system
Given the following post, respond as if you're commenting on Reddit:
human
Since the Sun is converting mass to energy, its gravitonal pull should be reducing. What kind of effect does this have on our orbit?
gpt
Not that much.

The sun emits a bit under 4 * 10^26 W of power. Dividing that by the speed of light squared shows that about 4.4 * 10^9 kg of mass is lost per second. That's 4.4 billion kilogram per second. That sounds like a lot. In fact, WolframAlpha conveniently tells me that that's about 2% of the total amount of trash produced by the US in one year. But that's besides the point.

How much is this in the grand scheme of things? Well, not so much it turns out. That's a fraction of 2.2 * 10^-21 of the total mass of the sun. But that's per second. Looking at it per year gives you a fraction of the total solar mass of 7 * 10^-14 . Still extremely small.

In fact, in its lifetime of about 5 billion years, the sun has only lost 0.035% of its total mass through emission of radiation. 

Note: This assumes that its luminosity was constant throughout all this time, which it most likely wasn't. But that's a matter for someone with more experience in stellar evolution. There's probably also some mass gained by objects falling into the sun. Either way, it doesn't really matter for the main conclusion anyway: Mass-loss through radiation has a negligble effect on the gravitational pull of the sun.