Mary 30 Toth, age 13, of Newport News, Virginia, for her question:

Does the earth shine on the moon?

For the first time in history, we have seen glorious photographs of our earth taken from out in space. The experience transports us to a realm of cosmic beauty, far beyond our struggles and strifes. It proves that, seen from out there, our home planet truly merits a glamorous place in the heavens. This enormous experience has no price tag. Per¬haps those who complain about the cost of the space program have failed to let those portraits bestow their stupendous message.

Bit by bit; the space program has extended our minds to behold our world in its proper place in the universe. We know now that looking up is really looking out at the vast cos¬mos around our globe on every side. We shared with the lunar astronauts the experience of landing on another world. Prom there also, one looks up and out into the vast reaches of space. And from there, looking back toward home, the earth shines big and bright in the lunar sky.

Sunlight falling on the earth is reflected back into space, some of it shining on the moon   just as moonlight falls on the earth. The earth is much brighter and 13 times big¬ger than the moon in our skies. The details of its beauteous face appear in a changing patchwork of jewel tone colors. However, the earth can be seen only from the side of the moon that is turned towards us and it does not rise and set every day in the lunar skies. Phases of sunlight and shadow creep over its gorgeous face, but the sequence of phases are the. reverse of the lunar phases we see from the earth.

The earth appears bigger and brighter because it actually is bigger and brighter   ¬and also, more colorful than the moon. The other differences are related to the motions of the earth and the moon. The earth rotates every 24 hours, spinning a complete view around the globe toward the moon every day. The moon rotates once while it orbits the earth, keeping the same side turned toward us. For this reason, the earth is never seen in the skies from the other side of the moon.

The fact that the moon fixes one side towards us, also fixes the position of the earth in the lunar sky. 47e see this one half as a golden disk. From the center, the earth remains more or less directly overhead. As one approaches the rim, it hangs lower and  still lower in the sky. The orbiting, moor creates the lunar phases we see from the earth because it changes our positions in relation to the sun. When it passes between us and the sun, its far side is in daylight and we see the New Moon. Then the Full Earth appears in the lunar sky. The moon sees the New Earth when we are closer to the sun and the sun shines on the Full Moon.

Astronomers have known these lunar facts for ages. But those photographs taken from the actual vicinity of the moon added another dimension, far more vivid than words or figures. A  book called 'This Island Earth' will help you to grasp it. Its code number is NASA SP 250. If you let it, its breath taking space portraits of our planet will trans¬port your heart to the heavens.