Clusters Nebulae Galaxies

The Magellanic Clouds, our galactic neighbors

Three dish telescope under dark skies with large puffy white spot at center of sky and smaller haze to the upper left, the Magellanic Clouds.
The night sky from ESO’s Paranal Observatory in Chile, with the Large and Small Magellanic Clouds showcased at center. Image via Y. Beletsky/ LCO/ ESO.

Lucky Southern Hemisphere observers get to see something that many northerners never see: the Magellanic Clouds. The Large and Small Magellanic Clouds are satellite galaxies of the Milky Way. As some of the closest galaxies to our home galaxy, they stand out as big, misty blobs of light under dark skies. Scientists estimate the Small Magellanic Cloud contains around 3 billion stars, while the Large Magellanic Cloud houses some 30 billion stars.

History usually credits 15th-century Portuguese voyager/astronomer Ferdinand Magellan with “discovering” these hazy star-clouds. And, in later years, the Clouds became known by his name. But, in addition to Magellan, many early navigators used these two small galaxies to find their way across southern oceans. And they were always noticeable in the sky to the people of the Southern Hemisphere, and so they figured in early southern legends and myths.

The Magellanic Clouds from the Southern Hemisphere

If you want to see the Magellanic Clouds, you have to head south. They’re not visible north of about 17 degrees north latitude. If you are in the Southern Hemisphere, you can see these satellite galaxies any night of the year because they’re south circumpolar, that is, they’re close enough to the South Celestial Pole that they never set.

The Large Magellanic Cloud is one of the closest galaxies to us at about 160,000 light-years away. It’s about 40,000 light-years closer than the Small Magellanic Cloud.

EarthSky 2022 lunar calendars now available! They make great gifts. Order now. Going fast!

How to see the Magellanic Clouds

The Large Magellanic Cloud is easier to spot than the Small Magellanic Cloud, but they both require dark skies.

The Large Magellanic Cloud shines at magnitude 0.9. Keep in mind that it’s stretched out over an area of sky about 9 by 11 degrees. A star of that magnitude would appear very bright because of its pinpoint source of light, but for the Large Magellanic Cloud, its diffuse, spread-out light means it appears as a hazy smudge on the sky.

The Large Magellanic Cloud lies in both the constellations Dorado and Mensa. Draw a line from Sirius past the right side of Canopus to find it.

Star chart with stars in black on white, with one very large star.
The Large Magellanic Cloud is found in the constellations Dorado and Mensa. The nearby star is Canopus. Image via Wikipedia.

The Small Magellanic Clouds shines at magnitude +2. Its brightness is spread over about about 13 square degrees of sky. You can find it in the southeast corner of the constellation Tucana the Toucan.

Chart with four stars connected by lines and labels for Achernar to left, 47 Tucanae and Small Magellanic Cloud below.
Tucana the Toucan is a famous constellation for being home to two amazing deep-sky objects that can be seen without optical aid: the Small Magellanic Cloud and the globular cluster 47 Tucanae.

The Clouds in myth

In the Southern Hemisphere, Australian Aborigines, the Maori people of New Zealand and the Polynesian people of the South Pacific were familiar with both the Large and Small Clouds. They used them as navigational markers during their oceanic expeditions. They considered these hazy star-clouds predictors of the winds. The website OzSky.org explains:

Many tribes of Australian Aboriginals have ‘dreamtime stories,’ which they have passed down from generation to generation, to explain the universe as they perceive it. One such legend describes the Clouds as the campfires of an old couple, the Jukara. The Jukara relied on other star people to supply them with fish and lily bulbs caught in the Milky Way to survive. The old couple cooked the food over their campfire, which was the star Achernar. The Large Cloud represented the old man while the Small Cloud was the old woman.

Another myth comes from South Africa. The nearby constellation Mensa (“Table”) got its name from South Africa’s Table Mountain. One story says that the Large Magellanic Cloud is a puff of smoke from a pipe-smoking contest held on the mountain.

In history, Al Sufi, the Persian astronomer, described the Large Magellanic Cloud in his Book of Fixed Stars in AD 964. He called it Al Bakr, describing it as the White Ox of southern Arabia.

Desert landscape with road and car lights, arching Milky Way above with bright patch under.
View larger. | In this image from Paranal, Chile, you can see the large swath of our galaxy, the Milky Way. The dwarf satellite galaxy, the Large Magellanic Cloud, is underneath the arch. The Small Magellanic Cloud is to its upper right. Image via Yuri Beletsky/ ESO.

Science of the Magellanic Clouds

Henrietta Swan Leavitt – famous for her work on the Cepheid variable stars – studied the Large and Small Magellanic Clouds from Harvard College Observatory in Southern Peru. In the early 1900s, she published her work on variable stars in the Small Magellanic Cloud, famously showing the relationship between the periods (cycles) of the stars’ variability and their luminosities. Her study was titled 1777 variables in the Magellanic Clouds. The period-luminosity relationship later became a reliable gauge for astronomers trying to parse the riddle of star and galaxy distances.

Astronomers believe that the Large and Small Clouds formed around the same time as our Milky Way, some 12 to 13 billion years ago. Due to their repeated interaction with our larger Milky Way galaxy, it’s thought that great galactic tides might have caused their irregular shape.

The ongoing Dark Energy Survey found a dark stream of interacting matter between the Large and Small Magellanic Clouds. Simulations performed by a team of scientists at the University of Arizona suggested that the two galaxies might be interacting with each other and might eventually merge.

Whitish-blue oval in upper right and smaller oval of light at lower left in starfield.
The Large and Small Magellanic Clouds are irregular galaxies that belong to the Local Group. Image via ESO/ S. Brunier.

Bottom line: The Large and Small Magellanic Clouds are two of the closest galaxies to the Milky Way. They can be seen without optical aid from southern skies.

Posted 
December 8, 2021
 in 
Clusters Nebulae Galaxies

Like what you read?
Subscribe and receive daily news delivered to your inbox.

Your email address will only be used for EarthSky content. Privacy Policy
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

More from 

Larry Sessions

View All