Lonely Galaxy in an Empty Void

Stars are far apart, especially compared to the everyday distances in human experience.  The fastest a human being has ever travelled is just shy of 40 Km/s, and even at that incredible speed it would take 30,000 years to reach the closest star.  That is an incredible distance no matter how you slice it.  Taking it a step further, most stars in the sky are 20-200 times further away, and that’s just the population of stars we can see.  So if we go beyond and talk about galaxies and the distances between them, we are literally talking astronomical quantities.  Yet even with great distances between galaxies, they still can be classified in groups called ‘clusters,’ and the universe is populated by regions with many galaxies and regions with few galaxies, called ‘voids.’  Yet even with such huge swaths of dark, cold, empty space, we can find lonely and isolated galaxies.

This NASA/ESA HUbble Space Telescope image shows galaxy NGC 6503. The galaxy is at the edge of a strangely empty patch of space called the Local Void. Credit: NASA, ESA

NGC 6503 is one of these lonely galaxies that sits in a great empty space called the local void, which incidentally is close to our local group of galaxies.  It is 18 Million light-years away from the Milky Way, in the constellation Draco.  It’s about one third the size of the Milky Way, spanning only 30,000 light years.

The reason that this galaxy is the subject of ongoing research is that for one, it can teach us about the past interactions that led to its isolation.  It can also tell us about how galaxies evolve naturally in space.  It’s like an experiment in a coffee cup; you want to keep the heat in and measure how long it takes to cool at room temperature, ie how it evolves naturally.  It would help the experiment if you could keep it away from other sources of heat or very cold spaces, since those would change how quickly heat was released and mess up your experiment.

The new Hubble images of the galaxy reveal a dusty spiral structure with no discernible bulge, and the central region is what we call a low ionisation nuclear region (LINER).  The central region of this galaxy is thought to be powered by a starved black hole that has little to no infalling gas to fuel emissions.

It’s a common truth in science that even the most boring and seemingly uninteresting regions can still provide us data and give insights to the larger picture, in the same way every human being is an important part of this large structure of the species we call humanity.

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