This chicken-and-egg analogy is an issue raised with the discovery of a massive black hole inside a tiny, dwarf galaxy, and it may provide clues to the formation of the universe.
A little Astronomy 101 would help here.
We live on a planet that's part of a solar system that orbits its own sun or star. This star is one of billions that make up our home galaxy, the Milky Way. Scientists now believe that there are billions of other galaxies in the cosmos, containing billions of suns. It's a big universe out there.
The galaxy in question, known as Henize 2-10, is about 30 million light-years away from our celestial neighborhood.
"This is a very strange galaxy in which to find a supermassive black hole," said Amy Reines, the University of Virginia astronomer who discovered the object.
"These things can grow to upwards of 1 billion times the mass of the sun, but we don't know how they get started," Reines said at the American Astronomical Society in Seattle, where she discussed her findings.
Scientists know of the existence of black holes by noticing nearby cosmic material that gets swallowed up by the hole.
A leading theory suggests that black holes and their host galaxies form at the same time, and it's been thought that most large galaxies have a huge, centrally located black hole, surrounded by a swelling or bulge of stars.
The question has always been, which came first, the hole or the galaxy? And observations of the tiny Henize 2-10 galaxy suggest that, while it doesn't appear to have that star bulge, it certainly has the black hole.
"Apparently, you don't have to have a bulge to form a massive black hole," Reines said. "Whether this is a general thing or not, we don't know. We really need to go and look for more examples like this.
"It does suggest that it's at least possible that the black hole formed before the galaxy."
And, oh yes, in case you were wondering, our own Milky Way galaxy contains a central supermassive black hole. At 26,000 light-years away from Earth, it's right around the corner, cosmically speaking.
Astronomers hope this new information will help them understand how galaxies and the rest of the universe were formed.
Reines' black hole research is published in the scientific journal Nature.
Read more at Discovery News.