What Is the Distance Between the Planets in Different Units

The distances between planets aren’t fixed: each planet orbits the Sun at its own speed, so the separation between two worlds constantly changes. Here are the key figures in kilometers and miles, with average distances to the Sun and the minimum and maximum possible distances between neighboring planets.

Why the distance between planets isn’t a fixed number

Each planet follows an elliptical orbit around the Sun, and all move at different speeds. That means the distance between, say, Earth and Mars, varies depending on where each one is in its orbit. It can range from 54.6 million km when they’re aligned on the same side of the Sun, to over 400 million km when they’re on opposite sides.

That’s why, when talking about the “distance between planets,” it’s more useful to look at each planet’s average distance to the Sun, which is a stable and comparable value.

Table of distances between planets and the Sun

This is the average distance of each planet to the Sun, in kilometers and miles:

• Mercury: 57.9 million km (36 million miles)
• Venus: 108.2 million km (67.2 million miles)
• Earth: 149.6 million km (93 million miles)
• Mars: 227.9 million km (141.6 million miles)
• Jupiter: 778.5 million km (483.8 million miles)
• Saturn: 1,434 million km (890.8 million miles)
• Uranus: 2,871 million km (1,784.8 million miles)
• Neptune: 4,495 million km (2,793 million miles)

This Earth-Sun distance of 149.6 million km is so important it has its own name: the astronomical unit, the standard yardstick for distances within the solar system.

Distance from Earth to each neighboring planet

What’s usually more interesting in practice is how far it is from Earth to another planet, not to the Sun. These are the approximate minimum and maximum distances:

• Earth-Mercury: between 77.3 and 222 million km (48 to 138 million miles)
• Earth-Venus: between 38.2 and 261 million km (23.7 to 162 million miles)
• Earth-Mars: between 54.6 and 401 million km (33.9 to 249 million miles)
• Earth-Jupiter: between 588.5 and 968.1 million km (365.7 to 601.4 million miles)
• Earth-Saturn: between 1,195 and 1,658 million km (742.8 to 1,030.4 million miles)

The big difference between the minimum and maximum explains why space missions choose very specific launch windows: taking advantage of the moment when two planets are closest saves fuel, time, and money.

The closest planet to Earth isn’t always the same one

There’s a popular idea that Mars is Earth’s “neighbor,” but a 2019 study recalculated average distances across all possible orbital positions and reached a different conclusion: on average, Mercury is the planet that spends the most time being closest to Earth, followed by Venus. This happens because Mars, although it sometimes gets extremely close, spends most of its time on the other side of the Sun, while Mercury and Venus, having smaller orbits, maintain shorter average distances more consistently.

How long it would take a spacecraft to travel these distances

The figures in km and miles take on new meaning when translated into travel time. A typical spacecraft travels at about 40,000-60,000 km/h once outside Earth’s orbit:

• To the Moon (384,400 km): about 3 days
• To Mars (minimum 54.6 million km): between 6 and 9 months
• To Jupiter (minimum 588.5 million km): between 4 and 6 years
• To Neptune (minimum 4,300 million km): more than 12 years

If you’d rather think of it with an everyday vehicle instead of a spacecraft, there’s a curious comparison about how long it would take to reach Mars at car speed, which puts these figures into a much more down-to-earth perspective.

Why miles and kilometers are used depending on context

NASA and most English-speaking space agencies publish distances in miles, while the ESA and European agencies use kilometers. To quickly convert between the two units:

• 1 km = 0.621371 miles
• 1 mile = 1.60934 km

With distances as large as planetary ones, a small rounding error in conversion can translate into thousands of kilometers of difference, so it’s best to always use the exact figure rather than a quick mental approximation.

Distances between the outer planets

Starting from Jupiter, the distances between neighboring planets also grow significantly:

• Jupiter-Saturn: about 655 million km (407 million miles) on average
• Saturn-Uranus: about 1,437 million km (893 million miles) on average
• Uranus-Neptune: about 1,624 million km (1,009 million miles) on average

These figures show a clear pattern: the farther from the Sun, the more spread out the planets are from each other. The solar system isn’t uniformly distributed; it “opens up” as you move away from the center.

Putting these figures into human perspective

Numbers like “4,495 million km” are hard to imagine without a point of reference. If we scale the solar system so the Sun were a basketball, Earth would be a pinhead about 28 meters away, and Neptune would be almost 850 meters away, nearly ten soccer fields in a row. To better understand why these magnitudes defy our everyday intuition, it’s worth reviewing the distances in the universe that the human mind can’t imagine.

Frequently asked questions

What is the distance between Earth and Mars in km and miles?

It varies depending on both planets’ orbital positions: the minimum is about 54.6 million km (33.9 million miles) and the maximum can reach 401 million km (249 million miles). The approximate average distance usually hovers around 225 million km (140 million miles).

Which planet is closest to Earth?

According to a 2019 study that averaged all possible orbital positions over time, Mercury is on average the closest planet to Earth, followed by Venus, although Mars can get extremely close at specific moments.

How many km are there between Earth and Jupiter?

The distance ranges from 588.5 million km (365.7 million miles) at the closest point to 968.1 million km (601.4 million miles) at the farthest, depending on where both planets are in their orbits.

Why does the distance between planets constantly change?

Because each planet orbits the Sun at a different speed and over a different period. Since they don’t move in sync, the separation between any two planets increases and decreases cyclically as they approach or move away from each other in their respective orbits.

How do you convert kilometers to miles over such large distances?

Multiply the figure in kilometers by 0.621371 to get miles, or multiply miles by 1.60934 to get kilometers. For planetary distances, it’s best to use these exact factors, since a small rounding error can create differences of thousands of kilometers.