Action in the Galactic Atmosphere

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A thin inter-stellar gas envelopes our galaxy, and spreads through the space between its billions of stars.  This cold reservoir of gas was once regarded as a view-blocking nuisance.  We now recognize it, as a complex galactic atmosphere, which exhibits great diversity in it's density, temperature, and composition.

Held in place by the combined gravitational pull of the stars, this space atmosphere is permeated with energetic particles and a magnetic field.  Super nova explosions blow giant bubbles and fountains into it, causing events which ripple into the distant regions of our galaxy.

Just as local atmospheric disturbances on Earth, can impact places on the other side of the globe, changes in the galactic atmosphere can have far-reaching effects on a cosmic scale.  This space atmosphere, which is constantly transformed by matter from dying stars, can transmit huge disturbances across our galaxy.  As the galaxy ages, each generation of stars pollutes the galactic atmosphere with heavy elements.  These are recycled, much as water is recycled on the Earth.

How stars wield power over an entire galaxy is an ongoing mystery to astronomers.  It's thought that the creation of hot ionized gas, produced by high velocity shock waves from super nova, expands into the inter stellar medium, creating giant bubbles in inter-galactic space.

So next time you look through space, remember you are looking through a constantly changing galactic atmosphere.