Musk posted on X that the scale of the Earth's economy is less than one trillionth of the "K2 economy." K2 refers to a Type II civilization in the Kardashev scale, which is a civilization capable of harnessing all the energy output of its star. Musk implies that, in terms of energy, all current human economic activities are negligible compared to a civilization that can control an entire sun.

The Kardashev scale was proposed by Soviet astronomer Nikolai Kardashev in 1964, classifying civilizations based on their energy consumption: Type I can utilize all the energy from its home star, approximately 10^16 to 10^17 watts; Type II can harness the total output of a star, with the sun's total power being about 3.8×10^26 watts; Type III can utilize the energy of an entire galaxy. Carl Sagan later provided a continuous calculation formula, which indicates that humanity is currently at about 0.73, not yet reaching Type I civilization.

This figure withstands scrutiny. Global primary energy consumption is about 620 exajoules per year, equivalent to an average power of about 2×10^13 watts, or approximately 20 terawatts. Dividing this by the sun's total power of 3.8×10^26 watts results in about 5×10^-14, roughly one two-hundred-trillionth, which is an order of magnitude smaller than Musk's claim of "less than one trillionth." Even the total solar energy reaching Earth, about 1.7×10^17 watts, accounts for only about one two-billionth of the sun's total output.

K2 has entered Musk's capital narrative. At the end of April, a proposed SpaceX compensation plan discussed externally linked rewards to human civilization levels: achieving Type I civilization corresponds to $100 trillion, and Type II civilization corresponds to $1 quadrillion. Musk responded that if humanity could "approach K2," it would be a good deal, but "by then, we won't use dollars as currency, only mass and energy."

SpaceX has brought this narrative into the secondary market. In February 2026, SpaceX acquired xAI entirely in stock, with a post-merger valuation of $1.25 trillion. On June 12, SpaceX went public on NASDAQ at $135 per share under the ticker SPCX, raising $86 billion, far exceeding Saudi Aramco's record of $29 billion in 2019, becoming the largest IPO in history. It closed on the first day at $161, up 19%, with a market capitalization of about $2.1 trillion. Musk holds about 42% of the shares and controls 82% to 85% of the voting rights through Class B super-voting shares. In 2025, SpaceX had total revenue of $18.7 billion and a net loss of $4.94 billion; Starlink revenue was $11.4 billion with about 10 million users; xAI revenue was $3.2 billion, with a simultaneous loss of $3.2 billion.

In market mechanics, buyers are institutions and retail investors betting on the long-term narrative of "space plus AI," while sellers are early shareholders cashing out during the IPO and funds taking profits after the listing. After reaching a high of $202 on June 16, SpaceX's stock price fell significantly; at one point, its price-to-sales ratio exceeded 100 times, nearly double that of the highest-valued company in the S&P 500. The core supporting valuation is the orbital data center: using nearly uninterrupted solar energy in space to power AI computing. Musk's Tesla, SpaceX, and xAI have also formed a chip joint venture, Terafab, aiming for a 2-nanometer process with an initial capacity of 100,000 wafers per month. Beneficiaries include Musk's ecosystem providing launches, energy, and chips, while those under pressure are secondary market investors needing to digest extremely high valuations based on long-term narratives.

Source: Public information