Gazing Toward Our Galaxy’s South Window into Intergalactic Space
When you gaze toward the bright star Fomalhaut, located in the constellation Piscis Austrinus (the Southern Fish), you’re looking toward what’s called our galaxy’s south window. In other words, you’re looking away from the flat plane of our Milky Way, where most of our galaxy’s stars reside. Essentially, you’re gazing toward the direction of one of the galaxy’s poles.
Why Find Fomalhaut?
When you look at Fomalhaut — sometimes called the Loneliest Star — you are looking about 90 degrees away from the plane of our galaxy’s equator. Since most of the galaxy’s stars are concentrated in its flat disk, the region of the sky around Fomalhaut appears relatively empty to the naked eye.
But beyond Fomalhaut, and beyond the stars of the Milky Way that lie in this direction, there is vast space between galaxies — intergalactic space. By looking toward Fomalhaut, you are essentially looking out through the galaxy’s south window into the depths of the cosmos.
The Milky Way’s South Galactic Pole
Our Milky Way galaxy is shaped like a round, flat pancake. When you look toward Fomalhaut, you are looking away from this pancake-like disk and out through the galaxy’s south window. This means you face the star-packed plane of the galaxy’s disk head-on, away from it, and into intergalactic space — the realm where other galaxies reside.
If you want the exact location of the south galactic pole, it lies just east of Fomalhaut, in the faint constellation Sculptor. You can refer to the accompanying star charts below to help find it.
How to Find Fomalhaut
Fomalhaut is a very noticeable star precisely because it sits in a region of the sky that contains few stars bright enough to be seen with the naked eye. This scarcity of nearby bright stars is why Fomalhaut is often dubbed the “Loneliest Star.”
If you’re unsure which star is Fomalhaut, a useful guide is the Great Square of Pegasus. This large asterism appears in the southern sky to overhead around 7 to 8 p.m. local time in late November and early December. The Great Square really does form a large square shape, with four medium-bright stars marking its corners.
To find Fomalhaut, draw an imaginary line downward from the two westernmost stars of the Great Square — and you will arrive at Fomalhaut. Between these stars and Fomalhaut, you can also see the golden-hued planet Saturn glowing in 2025. Refer to the chart below for visual guidance.
From the Southern Hemisphere
If you’re observing from the Southern Hemisphere, the Great Square of Pegasus appears to the north around 9 to 10 p.m. local time during late November and early December. In this case, draw a line upward from the two westernmost stars of the Great Square to locate Fomalhaut. Keep an eye out for golden Saturn between them as well.
Bottom Line
Use the Great Square of Pegasus as your celestial map to locate Fomalhaut. Once you’ve found this bright, lonely star, you’re well on your way to looking through our galaxy’s south window into the vast expanse of intergalactic space.
For more sky events and observing tips, visit EarthSky’s night sky guide.
https://earthsky.org/tonight/looking-out-galaxys-south-window/