In 1977, two space probes lifted off from Earth on a mission
to the outer reaches of the solar system. Voyager 1 and 2 each
carried a unique item among the usual scientific instruments: a
golden record filled with pictures, sounds, songs, and languages
from around the world. The record was made of gold wrapped
around a disc of copper, since recordings made on metal plates
last longer and remain clearer than recordings made on ordinary
plastic. The record, packaged with a needle and a power source
to act as a basic record player, was designed to last for millions of
years in outer space.
The golden record was meant to be a quick guide to the Earth
for anyone or anything that came across Voyager 1 or 2 during their
journeys across the stars. The pictures on the record were supposed
to show what kinds of plants and animals lived on Earth, what the
Earth itself looked like, and what humans were like at all ages and
What Is the
Periodic Table?
the periodic table
in all countries. Other images included snowflakes, houses, an X-
ray
of a hand, diagrams of a woman giving birth, crocodiles, and
even an astronaut in space. The golden record also included “greetings
from Earth” in 55 different languages, 90 minutes of music
from around the world, and noises such as the sound of a chirping
cricket, the wind in a storm, and laughter. The cover of the golden
record was marked with simple math symbols and drawings that
explained what the record was and how it should be played.
Although it did not make it onto the golden record, there is one
picture that could have explained all the materials that make up the
people, animals, plants, rocks, oceans, and the rest of Earth. That
picture is the periodic table of the elements.
The periodic table answers the question “what are things made
of?” If it sounds like something a small child might ask, it is good
to remember that the answer was not obvious for thousands of
years of human history. Before the question was answered, the
periodic table did not exist, even in the imaginations of the most
thoughtful scientists.
Today, we know that things are made of elements. An element
is a basic building block of matter. Matter is the material that makes
up everything in the universe, from stars to spacecraft to golden
records. The periodic table is a list of all the basic building blocks
of matter that are found naturally, along with some building blocks
that have been created in the laboratory here on Earth.