For the first time, “buckyballs” have been discovered in the cosmos in a solid form.
Until now, the only evidence in space for the bizarre little hollow balls of carbon atoms have been in interstellar gases, but with the help of NASA’s Spitzer Space Telescope, astronomers have discovered buckyballs accumulating and stacking atop one another to form solid particles.
Buckyballs are a nickname for buckminsterfullerines, a geodesic molecular ordering of 60 carbon atoms that resemble the domes designed by American architect and inventor Richard Buckminster Fuller.
Apart from buckyballs that have a curious soccer ball-like shape, the wider family of fullerines are candidates for many industrial applications, from being a superconducting material to hardening body armor. On Earth, buckyballs are found in soot — the carbon-rich residue that remains after a material has combusted. When they become a solid in the bottom of a test tube, buckminsterfullerines take on a brown “goo-like” form.
In 2010, Spitzer discovered buckyballs in a gaseous form in the clouds of planetary nebulae. Planetary nebulae form when stars that are too small to go supernova (like our sun) run out of fuel and die after becoming a red giant. Stellar material is blown into space, forming a huge cloud, or a nebula. It would appear that it is this kind of environment that is conducive to buckyball formation.
Spitzer analyzed the infrared light emitted from the nebulae to find the spectral “fingerprint” of gaseous buckyballs.
Now, while studying a binary star system called XX Ophiuchi — 6,500 light-years from Earth — astronomers detected buckyballs not in a gas form, but accumulated together, forming tiny particles. The light emitted by stacks of buckyballs produces a unique infrared emission.
“These buckyballs are stacked together to form a solid, like oranges in a crate,” said Nye Evans of Keele University in England, lead author of a paper appearing in the Monthly Notices of the Royal Astronomical Society. “The particles we detected are minuscule, far smaller than the width of a hair, but each one would contain stacks of millions of buckyballs.”
Understanding the formation processes behind buckyballs — and stacked solid particles of buckyballs — may be critical for us to understand how life (which is carbon-based) may have started.
“This exciting result suggests that buckyballs are even more widespread in space than the earlier Spitzer results showed,” said Mike Werner, project scientist for Spitzer at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “They may be an important form of carbon, an essential building block for life, throughout the cosmos.”
Images: Top: Buckyballs begin to accumulate together, slowly stacking to form a solid particle. Bottom: As illustrated in this artist’s impression, the buckyballs must eventually stack “like oranges in a crate” to form a solid particle. Credit: NASA/JPL-Caltech