How Far Is the Sun From Earth?
The Sun is about 93,000 miles (150 million kilometers) from our home planet Earth. When we ask :How Far Is the Sun From Earth? it is often easier to think of it in terms of time. It takes about eight minutes for sunlight leaving the Sun to reach the Earth and warm our faces. As the only inhabited world we know about, Earth is the only planet in our Solar System with oceans of liquid water. About 70% of Earth’s surface is water.
Table of Contents
So let’s delve further into how far the Sun is from Earth and how that impacts our daily lives.
Astronomical Unit
Scientists needed a way to track space distances, but writing out huge numbers gets confusing. So they decided to use Earth’s distance from the Sun as the standard unit of measure. And therefore, one Astronomical Unit (AU) equals about 93 million miles (150 million km), the average distance to the Sun from Earth.
Here’s a list of each planet’s distance to the Sun in astronomical units.
| Planet | Distance From The Sun in AU |
|---|---|
| Mercury | 0.39 |
| Venus | 0.72 |
| Earth | 1 |
| Mars | 1.52 |
| Jupiter | 5.2 |
| Saturn | 9.54 |
| Uranus | 19.2 |
| Neptune | 30.03 |
Neptune is 2,793,125,646 (4,495,100,000 km) from the Sun without using astronomical units. So you can see why it makes more sense to display such vast distances in AU.
And if you’re wondering just how far one astronomical unit is in real-time, here you go. It would take an average passenger jet 20 years to fly to the Sun from Earth. 20 years. Each way. And that’s if you’re traveling 400 miles per hour without refueling.
So hopefully, that gives you a bit of perspective about how far the Earth is from the Sun.
Earth’s Atmosphere
Our home planet has an atmosphere perfect for all types of beings to live and breathe. It’s comprised of nitrogen (78%), oxygen (21%), and other ingredients (1%). So unlike Mercury’s super-thin exosphere or Venus’ chokingly thick sulfuric cloud atmosphere, Earth’s atmosphere is ideally suited for life.
In addition, Earth’s atmosphere protects our world from space debris like meteoroids. Fortunately, most of them break up on entry before they can make it to Earth’s surface.
Neighboring Planets’ Atmospheres
On the other hand, Mercury’s proximity to the Sun means torrential solar winds rip around the planet. They whip helium and hydrogen up from the surface to build the atmosphere. But just as quickly, the same winds tear through the thin layers to destroy the very same atmosphere they help create.
As a result, meteoroids, rocks, and space debris pummel Mercury’s surface, leaving it even more pockmarked than its formation volcanoes did. The planet’s lack of atmosphere also gives it gigantic temperature swings. Daytime temps soar past 800℉ (426℃.) But nighttime temperatures plummet to devastatingly cold lows of negative 330℉ (-201℃.)
And then Venus is our next neighbor on the way to the Sun from Earth. It has such a thick atmosphere that the planet is a hellish hot fury. The thick swirling stew of clouds creates a runaway greenhouse effect that leaves Venus’ surface hot enough to melt lead.
So you can see from the examples of Earth’s closest planetary neighbors near the Sun that having these perfect atmospheric conditions means everything to life as we know it.
Orbital and Rotational Effects On Earth From the Sun
During our orbit around the Sun, Earth completes a full rotation every 23.9 hours. So it takes 365.25 days to circle our primary Star. And that extra quarter day is why our calendars have a leap day and year.
Once every four years, Earthlings add a day to our calendars to keep them consistent with our orbital journey around the Sun.
Orbital Eccentricity
Earth has a lop-sided, elliptical orbit. So that moves us closer to and further from the sun at different times. And it’s also backward from what you’d think.
For example, wintertime in the northern hemisphere is when the planet is at its closest position to the Sun. So that shows how close or far we are to the Sun doesn’t matter much to our weather. That seasonal difference comes from Earth’s tilt, which we’ll dive into later.
Perihelion and Aphelion
Earth’s orbit takes the planet closest to the Sun in early January. Then in July, it whips out to the farthest distance the Sun is from Earth.
- Perihelion (Closest) Distance To The Sun = 91,400,000 miles
- Aphelion (Furthest) Distance From The Sun = 94,500,000 miles
Especially when compared to Mercury and Venus, who are closer to the Sun, Earth’s three million-mile difference isn’t much. For example, Mercury’s orbital eccentricity creates a difference of around 15 million miles in how close it is to the Sun.
Temperature Effects: How Far Is the Sun From Earth?
It’s easy to think that Earth must be closer to the Sun in the summer months, and that’s why the weather gets so warm. But, while that thinking makes sense, it is wrong. Instead, Earth’s tilt is the reason we experience seasons.
Earth’s Tilt Toward the Sun
Earth has a 23.4-degree tilt on its axis of rotation with respect to Earth’s orbital plane around the Sun. And that tilt creates seasonal weather cycles.
As our planet orbits the Sun, the axis stays tilted in the same direction. As a result, different regions experience the Sun’s direct rays. So when the northern hemisphere tilts toward the Sun, it rides higher in the sky. And that means more significant solar heating, making it summer.
But at the same time, the southern hemisphere experiences less direct sunlight, making it winter. Every six months, the situation reverses. But interestingly, Spring and Fall mean the Sun heats both hemispheres more or less equally.
Earth’s Magnetosphere
The Sun’s very presence impacts our planet’s magnetic field. For example, Earth’s nickel-iron molten core combines with a rapid rotation to create a magnetosphere stretching tens of thousands of miles into space.
But then solar wind (charged particles ejected from the Sun) whips along and stretches the magnetic field into a teardrop shape. Next, those charged solar particles get trapped in the magnetic field, where they crash into air molecules above Earth’s magnetic poles.
And then, the air molecules start glowing and create aurorae. So Earth’s nighttime northern and southern light displays are solar-related. And what a treat for anyone who gets to experience their beauty!
The September 17, 2011 image below comes from the International Space Station near the Southern Indian Ocean.
Summary: How Far is the Sun From Earth?
Even though Earth is the third planet from the Sun, our primary star significantly impacts everything about our lives. For example, it influences our weather, creating seasons. In addition, the Sun affects our ocean currents and makes life possible.
Without the Sun, Earth would be an ice-coated space rock. The Sun’s magnetic field stretches across space to interact with and alter Earth’s magnetosphere. And the Sun’s winds bring atomic particles that interact with our atmosphere and magnetic field while surrounding Earth and other planets. As a result, the Sun and the solar systems planets have intertwined systems that scientists continue unfolding.