# Why is the Sun's Luminosity not equal to the Zero Point Luminosity?

I was doing some research and found that the zero-point luminosity was $$L_\odot = 3.75\times 10^{28}$$, while the sun's reported luminosity was $$L_{Sun} = 3.828\times 10^{26}$$, according to Wikipedia. Why isn't it the same value? Doesn't the symbol $$\odot$$ represent the value of our sun?

Furthermore, when Googling the Luminosity of the sun, it gives $$1L_\odot$$, which suggests that $$L_{Sun} = L_\odot$$ when it is evidently not. What's going on here? I'm very confused.

For background, I have little to no background knowledge of astrophysics, and I'm trying to learn about it.

Thanks.

• Could you link/clarify what the 'zero point luminosity' is? I'm not familiar with the concept myself. Also units should always be added for any physical quantities. – AtmosphericPrisonEscape Aug 16 at 11:26
• @Anurag Do you mean the zero point of the absolute magnitude scale? – SpaceBread Aug 16 at 12:59
• $L_{\odot}$ is the bolometric luminosity of the Sun. I don't know where you get $3.75 \times 10^{28}$ W from? – Rob Jeffries Aug 16 at 14:11
• What units are these two values in? Are they both in Watts? If not, they could be equivalent, but using different unit systems. – HDE 226868 Aug 16 at 15:34