Jay Hugo, age ll, of Portland, Me., for his question:
Which is the tallest peak on the moon?
The lunar Apennines tower an estimated height of l8,500 feet above the flat floor of Mare Imbrium. The best measurements we have of the lunar mountains tells us that Mons Huygens is l8,044 feet high. Mons Hadley is l4,763 feet and Mons Bradley is l4,l07 feet.
For ages, Mount Everest has been our planet's tallest peak but this was not proved until the l840s. It is not easy to measure the exact height of our mountains here on the earth and it is even harder to measure the mountains of the moon for they are thousands of miles away. Our eyes can spot some of the shadowy dips and the high, sunlit plateaus. Telescope pictures reveal details of the craters and ridges, and space probes and lunar landings have gathered and sent even finer details of the barren scenery.
We know that the moon has its share of mountains. The main ranges on our side of the moon were observed ages ago, and some were named for mountains of the earth. We can estimate the height of certain lunar ranges from the length of the shadows they cast but this does not give us the exact height of the peaks. The exact height of our own highest mountains was not known until a little more than a century ago.
The earth's peaks begin to crumble even as they grew, and we do not know how tall a mountain could become on our planet. The moon is a little more than one fourth the size of the earth, and we might expect our highest ranges to be four times taller than the mountains of the moon. However, though we do not know its exact height, we can be sure that the tallest lunar peak will out top our loftiest Mount Everest.
Our winds and weather forever wear away our lofty peaks, but the moon has no weathery atmosphere. Its mountains grow and stand there, tall and untouched through the ages. For two earth weeks they stand in the bitter cold under the stars of the lunar night sky. As the moon rotates they turn to scorch in two earth weeks of lunar daylight ¬but in the airless silence there are no storms to lash their slopes and towering peaks.