# What would g be on jupiter?

1. Jul 2, 2011

### scotty_le_b

I was wondering what would g equal on jupiter if you could stand on its surface? I wrote a computer programme (my 1st one) to work g out anywhere and when i plugged in the numbers for earth it gave me 9.799 which is correct and for jupiter it gave me 24.778 but when I looked it up I kept finding values nearer 28. I had the mass of jupiter as 1.8987e27 and the radius of jupiter as 7.1492e7. I had already set G to be 6.67e-11 and the programme uses the formula g=(G*m)/r^2. Have I done anything wrong or could it just be different values for the mass of jupiter and its radius?

Thanks
p.s. I realise that you could never stand on the surface of jupiter :)

2. Jul 2, 2011

### Fightfish

There is nothing wrong with your values, just that what you have obtained is the g at the equatorial surface of Jupiter (7.1492e7 is the equatorial radius). Planets are not perfectly spherical, they are slightly flattened at the poles (and thus 'widest' at the equator). The larger values of g that you have found are likely to have been calculated using the mean radius of Jupiter instead, which is smaller than the equatorial radius.

The disparity is less significant on earth due to its smaller mass.

3. Jul 2, 2011

### scotty_le_b

Oh that makes sense.
Thank-You

4. Jul 2, 2011

### Subductionzon

And that is not g for the surface of Jupiter, at least not in the same sense as the surface of the Earth, something that you can stand on. That is the g force you would feel if you were in a gondola under a balloon floating at the gaseous surface of Jupiter. Now somewhere there is a solid surface of Jupiter, but there is not enough data to say how big it is or what it is. At least to my knowledge. Hmm. Google Search time.