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Here's how you can spot Saturn's moons: Titan, Rhea, Dione and more

Not all of Saturn’s moons are visible in space; however, some can be bright enough to be traced by a reliable telescope from Earth.

BY MAHALEKSHMI P

PUBLISHED 59 MINUTES AGO

Digital improvement of an image from NASA containing Saturn and few of its Moons. (Representative Cover Image Source: Getty Images | Photo by Roberto Machado Noa)

Saturn is the planet in our solar system with the most moons - 146 known natural satellites. However, not all of them are visible, and only seven can be spotted through a reliable telescope from Earth. The easiest visible moon is Titan, according to BBC Sky at Night Magazine. The good news for amateur astronomers is that they do not need the Hubble Space Telescope to view these natural satellites.

Few sights in the solar system are more strikingly beautiful than softly hued Saturn embraced by the shadows of its stately rings (image Source: NASA/JPL-Caltech) — Few sights in the solar system are more strikingly beautiful than softly hued Saturn, embraced by the shadows of its stately rings (Representative Image Source: NASA/JPL-Caltech)

Before we can track Saturn's moons, we must find where Saturn is, which is visible to the naked eye, but the rings require a basic telescope. According to TimeandDate, the best time to observe it is around its Opposition, when it is directly opposite the Sun. The planet looks brightest during this event, rising near sunset and setting near sunrise, being visible all night long. To observe the steady glow of the planet and its moons, we can use modern astronomy apps or software like Stellarium.

Titan passes in front of Saturn in this image from NASA's Cassini spacecraft (Cover Image Source: NASA) — Titan passes in front of Saturn in this image from NASA's Cassini spacecraft (Representative Image Source: NASA)

The giant Titan can be spotted easily

Titan's brightness can reach up to +8.4. It is bigger than Mercury, with a diameter of 3,200 miles, as per BBC Sky at Night Magazine. This moon is only beaten by Jupiter’s Ganymede in the ranking scale, placing it second, and is the only moon with a substantial atmosphere. While it is bright enough to be caught by a pair of binoculars, a telescope will further enhance your experience. That being said, looking at it through a telescope, you'll be able to see its nitrogen-rich cloud tops and not Titan’s surface. It completes an orbit in about 16 days and is about five of Saturn's ring diameters away from the planet at its farthest.

The line of Saturn rings disrupts NASA's Cassini spacecraft's view of the moons Tethys and Titan (Representative Image Source: NASA Image and Video Library | NASA)

Rhea, Dione, and Tethys are next in line

These moons are quite accessible and often visible through a 3-inch refractor telescope. Rhea is the second-largest of Saturn's moons and has a magnitude of +9.7. It takes 4.5 days to complete an orbit and is often seen around two ring diameters away from the planet. Tethys shines at a magnitude of +10.3 and is located around one ring diameter away from Saturn. Completing an orbit in just 1.9 days, Tethys is known for a vast canyon stretching three-quarters of the way around itself and two co-orbital moons, Telesto and Calypso. Dione has a visual magnitude of +10.4 and is the densest of Saturn's moons. This indicates its possession of a large rocky core. The satellite orbits in 2.7 days, and is around 1.5 ring diameters away from the planet.

Illustration of the moons of Saturn as it is surrounded by a large system of varied satellites. (Representative Image Source: Getty Images | Photo by MARK GARLICK/SCIENCE PHOTO LIBRARY)

Spotting Iapetus and Enceladus can be a challenge

The brightness of Enceladus is around +11.8, while that of Iapetus varies dramatically between +10.1 and +11.9, and you'll need a 6-inch telescope to see it at its darkest. While it's the third largest of Saturn's satellites, Iapetus is also the most distant of the planet's main moons. The most inclined of the inner satellites, its 79-day orbit takes it out to 12 ring diameters away from the host planet.

This view of Saturn's moon Enceladus was taken by NASA's Cassini spacecraft (Cover Image Source: NASA-JPL)

Mimas, the faintest moon

Mimas takes the crown of the faintest moon with a magnitude of just +12.9. You'll need a 6-inch telescope and perfect viewing conditions without any light pollution to spot Mimas.