In July 2010, Canadian astronomers at the University of Western Ontario announced the first evidence of naturally forming complex carbon-based compounds called fullerene, informally known as “buckyballs,” in a planetary nebula about 6500 light-years distant from our own solar system. Although the presence of these compounds is not direct evidence of the presence of life in planetary nebula Tc1, the discovery is still exciting because, according to our present understanding of the origins of life, the formation of complex organic compounds is a necessary precursor to life. The more we know about conditions in which large organic compounds can originate in space, the more we can unerstand about the existence of life – and the more common those conditions are, the more likely that life is abundant in our galaxy, and perhaps in the universe as a whole.
Buckyballs are large spherical compounds made up of carbon, in which the molecular bonds have formed in such a way as to form large, hollow ball-shaped spheres rather than more solid clumps of bonded atoms. The existence of Buckyball molecules containing sixty carbon atoms was first predicted by Japanese researchers, and then discovered in the 1980s by a number of scientists who went on to be awarded the Nobel Prize. The informal name “Buckyball” comes from fullerene’s full name, Buckminsterfullerene, inspired by geodesic dome designer Richard Buckminster Fuller.
To date, most of the research involving buckyballs has involved highly technological applications in an artificial setting, like using them in military armour, in certain medicines (especially antibiotics and anti-cancer drugs), and in certain new physics experiments. They do not play any known rule in the evolution of life, either here on Earth or anywhere else in the universe. However, the discovery of naturally occurring buckyballs in planetary nebulae Tc1 is important because it gives us further knowledge about the nature of carbon in the universe – and, therefore, the nature of any life which might arise from carbon.
It was assumed that buckyballs were not a significant naturally occurring compound, but analysis of the Tc nebula using the newly operational Spitzer Space Telescope proved otherwise. The University of Western Ontario team was able to establish that carbon in Tc1 was forming into these complex spherical compounds instead of other, simpler formations they had initially expected.
For the moment, all that can be concluded from the Tc1 study is that there is a possible answer to the reason why, in certain cases, scientists believe less light is received from interstellar sources than it ought to be: some of that light is being absorbed into the very large buckyball molecules in certain nebulae. What is also fascinating, to the Ontario team, is how fortunate they were to spot this phenomenon. Their model suggests that buckyballs probably develop naturally only for a very short time period. Tc1 is a planetary nebula surrounding a white dwarf – the ember left over after the death of a star like our own Sun. The buckyballs themselves probably develop over a period lasting only centuries (whereas astronomical timespans are usually measured in millions of years), and within a few more will have cooled to the point where telescopes like the Spitzer can no longer detect them.
At the same time, the discovery of the buckyballs is significant for our understanding of life in the universe. The more carbon present around other stars, at least according to our best understanding of how life develops, the more complex organic compounds might be likely to form and eventually lead to life. Moreover, if a large proportion of carbon around a dead star is even for a brief period tied up in these buckyball molecules, then the carbon that currently makes up our bodies as well as those of all other life forms on Earth once joined together in those very same molecules. This could be an important step in understanding the role of carbon in the history of the universe, of stars, and of life itself which scientists until this year had not even realized existed.