How Far Is Uranus From the Sun, And How Long Would It Take to Get There?

Uranus is one of the most mysterious and inaccessible planets in the Solar System. Since its discovery in 1781, this blue ice giant has captivated astronomers from all over the world but it remains poorly understood due to its great remoteness and lack of terrestrial technology. All our knowledge about this planet is limited to data from the robotic Voyager 2 mission, the Hubble telescope, and several ground-based observatories.

How far away is Uranus from the Sun and Earth, how long does it take to get to Uranus, will we ever reach it again to reveal all its mysteries and is it worth it? You will find the answers to these questions below.

How Far Away Is Uranus From the Sun?

This ice giant is one of the four outer group planets and the seventh planet from the Sun, located between Saturn and Neptune. Uranus’s average distance from the Sun is approximately 1.8 billion miles, 2,986 billion km or 19.2 au. This means that Uranus is about 19.2 times farther from the Sun than Earth.

(Author’s note: one astronomical unit (au) was adopted by the IAU (International Astronomical Union) in 2012 as a unit of distance in astronomy and equals the average distance from the Earth to the Sun, which is precisely 149,597,870,700 metres.)

But why are we talking about average distance? The thing is, Uranus, like all the planets in the solar system, constantly moves in an elliptical orbit around the Sun. As a result, it can be closer or further from the star at different points in its orbital cycle.

When this planet is at perihelion (closest point to the Sun), its distance from the Sun is about 1.7 billion miles (2,735 billion km or 18.28 au). At aphelion (the farthest point from the Sun), the ice giant is 1.87 billion miles (3 billion km or 20 au) away from the star. Light travels this distance in about 2 hours 40 minutes, and the fastest man-made object that exists on Earth today, the Parker Solar Probe, would take a little less than six months.

To discover Uranus’s current distance from the Sun, you need to know the parameters of its orbit. These data were first calculated in 1783 by the French astronomer Pierre-Simon Laplace, but over time, discrepancies between the calculated and observed positions of the planet were revealed. After Laplace, many more astronomers and physicists tried to establish the orbital parameters and physical characteristics of this planet, but the most accurate data were obtained by the Voyager 2 spacecraft, which flew past the ice giant in 1986.

How Far Is Uranus From Earth?

Earth is the third planet from the Sun and is separated from Uranus by approximately 1.6 to 2 billion miles (2.57–3.22 billion km, 17.7–21.52 au). You can see the exact data on How Far Away is Uranus from Earth now on TheSkylive website.

You may ask, how can Uranus distance from Earth be greater than its distance to the Sun if our planet is closer to Uranus than the Sun? Once again, the rule of orbital planetary motion comes into play.

Distance from Uranus to Earth can be greater than its distance to the Sun at moments when the Earth and Uranus are at opposite points in their orbits relative to the Sun. This occurs when the ice giant is at aphelion, and our planet is at perihelion. During such periods, the line connecting our planet and the ice giant passes through the Sun, and, therefore, the total distance between Earth and Uranus through the Sun will be greater than the direct Uranus’s distance from the Sun.

How Long Did It Take to Get to Uranus? 

For Voyager 2, the journey from Earth to Uranus took 9.5 long years. So far, this probe is the only man-made terrestrial object to reach the ice giant. This was almost half a century ago when space technology was still poorly developed. Voyager flew at no more than 34,000 miles per hour, which is why the journey took so long.

If the Parker Solar Probe, which has a top speed of nearly 400,000 mph, were to fly to the ice giant today, it could theoretically reach the planet in 200 days. However, this calculation is very conditional. The thing is, Parker’s speed is so high mainly because it is caught in the powerful gravity of the Sun. During the journey to the ice giant, the probe does not need to fly close to the Sun, so this speed would be unattainable.

Will We Ever Reach Uranus Again?

NASA and ESA have such plans. Their joint research mission, called The Uranus Orbiter and Probe, is planned for the next decade. Ice giants are now considered the most common type of exoplanet, accelerating the need for further study of ice giants in the solar system. Although Neptune is considered to be of great scientific value, Uranus was given preference for logistical and financial reasons.

The new journey to the blue giant will take about 12–15 years, and will depend on the launch date, which will determine the closest distance from Uranus to Earth. When planning a mission to the outer planets of the solar system, finding the ideal window can take up to 100 years, since one orbital revolution of Uranus around the Sun equals 84 Earth years.

