Orion, An Old Friend

The dark road curved beneath my headlights, and then straightened into a long trough between the trees. An old friend lay resting there, just above the pointed tips of spruce and fir.

Museum Member Vivianne Hanke sketched this image of the constellation of Orion to illustrate a chapter in my first book!

Orion has been my favorite winter constellation for many years. Sometimes subtitled “The Hunter,” it seems apt that Orion is lying on his side these days, perhaps resting up from early mornings of deer hunting. Traditionally, of course, his quarry was more mythical—chasing the beautiful seven sisters of Pleiades, doing battle with Taurus the Bull, fighting a scorpion sent to tame his ego, or hunting the constellation Lepus the Hare.

In Australia and New Zealand, Orion appears upside down, and his distinctive belt and sword are imagined instead as a cooking pot. Perfect for the end of hunting season! Closer to home, some in the Ojibwe culture call this constellation Biboonkeonini, the Winter Maker, as his presence in the night sky heralds winter. Indeed, he can be seen from November to February each year.

Of the four stars that form the rectangular shape of Orion’s body, Betelgeuse is my favorite. This reddish colored star forms Orion’s right shoulder. The red color is not an optical illusion, and it is not due to rusty iron, as is the color on Mars. Betelgeuse is a type of star called a red supergiant, and it gives off most of its light in the near-infrared wavelength, which we cannot see. It is at the opposite end of the spectrum from ultra-violet (UV) light, which is also invisible to humans. Only a small portion (13%) of Betelgeuse’s light is visible to our eyes. But we have built surrogate “eyes”—instruments that can “see” these wavelengths and translate them into beautiful images in the visible spectrum of colors.

Betelgeuse is one of the largest stars ever discovered, and it would be the brightest star in the sky—if we could see that infrared light. Instead, we only observe it as roughly the tenth-brightest star, and its brightness fluctuates.

With the help of powerful telescopes, astrophysicists have seen hotspots and other features on the surface of Betelgeuse. One astronomer characterized Betelgeuse as “an enormous seething restless cauldron of belching plasma.” In 2019, the star blew a huge chunk of its mass into space, and the dust cloud that ensued shaded us from its light. Betelgeuse dimmed by 60%, and then brightened again less than a year later as the dust cleared.

From NASA: “This four-panel illustration shows how the southern region of the rapidly evolving, bright, red supergiant star Betelgeuse suddenly become fainter for several months during late 2019 and early 2020. In the first two panels, a bright, hot blob of plasma is ejected from the emergence of a huge convection cell on the star's surface. In panel three, the outflowing, expelled gas rapidly expands outward. It cools to form an enormous cloud of obscuring dust grains. The final panel reveals the huge dust cloud blocking the light (as seen from Earth) from a quarter of the star's surface.” Credit: NASA, ESA, and E. Wheatley (STScI)

Something that violent can hardly last very long. At about 10 million years old, Betelgeuse is thought to be near the end of its life. It will likely explode into a supernova within the next 100,000 years, and maybe even within tens of years. When it does, it will be visible even in the day, brighter than the moon, and to an outside observer would outshine the entire Milky Way Galaxy.

I was never an astronaut-aspiring space kid, but I did become enthralled with stars once I learned that they, like us, are born and die. Stars arise from clouds of dust, where gravity brings the particles together. Mass builds and gravity increases until hydrogen atoms smashing into each other combine to form helium. Nuclear fusion begins, light shines, and a star is born.

As the star ages and becomes a red giant, helium fuses into carbon, oxygen, nitrogen, magnesium, and eventually iron. But where does the rest of the periodic table come in? Those elements can’t be created during a star’s life. They are conceived during its death.

The heat and energy involved in a large star’s death—in a supernova—are enough to synthesize many more elements, which are all hurled into space to form a supernova remnant, also called a nebula. Nebulas are the birthplaces of stars, and also of planets like Earth. The atoms who coalesced to form the Earth now cycle endlessly through her rocks, her air, her water, and her life. We literally are made of stardust.

Betelgeuse has already used up its supply of hydrogen for nuclear fusion. This means heavier elements are fusing together, and the star’s core is compressed into a hot, dense, ball, while other outer layers have expanded into the huge red mass we see today. Stars like this are rare—we only know of 200 in our galaxy—because they do not live very long.

While I admire the superlative nature of stars like Betelgeuse, I often think about how wonderful our own star is. Our Sun is just the right size, just the right distance, just the right age, and just the right brightness to make life on Earth possible.

This time of year, when gray clouds can hang low for many days in a row, a splash of sunlight on my face feels like wonderful gift. I am even grateful for when the Sun sets early. Crystalline stars and shimmering Northern Lights appear closer in these long winter nights. This time of year, Orion is really a perfect friend. He keeps me company on dark lonely drives, sparkles handsomely above my doorstep, and after hanging out with him, I can still get to bed early!

This world provides us with much to be thankful for.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Our exhibit: “The Northwoods ROCKS!” is open through mid-March. Our Fall Calendar of Events is ready for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.