Need help converting values regarding Jupiter's mass, and moons.

[nukeman]

Here is my problem. I have charted out the data points of one of Jupiter's moons, and have concluded for this example, a value of: P(in days) of 7, and a (height of the peaks above zero) of 4

Now, here is what I am having trouble doing:

"Convert P and a to years and AU. Then, convert a to KM"

Can anyone help me with this?

I know that one J.D = 0.00096 = 142,984 km

?

 

[nukeman]

Anyone? :)

Thanks

Here is my problem. I have charted out the data points of one of Jupiter's moons, and have concluded for this example, a value of: P(in days) of 7, and a (height of the peaks above zero) of 4

Now, here is what I am having trouble doing:

"Convert P and a to years and AU. Then, convert a to KM"

Can anyone help me with this?

I know that one J.D = 0.00096 = 142,984 km

?

 

[qraal]

Anyone? :)

Thanks

Strange question. Convert to years and AU, then to km. Why? You already have it in JD. So multiply by that conversion factor you've quoted to get km. Though diameters are a bit odd, since it's usually in radii as that's what plugs into the equations.

As for conversion to 'years', which year do they mean? A standard Julian year is 365.25 days, but there's several other years that get used to, such as the Gaussian.

An AU is presently defined as 149,597,870.7 km. You'll see 149,597,870.691 km get quoted, but that's a bit too precise for the error bars. Hopefully someone has seen fit to tell you what AU value to use.

 

[RocketSci5KN]

Your question is not very clear... What does 'height of the peaks above zero' mean? What is the '4' ? Inches, miles, lightyears, cubits? JD=jupiter's diameter? Is the orbital radius of this moon 4 * JD ?

 

[pmacias]

Sure, I can help you with this! To convert P to years, we need to use the formula P(yrs) = P(days)/365.25, since there are 365.25 days in a year (accounting for leap years). So in this case, P(yrs) = 7/365.25 = 0.01914 years.

To convert a to AU (astronomical units), we need to use the formula a(AU) = a(KM)/149,597,871, which is the distance between the Earth and the Sun in kilometers. So, in this case, a(AU) = 4/149,597,871 = 2.674e-8 AU.

Finally, to convert a to kilometers, we can simply use the conversion factor you provided: 142,984 km per J.D. So, a(KM) = a(J.D.) * 142,984 = 4 * 142,984 = 571,936 km.

I hope this helps! Let me know if you have any further questions.