The question of how much the Sun would cost provides a compelling framework for a thought experiment in science and economics. Since celestial bodies are not commodities, any valuation must be purely conceptual, based on the material and energy they represent. By treating the Sun as either a massive collection of raw elements or an immense, long-term power generator, we can arrive at a theoretical price tag. This exercise combines astronomical facts with current industrial commodity prices and energy market rates to find a figure that is truly astronomical.
Defining the Sun’s Physical Inventory
To calculate the Sun’s worth as a material object, we must first define its physical inventory, starting with its immense mass. The Sun accounts for over 99.8% of the entire mass of our solar system, with its total mass resting at approximately 1.989 x 10^30 kilograms. This colossal figure is the primary metric for valuing its constituent gases.
The composition is overwhelmingly simple, consisting almost entirely of two elements: 74% hydrogen and 24% helium by mass. The remaining 2% comprises all the other heavier elements, such as oxygen, carbon, and iron. Even this small 2% represents a mass far greater than the total mass of all the planets combined.
Calculating the Cost Based on Raw Elements
Valuing the Sun as a pile of industrial gases allows for the most literal price calculation. The Sun contains approximately 1.472 x 10^30 kilograms of hydrogen and 4.774 x 10^29 kilograms of helium.
For a conceptual bulk price, we assign a conservative industrial value to these gases. Hydrogen, which has a market price ranging from $1.50 to $15 per kilogram, is valued at a low-end industrial rate of $2 per kilogram. Helium, a scarcer gas used in cryogenics and manufacturing, is valued at approximately $101 per kilogram.
Multiplying these masses by their respective prices yields a staggering figure. The hydrogen component alone is worth approximately 2.94 x 10^30 dollars (2.94 nonillion). The helium component, despite its smaller mass, adds about 4.82 x 10^31 dollars to the total. The Sun’s theoretical raw material cost sits at an approximate total of 5.1 x 10^31 dollars, or 51 nonillion dollars.
Calculating the Cost Based on Energy Output
A far more compelling valuation assesses the Sun based on its function as an enormous power source. Its luminosity, the total power output, is a constant 3.828 x 10^26 Watts, generating 3.828 x 10^26 Joules of energy every second. To translate this power into a monetary value, we calculate the total energy produced over its remaining lifespan.
The Sun has five billion years remaining before core hydrogen fusion ceases. Over this time, it will produce roughly 1.67 x 10^37 kilowatt-hours (kWh) of energy. We assign a price using a conservative industrial rate of $0.10 per kWh, a typical bulk wholesale rate for electricity.
This calculation results in a total energy value of approximately 1.67 x 10^36 dollars, expressed as 1.67 undecillion dollars. This valuation is orders of magnitude higher than the raw material cost, illustrating the difference between a resource’s raw material value and its functional output. This figure represents the conceptual price a civilization might pay to capture and utilize all of this energy, such as with a hypothetical Dyson Sphere megastructure.
The Impossibility of the Astronomical Transaction
The price tag for the Sun, whether using the 51 nonillion dollar raw material cost or the 1.67 undecillion dollar energy value, highlights the practical impossibility of the transaction. The Sun’s highest valuation is vastly larger than all the wealth that currently exists on Earth. The total estimated value of all financial and real assets worldwide is only around 471 trillion dollars, a tiny fraction of the Sun’s price.
Beyond the financial hurdle, the transaction is legally and philosophically impossible. The 1967 Outer Space Treaty explicitly prohibits any nation from claiming ownership or sovereignty over the Sun, Moon, or any other celestial body. The Sun is considered the common heritage of mankind, and no legal framework exists to facilitate its sale. The astronomical figures underscore that the Sun’s true value lies in its existence as a life-sustaining constant, which remains priceless.