The quasar 3C 273 has a luminosity about 25 trillion times that of the Sun. Assuming this is the Eddington limit, what is the minimum mass of the active galactic nucleus (stated in solar masses)?

Question

Quizplus · Accepted Answer

The Eddington limit is the maximum luminosity a body (like a star or a quasar) can achieve when there is equilibrium between the gravitational force pulling material inwards and the radiation pressure pushing material outwards. The formula for the Eddington luminosity (L) is given by $L = 1.26 \times 10^{31} \times \frac{M}{M_{\odot}}$ watts, where $M$ is the mass of the object in solar masses ($M_{\odot}$). Rearranging this formula to solve for $M$, and given that the luminosity of 3C 273 is about 25 trillion ($25 \times 10^{12}$) times that of the Sun ($L_{\odot} \approx 3.828 \times 10^{26}$ watts), we find that the mass of the active galactic nucleus must be significantly high to support such luminosity, leading to the conclusion that the minimum mass is in the order of hundreds of millions of solar masses, specifically around 850 million solar masses.

The Quasar 3C 273 Has a Luminosity About 25 Trillion