With its spectacular rings and brilliant yellow hue, one might argue that Saturn is the most beautiful planet in the Solar System. With so much mystery still surrounding what lies beneath its thick atmosphere, we’ll need to travel a considerable distance to discover what’s under there. First, we need to understand how far away Saturn is.
How Do We Measure Distance in Space?
When scientists talk about distance in space, they typically use one of three different measurements. What they use depends on how far the object is from Earth.
Miles (or Kilometers)
When we look at some of the closest celestial bodies to us on Earth, we still use the same miles or kilometers we use on Earth. Of course, even the nearest natural object to us, the Moon, is 238,900 miles (384,472 kilometers) away from us. All other objects are millions, if not billions of miles away.
Astronomical Units
To keep distances within the Solar System a bit more manageable, scientists began using the astronomical unit (AU) around the turn of the 20th century. At that time, one AU was roughly the distance from the center of Earth to the center of the Sun. Since 2012, the value has been standardized and is now fixed at exactly 149,597,870,700 meters.
Light Years
Light travels at a constant 186,282 miles per second (299,791 kilometers per second) in space, so we can use this value to calculate the distance between bodies. It doesn’t take light a terribly long time to pass through the Solar System, but we can still use light-years nonetheless. To put things in perspective, the nearest star to our Solar System is still 4.25 light-years away.
How Far Is Saturn From the Sun?
Before we look at Saturn’s relation to the Earth, we need to take a look at how the gas giant orbits the Sun. The planet revolves around our star from an average of 886 million miles (1.4 billion kilometers) away. That distance is 9.5 AU, meaning Saturn is nearly ten times further from the Sun than Earth is.
This is only an average because Saturn’s orbit is not a circle but somewhat elliptical in shape. As a result, there are times where Saturn is closer to the Sun than others.
When Saturn travels closest to the Sun, known as perihelion, it is still 839 million miles (1.4 billion kilometers) from its source of heat and light. That distance ends up being just over 9 AU.
On the other side, Saturn can be as far as 934 million miles (1.5 billion kilometers) away at its aphelion, or furthest point. At just over 10 AU, that means Saturn’s distance from the Sun fluctuates by a whole astronomical unit. That’s the distance the Earth is from the Sun!
How Far Away Is Saturn From the Earth?
It’s relatively easy to calculate Saturn’s distance from the Sun, but things get a little more complicated when we look at Saturn’s distance from Earth. Relatively speaking, the Sun is a fixed point in our Solar System, and everything within revolves around it.
Both Saturn and our Earth are hurtling around that star at break-neck speeds. Compared to Earth’s 67,000 miles per hour (107,800 kilometers per hour), Saturn moves at a measly 21,637 miles per hour (34,821 kilometers per hour).
Saturn’s orbit is also much larger than ours, taking 29.5 years to make one revolution. As hard as it may be to imagine, some of us wouldn’t even be a year old yet if we were born on the ringed planet.
These factors make it tricky to provide an average distance from the Earth to the Sun, but we can look at some extremes.
Earth and Saturn at Their Closest
In the incredibly rare instance that Earth is in its aphelion and Saturn is sitting in perihelion, these two planets would be the closest they will ever be. Even so, this distance is still 746 million miles (1.2 billion kilometers) away. That puts the Earth and Saturn almost exactly 8 AU apart.
In this scenario, and any time Saturn is very close to Earth, it does have a special glow in the sky. At that point, it’s brighter than all the stars as seen from Earth except Sirius and Canopus. The planet glows with an apparent magnitude of -0.55. It still loses out to the other planets and struggles to stand out against other stars.
Earth and Saturn at Their Farthest
When Saturn is far out in space on the other side of the Sun, the distance between the two planets increases considerably. Once these planets are the furthest apart they can possibly be, there’s a distance of 1.05 billion miles (1.70 billion kilometers) between them. That’s an equivalent of 11.36 AU.
Thus, these planets can vary as much as 312 million miles (502 million kilometers) from each other over the roughly 15 years it takes Saturn to make half a trip around the Sun. At such a distance, when not hidden behind the Sun, Saturn’s apparent magnitude drops to a +1.17.
How Many Years Would It Take To Get to Saturn?
Given both objects are moving so fast through space, it takes some serious calculating to ensure you don’t miss your mark. Even the smallest error can send a spacecraft right past the planet.
Fortunately, four spacecraft have made the journey to the ringed giant thus far. Travel time for Pioneer 11 back in 1979 took six and a half years. Voyagers 1 and 2 made the trip in three years and two months and four years consecutively. Cassini in 2004 took six years and nine months to arrive.
NASA’s New Horizons probe flying at 36,000 miles per hour (57,936 kilometers per hour) didn’t visit Saturn but crossed its orbit in just two years and four months. These times are significantly different due to each craft’s trajectory and the type of engine used at the time.
For humans that have only managed to travel the 238,900 miles (384,472 kilometers) to the Moon, a trip to Saturn is no small feat. Even when the two are closest together, you’re still looking at traveling nearly 750 million miles (1.2 billion kilometers) just to get there.
Since a manned craft has to sustain life, it must travel at significantly slower speeds. It’s estimated that, with current technology, the mission would take eight years just to voyage one way.
Once we’ve figured out how to travel the stars at the speed of light, we’ll be able to make the trip in just 80 minutes. Although, once we’ve arrived, there wouldn’t be a hard surface to stand on.
How Long Does It Take for Light To Reach Saturn?
As you might guess, Saturn gets the majority of its light from our Sun. From Saturn’s distance of 9.5 AU, it wouldn’t look much bigger than the other stars in the sky. Sunlight would be 90 times dimmer than on Earth.
For light to travel from the Sun to Saturn at 186,282 miles per second (299,791 kilometers per second), it would take 79 minutes to get there. Compare that to the roughly eight minutes it takes that same light to reach the Earth.
The next closest star, Proxima Centauri, is 4.2 light-years away.
Final Thoughts
Saturn may be a planetary gem, but at its distance from Earth, it looks like nothing more than a pale glow in the night sky. Even the fastest spacecraft to date took well over two years to get there. Still, it doesn’t take much magnification to capture Saturn’s unique rings in the perfect photograph.