What Would our Solar System be like if our Sun were Half its Mass?

Either way you look at it, it would be like terrible, horrible, no good, very bad badness.

But to be a bit more specific, let’s talk about what would happen if our Sun—the Sun as it actually exists—suddenly decreased in mass, plummeting from 1 solar to mass to a mere .5 solar masses. In order to understand what impact this decrease would have, you need to have a basic understanding of how mass is related to gravity. Essentially, an increase in mass means an increase in gravity, while a decrease in mass means a decrease in gravity. So if the Sun spontaneously lost half its mass (gasp, shudder, the horror!) then its gravitational pull on Earth would lower. Since the Sun's pull would be weaker, our orbit would increase.

To read the full article, see: http://www.fromquarkstoquasars.com/what-would-our-solar-system-be-like-if-our-sun-were-half-its-mass/