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The Planets AlignedUpdated 2 years ago

The Planets Aligned is wall art that presents a model of our solar system showing the planets as they are positioned relative to each other and the sun on a given date.

By combining the latest data from NASA's Jet Propulsion Laboratory with increasingly accurate algorithms to calculate the position of planetary bodies built over centuries, this solar system print provides a unique and inspiring fingerprint of your special moment in time.


The model shows the heliocentric view the Universe, that is one in which the sun it at the center of the solar system and all the planets orbit around it. This model, sometimes called "Copernican Heliocentrism" or the "Copernican model" of the solar system was controversially proposed by Nicolaus Copernicus in the 16th century. This proposal was extremely controversial at the time as it contradicted the accepted earth-centric model of the Universe.

During this time, an astronomer called Tycho Brahe was creating the most accurate compilation of naked eye measurements of planetary positions previously produced and even he remained unconvinced, instead proposing a model where some planets orbited the sun, but the earth remained at the center of our solar system. However, the data he collected would prove invaluable. In the early 17th century astronomer named Johannes Kepler, who had previously worked for Brahe, analysed his data and realized that the planetary orbits where not perfectly circular, but instead, elliptical, and was able to build on that insight to create his laws of planetary motion - a set of rules that were able to accurately predict planetary positions. 

At the same time, based on his telescopic observation of the phases of Venus, Galileo Galilei presented evidence supporting the Copernican model. He was famously summoned to Rome and ordered by the church to recant this view and deny the Copernican model, which for a time the church banned, but the evidence could not be ignored and as technology advanced, so it has proven the Copernican model.


In the time since Kepler set the foundation with his Laws of Planetary Motion, algorithms have been designed and translated for early and now modern computers to predict the past and future orbital trajectories on a solar system scale. Given a starting location and a trajectory of a solar system body around the sun, these algorithms can predict the past and future travel of those bodies for centuries to come. An "ephemeris" (plural "ephemerides") is the name given to these sets of coordinates and trajectories used as inputs to these calculations.

Calculating the position of the planets as they travel through our solar system is a complex process. Not only do the planets orbit under the influence of the gravity of the sun, they are also effected by the gravity of each other, the moons and even asteroids throughout the solar system. In order to ensure that the future calculations are precise as possible, updated ephemerides - these positions and trajectories - provided through observation are continually fed back into the system.


Jet Propulsion Laboratory (JPL) is a NASA research and development center whose primary function is the construction and operation of planetary robotic spacecraft. In order to land a rover on Mars, it helps to know where Mars is! So as part of their mission they run the HORIZONS System, an online system to generate precise and up to date object positions and trajectories of the orbital bodies used to compute their position.

JPL has been revising and updating their ephemerides for over 20 years, providing data not only for the 8 solar system planets, but also almost 200 moons, over 3500 comets and almost 800,000 asteroids! While the precision of the data used to land a rover on Mars is far beyond what we might need to render a solar system model on the scale that we do, we live in an age where we hold previously unimaginable computing power in our pockets, so we can use that to generate pixel accurate models for The Planets Aligned, for memorable dates in the past and for centuries to come.


In 2005, the discovery of Eris, a dwarf planet 27% more massive than Pluto led to the International Astronomical Union (IAU) to define the term "planet" formally in 2006. That definition excluded Pluto and reclassified it as a dwarf planet. While a source of significant controversy at the time, we like to think of it not as losing a planet, but of gaining a new set of previously ignored dwarf planets! You can choose to render Pluto on our star map, along with some of the other Dwarf planets: Eris, Ceres, Haumea and Makemake.

The complete list of planets and dwarf planets we present in our print is as follows (dwarves marked with an asterisk): Mercury, Venus, Earth, Mars, Ceres*, Jupiter, Saturn, Uranus, Neptune, Pluto*, Haumea*, Makemake*, Eris*


While the angle of each of the planetary bodies relative to the sun is exact, the distances from the sun to the individual bodies has been scaled down to for the sake of the print. Equally, the individual planet sizes have also been reduced. It would be impossible to render a star map otherwise and our scaled model still provides an accurate and unique position of that object on your chosen date.

It is difficult to comprehend, let alone describe, the vastness of our solar system but to better understand the miles of wall that might be needed to present a model without compressing these distances, you may watch this informative video:

We are proud of the accuracy of the print and hope that this piece of art inspires. Please contact us if you have any questions!

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