- The Double Star Cluster
The Double Star Cluster
7,000 light years away from Earth and about 500 light years away from each other, are the two clusters of stars known as The Double Star Cluster. In dark sky, the human eye can detect them as a brighter smudge standing out against the northern section of the Milky Way. In reality these two star clusters are not actually with us in Orion Arm of our galaxy, but instead shining through from the larger Perseus Arm where it warps around us at even a greater distance from the Milky Way’s core than we are. Confused? You aren’t the only one! Imagine a couple of fleas arguing about what kind of dog they are on. That’s been astronomers’ challenge in mapping the Milky Way, until the European Space Agency (ESA) sent their spacecraft Gaia to Earth’s Lagrange Point #2. Long before James Webb Space Telescope was sent to that same vantage point, Gaia has been there since 2014 precisely measuring and remeasuring the distance to over 1 billion stars to also calculate their exact motion. Thanks to Gaia we know more about the geography of our galaxy than most Americans do their own planet. The trouble with galactic mapping is that it’s a three-dimensional problem. Let’s keep it simple for now and revert to the ancient technique of pretending constellations are two-dimensional patterns. Now we say The Double Star Cluster halfway between the constellations Cassiopeia and Perseus, and find it there.
The stars that make up constellations are all of different ages and different distances and have no relation to one another except that we humans have connected these same stars with imaginary lines for millennia. All stars begin in star clusters. Like so many siblings, they are born in the same place, from huge clouds of dust and gas called star-birth nebulae. As more and more stars hatch from their cocoons, their combined outward flow of energy, known as stellar wind, pushes away the unused dust and gas revealing a cluster of stars.
As a star ages, it manufactures larger atoms by smashing together small ones. As that ratio changes from mostly hydrogen to increasing amounts helium, carbon, neon, oxygen, silicon, etc. the color of the light the star emits changes. From the color of stars astronomers can determine their relative age. New born stars are blue. They become just white when they in elementary school. Yellow stars like our Sun are in their high school and college years. Orange stars are middle aged. Red stars are senior citizens.
When those red stars run out of fuel they explode as supernovas, weakening the gravitational stability of the cluster causing their siblings on the edges to fall way into deep space. Eventually the entire star cluster falls apart. Those lucky few that wander into interesting alignments as viewed from Earth, get to be recognized as parts of constellations by us humans and apparently many species of migratory birds too.
Stars that are born big age much faster than their smaller siblings. The largest ones race through their entire life-cycle in only just a few million years, where smaller stars like our Sun live for billions of years. This is why the Double Star Cluster has a variety of colorful stars. Star color is subtle, like flavor is to La Croix. It's important to note that all stars are mostly white so what you should set your search image for is the extra tint of light present in addition to white. Astrophotography always reveals more information than the human eye can see through a telescope. This due to lots of biological reasons like, limited contrast ratios, too fast of refresh-rate for color rendition, etc. When showing off this colorful piece of Dark Ranger Telescope Astro Art to an ophthalmologist, they can elaborate. But if they get a little boring you can interrupt with what you've learned about stellar evolution.