The distance between Jupiter and Io varies because Io's orbit is elliptical, not circular.

Here's a breakdown:

* Average Distance: The average distance between Jupiter and Io is about 421,700 kilometers (262,000 miles).

* Closest Approach (Perijove): At its closest point, Io can be as close as 350,000 kilometers (217,000 miles) to Jupiter.

* Furthest Point (Apojove): At its furthest point, Io can be as far as 480,000 kilometers (300,000 miles) from Jupiter.

So, depending on where Io is in its orbit, the distance between the two can fluctuate significantly.