First of all, thanks!
About the round subject, it's true that the way that it was written could lead to a misunderstanding of the task so I have changed it.

Also, I will keep the sugestion in mind for what will most likely become the second part of this kata, harder and definitely more interesting!

All of these, (Saturn, Mercury and Uranus), were being ignored, but I fixed it.

Similar issues here:

input:
['Earth>>>>', '<<Saturn', 'Venus>', 'Mars>>>>', '<<<<Asteroid', '<<<Mercury', 'Blackhole', '<<<Uranus']
output: 
['Blackhole'] should equal ['Mercury', 'Blackhole']

Mercury should have gone out of orbit

input:
['Neptune', '<<<<Asteroid', '<<<<Saturn', 'Mars>', 'Venus>', '<Asteroid', 'Mercury>>', '<Asteroid', 'Uranus>']
output: 
[] should equal ['Uranus']

Uranus should have gone out of orbit

• done
• done for all languages

Changed to margin of error on perceived time per JohanWiltink's comment

In languages where a bool is an int, bools should be treated as integers, e.g. [2,True,False] -> '11'.

Language?

Fixed it

Fixed.

O(1)

Thanks, Ciprian Amza :-)

Your solution wouldn't pass now anymore.

1.Fixed

2. Yes, description updated.