import pandas
planets = ['Mercury', 'Venus', 'Earth', 'Mars']
distances_raw = [ 0.4 , 0.7 , 1, 1.5 ]
masses_raw = [ 0.055, 0.815, 1, 0.107]
distance = pandas.Series(distances_raw, index = planets)
mass = pandas.Series(masses_raw, index = planets)
print(distance)
# Mercury 0.40
# Venus 0.70
# Earth 1.00
# Mars 1.50
# dtype: float64
print(distance.index)
# Index(['Mercury', 'Venus', 'Earth', 'Mars'], dtype='object')
print(distance[distance < 0.8])
# Mercury 0.4
# Venus 0.7
# dtype: float64
print('------')
print(distance/mass)
# Mercury 7.272727
# Venus 0.858896
# Earth 1.000000
# Mars 14.018692
# dtype: float64