Hello everyone! This will be the first in a series of posts highlighting the shapes we see in the night sky. It feels appropriate beginning with Ursa Major. While you’ve probably heard of this well-known constellation, you’re probably more familiar with the famous Big Dipper. So why are we talking about bears instead of ladles? Well, while Ursa Major is a constellation, the Big Dipper is an asterism within Ursa Major. What is an asterism? It is defined as a recognizable pattern of stars that is not one of the 88 modern constellations recognized by the International Astronomical Union (1), or, more simply put, a constellation that is not a constellation. Seems arbitrary? Well, it kind of is. Over half of the modern constellations were cataloged by the Greco-Egyptian astronomer Ptolemy (c. 100 - c. 170) in his work The Almagest from Mesopotamian, Greek, and Egyptian sources (2). This is merely a drop in the cosmic bucket of starlore from around the world, and we must always be careful to not fall for what such a Western-centric pitfall when studying the night sky. While I will be focusing on the modern constellations in these posts, I will not be limiting my scope in telling the stories associated with them. Astronomy is universal, and my goal is to show how throughout our history, we humans have looked up and told stories about what we saw.
Firstly, where can one even find Ursa Major? The constellation exists in the northern celestial hemisphere, and it is circumpolar for viewers north of the 35th parallel north, meaning the constellation never sets below the horizon (3). Those viewers south of the Tropic of Capricorn are able to see the constellation’s southernmost stars. If you are in the northern hemisphere, look north! As Ursa Major is the third largest constellation in the night sky, it is difficult to miss (4). Your best bet is to find the seven bright stars of the Big Dipper asterism, which I’m sure you’ve found without even trying before. With a reference, you should not have a difficult time finding the fainter stars that make up the rest of the constellation.
My favorite part about Ursa Major is that if you can find it, you can find our North Star, Polaris! First, find the Big Dipper and go to the side of the ladle farthest from the handle. Forming this side are two stars: Dubhe, from the Arabic “Ad-Dubb” for “the bear,” and Merak, from the Arabic “Al-Maraqq” for “the loins” (5). Take the length between these two stars and from the tip of the ladle’s bowl measure five of these lengths following the direction of the line made by Merak to Dubhe. Around the end of these five lengths, you will find Polaris! If you are having trouble visualizing this, see Figure 2. Ursa Major’s proximity to Polaris is the reason it doesn’t ever dive below the horizon for much of the Northern Hemisphere.
The significance of this cosmic pointer lies far beyond an interesting stargazing trick. For enslaved Black Americans, it meant the possibility of self-liberation and a life free from the evils of chattel slavery. The Drinking Gourd, as referenced in the folk song Follow the Drinking Gourd, is another name for the Big Dipper. The song is said to have been sung along the Underground Railroad as a coded guide on how to reliably find North (6). Fugitives from slavery traced the line made by Merak and Dubhe to find Polaris and followed it northwards towards Canada, where slavery had been abolished. Since the Drinking Gourd never sets, it can serve as a guide all year long. Alongside the primary message to follow the Drinking Gourd, the song also encoded an escape route up the Tombigbee River in Alabama and Mississippi and then down the Tennessee River to where it meets the Ohio River in Kentucky. Enslavers in America who sought to steal everything from the people they captured and enslaved could take neither the night sky nor the knowledge of its movements ingrained in the human psyche. This same knowledge guided humanity in wayfaring and navigation for millennia. Many of us today equate outer space with a vague idea of freedom. We must be mindful that, to Black Americans fleeing from slavery, the cosmos had the potential to provide real freedom from a heinous institution. (7)
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