pillars to stardom.


The dense columns of gas are being sculpted and eroded by ultraviolet radiation from the incredibly massive stars that live in the nebula. Detailed images from multiple telescopes also show dense clumps inside the pillars that suggest new stars are being born.

Scott Balfour at Cardiff University, UK, wanted to understand how such massive stars are affecting their birthplaces. He made a computer simulation of the birth of a very massive star, which emerges when a dense cloud of hydrogen gas collapses under its own weight. He then mimicked stellar life over a 1.6-million-year period. As with real stars, the model star had powerful winds of radiation that created a giant bubble, which collected and compressed the leftover dust and gas as it grew.

Bubbling birth

The model tested different intensities of the star’s UV radiation. In runs with the lowest UV output, the bubble expanded and then collapsed back in on itself. When the star pumped out the most UV light, the bubble just kept expanding, and the simulation yielded bright rimmed clouds and pillars. But these structures weren’t dense enough to lead to the creation of new stars, a hallmark of the real pillars.

Stellar nurseries appeared only when the UV output was “just right” – the bubble expanded, contracted a little and then stopped, disintegrating at the edges. As the bubble fell apart, it left a halo of scraggly trunk-like columns of gas that were dense enough to give birth to new stars inside.

The work neatly reproduces cloud structures like the iconic pillars, suggesting that they could have been created by a stellar bubble, says Balfour, who presented the work this week at the Royal Astronomical Society National Astronomy Meeting in Portsmouth, UK. He says the model also shows that the role of massive stars in sparking the births of new stars is more complex than imagined.

The role that massive stars play in triggering new star formation has been in debate for a while, says Harold Yorke at NASA’s Jet Propulsion Laboratory in Pasadena, California. Balfour’s simulation adds a level of sophistication to how and when such star formation might happen, he says.