The mission plan intends to use a SpaceX Falcon Heavy rocket to launch the orbiter, which will then perform a gravity assist manoeuvre around Earth and then a gravity assist manoeuvre around Jupiter (as was the case with Voyager 2) to gain greater speed and save fuel for the scientific phase of the mission. The scientific phase will last 4.5 years and will include multiple flybys of each of the ice giant’s main moons, as well as descending an atmospheric probe to study the planet’s atmosphere. The Uranus Orbiter and Probe was originally scheduled to launch in 2031-2032, but NASA delayed the date due to declining plutonium production, so the mission is likely to launch in the mid-to-late 2030s.

How Long Would It Take Humans to Get to Uranus?

The answer to this question remains hypothetical since no astronauts have visited other planets yet. But one thing is clear: a spacecraft with a crew on board will have to move slower than an automatic probe in order to protect fragile human bodies from overloads.

To date, the highest speed achieved by humans in space is the Apollo 10 mission in May 1969 — 24,791 miles per hour. Interplanetary missions, such as those to Mars or Uranus, will require reaching escape velocity, which is slightly higher — 25,053 mph.

However, the exact speed that the spacecraft will reach to overcome the Uranus distance from the Earth will depend on many factors, including the spacecraft mass, the amount of fuel, the flight path, and the use of gravity assist manoeuvres. And the mass of the ship and fuel must definitely be large if we want to bring the astronauts back. For this, the ship must be equipped with advanced life support systems and carry fuel for the return journey, since there will be nowhere to get it on the ice giant. And such a ship is almost ready. This is Space X Starship.

Thus, if travel time to Uranus for a light probe takes 12-15 years, a manned spaceflight will last at least 3 years more.

Would You Age Slowly on Uranus Compared to the People on Earth?

Everyone remembers the episode from one of the best space movies Interstellar, when the astronauts land on the planet Miller, where time moves in slow motion — one hour on its surface is equal to seven Earth years. Returning back to the ship, they discover that their colleague, Dr. Romilly, has noticeably aged.

Does this mean that once we get to Uranus, where one year equals 84 Earth years, we will age 84 times slower than people on Earth and will never see our loved ones again? We reassure you, no.

Time for a person on ice giant will flow the same way it does on Earth. A year on this planet equals 84 Earth years because the distance of Uranus from the Sun is greater and its orbit is longer, so the blue giant takes more time to make one revolution around the Sun. However, these factors do not in any way affect the speed of time.

Time is a homogeneous and continuous value that is measured the same throughout the universe, except for the effect of gravitational time dilation predicted by Einstein’s general theory of relativity. It is believed that this effect occurs near massive gravitational objects such as black holes. The stronger the gravity of an object, the stronger the time dilation. Planet Miller in Interstellar was very close to the Gargantua black hole, so time passed slower there. At the moment, the closest black hole to the solar system is approximately 1000 light years away, and its gravity cannot influence us in any way. As for the gravitational fields of the Solar System planets, they are too weak to cause significant time dilation; the error margin is measured in fractions of a second and can be neglected in everyday life.

So, it does not matter how far is Uranus from the Earth; for people, time there will still flow the same as it does on Earth. A second will remain a second, a minute will remain a minute, an hour will remain an hour, and a year will remain a year.

Step By Step Closer to the Clue

Uranus remains one of the most intriguing study objects in our solar system. Travelling to this ice giant is not just a technical challenge, but also a step towards expanding the boundaries of our understanding of the Universe. With the development of technology, we can expect that someday the question of how long would it take to get to Uranus will cease to worry humanity and it will confidently make its path to the threshold of this distant world, opening new horizons for the next generations of researchers.

References and Additional Info:

• Uranus Orbiter and Probe
  https://smd-cms.nasa.gov/wp-content/uploads/2023/10/uranus-orbiter-and-probe.pdf
• Scale of the Solar System
  https://www.nasa.gov/wp-content/uploads/2015/01/yoss_act1.pdf
• Parker Solar Probe
  https://science.nasa.gov/mission/parker-solar-probe/
• 35 Years Ago: Voyager 2 Explores Uranus
  https://www.nasa.gov/history/35-years-ago-voyager-2-explores-uranus/
• How Long Would It Take to Cruise the Solar System?
  https://www.watchmojo.com/articles/how-long-would-it-take-to-cruise-the-solar-system
• Time Dilation: Why Does Gravity Slow Down The Flow Of Time? https://www.scienceabc.com/nature/universe/time-dilation-why-does-gravity-slow-down-the-flow-of-time.html