The North Star, known as Polaris, is a powerful tool in astrophotography. Deep space photos generally require calibrating equipment with a precise process called Polar Alignment, where we align our telescope to match the axis of Earth’s rotation. Without that calibration, our equipment would have a much harder time compensating for Earth’s 15 degrees of spin per hour. Polaris famously helps travelers navigate without GPS, as it appears fairly stationary in the northern sky. That is to say, the constellations appear to rotate around the North Star, which is how we know that it lines up with Earth’s rotational axis. A similar principle is what makes Polar Alignment effective in astronomy.
Today’s article features three celestial objects that demonstrate the lifecycle of stars like Polaris, or even our own Sun, all photographed from Alameda. We begin with M13, the Hercules Globular Star Cluster.
M13, a cluster of stars in the constellation Hercules. Photo by Evan Gomez-Shwartz.
This is one of over 100 globular star clusters that orbit the core of the Milky Way, and one of several that you can spot with a telescope or binoculars. M13 is composed of hundreds of thousands of stars bound by gravity which are so close together that they crash into one another, giving birth to new stars. Globular clusters contain some of the oldest stars in the Milky Way, but new ones are created over and over within their center. In that way, it’s a look into the beginning of a star’s lifecycle. Let’s look now at another stage of life.
In 1974, the Arecibo Observatory transmitted the famous Arecibo message toward M13. The encoded signal contained information about humanity, DNA, atomic numbers, Earth’s location, and other data. The transmission was intended as a symbolic experiment in reaching out to potential extraterrestrial civilizations. M13 was selected because it is a large and relatively nearby star cluster that happened to be well-positioned during the dedication ceremony. However, since the cluster will drift through space over the thousands of years it will take for the message to arrive, there is debate over whether it will still be in the right position to receive it.
The Crescent Nebula (NGC 6888), located in the constellation Cygnus, shows superheated emissions interacting. Photo by Evan Gomez-Shwartz.
This one is a bit hard to wrap my head around. At its center is WR 136, a massive Wolf-Rayet star—a rare, super-hot, and short-lived stage in a star’s life. Nearing the end of its life, WR 136 is tearing into a shell of gas it emitted about 250,000 years ago. You may have heard of Stellar Winds. Now you’ve seen what power they wield. That shell, known as the Crescent Nebula (NGC 6888), burns where two shockwaves collide—one blasting outward into space, and the other pressing inward toward the star itself.
The unimaginably hot wall of energy ignites the surrounding gases, sculpting the nebula’s distinctive shape. Unlike a supernova, this isn’t the final explosion of a dying star. It’s more like a glimpse of its extreme, turbulent existence. To capture it, I used a special filter tuned to the narrow wavelengths of light those gases emit.
A section of the Veil Nebula (NGC6960) is the aftermath of a star which exploded between 10,000 and 20,000 years ago in the constellation Cygnus. It was 20 times more massive than the Sun. Photo by Evan Gomez-Shwartz.
A supernova occurs in the final stages of a star’s evolution. While supernovas can happen for multiple reasons, in this case the star ran out of fuel and collapsed under its own weight, causing an explosion. This supernova remnant, named the Veil Nebula, reminds us that light carries on after the end of a lifecycle. Even when our shared time comes to a close, whether on Earth or across the galaxy, we leave a supernova behind.
At the time of its explosion, the supernova would have appeared brighter than Venus in the sky, and visible in the daytime. It’s huge. Imagine taking a road trip at the speed of light that lasts 2,400 years from one side to the other—don’t forget to bring snacks! This photo captures only a tiny sliver of the explosion.
Whatever stage you find yourself in, starting fresh, guiding others as a reliable skymark, making shockwaves, or leaving behind beauty as one chapter ends, you’re in good company amongst the stars.
While on vacation at Timber Cove in 2020, Evan Gomez-Shwartz accidentally photographed the Milky Way with his phone. Since then, he’s been taking photos of outer space at every opportunity possible, now with better equipment. The Alameda-based astrophotographer’s favorite subjects to photograph are nebulae and galaxies. Reach him via [email protected]
