# Could our solar system exist 100x bigger?

1. Jul 28, 2014

### louisbaron

Imagine somewhere far within the solar system there was an exact copy of our solar system (Proportional). But the overall proportion was increased by 100. Imagine a supergiant star/sun with a proportional planets to that of our solar system. So in theory the people would look like giants in relation to our body size. My question is would this be possible? And is it likely for this to exist within the solar system.

2. Jul 28, 2014

### Staff: Mentor

No, this is not possible. The increased size and mass have profound effects on the star and planets. For one, the Sun would be so massive that it would only survive a few million years instead of the roughly 8-10 billion years it will last now. Also, the planets simply cannot grow to 100x their current size and retain a similar makeup. A rocky planet 100x the size of the Earth would be larger and more massive than Jupiter (if by size you mean diameter). Jupiter would gain so much mass that it would become a star larger and more massive than the Sun.

It's also not possible that "giants" exist 100x larger than humans due to scaling issues. See the following articles:
http://en.wikipedia.org/wiki/Square-cube_law#Biomechanics
http://en.wikipedia.org/wiki/Allometry

3. Jul 28, 2014

### louisbaron

So I could assume small fractional increases in overall size could be acceptable for the solar system to be stable?

4. Jul 28, 2014

### phinds

Possibly, but the problem you run into on these "scaling up/down" things that some people just don't seem to think through is that some things act based on a CUBE (the volume/mass of a sphere for example) and some on a SQUARE (the gravitational attraction based on distance). Scaling is thus not as trivial as just changing everything's size, you also have to adjust distances but not by the same scale factor.

5. Jul 28, 2014

### Pds3.14

100-times-scaled planets would be problematic. Earth, for example, would have 3 solar masses and, before its inevitable collapse into a white dwarf or neutron star or some other mysterious very dense object occured, have 100 G of gravity on its surface. a 100-times-scaled human wouldn't be able to survive lying down sleeping in 1 G, let alone standing up and walking around in 100.

The core pressure of Earth would be something like 3.5 Petapascals initially. That is far too high for any kind of matter to avoid compressing, which would further increase the gravity, further increasing the pressure, etc, until something exploded and the remains collapsed.

Jupiter would not only be a star, it would be too massive to be a star, at a density like that, Jupiter would collapse until fusion occured at the center, then violently explode as a chain reaction caused the 1000-solar-mass monster to blow off its outer layers in a supernova-like fashion.

A 100-times-scale sun would tend to either collapse or explode, although it might be possible that it would form a blackhole star or some other immensely massive and exotic object.

Naively, a star that massive would be a bomb. It would be presumed to have a lifespan of about 5 minutes and 15 seconds. Of course, the speed of light would restrict that, but you get the idea. Even the 100x Jupiter would have a lifespan of only 316 years.