The picture, known as Pale Blue Dot (above) depicts our
planet as a nearly indiscernible speck roughly the size
of a pixel. 

On Valentine’s Day, 1990, 3.7 billion miles away from the sun,  
the Voyager 1 spacecraft looked back at our solar system and
snapped the first-ever pictures of the planets from its perch at
that time beyond Neptune. This is the last image Voyager 1 ever
beamed back after which the cameras were turned off to save
power and memory.

Artist impression of Voyager-1.

On this day in 1957, the Soviet Union inaugurated the "Space Age"
with its launch of Sputnik, the world’s first artificial satellite. The spacecraft, named Sputnik after the Russian word for "satellite,"
was launched at 10:29 p.m. Moscow time from the Tyuratam launch
base in the Kazakh Republic. Sputnik had a diameter of 22 inches
and weighed 184 pounds and circled Earth once every hour and 36 minutes. Traveling at 18,000 miles an hour, its elliptical orbit had
an apogee (farthest point from Earth) of 584 miles and a perigee
(nearest point) of 143 miles.

Visible with binoculars before sunrise or after sunset, Sputnik transmitted radio signals back to Earth strong enough to be
picked up by amateur radio operators. Those in the United States
with access to such equipment tuned in and listened in awe as the
beeping Soviet spacecraft passed over America several times a day.

The Soviet Union inaugurated the “Space Age” with its launch
of Sputnik, the world’s first artificial satellite, on October 4, 1957.

The spacecraft, named Sputnik after the Russian word for “fellow traveler,” was launched at 10:29 p.m. Moscow time from the
Tyuratam launch base in the Kazakh Republic.

Sputnik had a diameter of 22 inches and weighed 184 pounds and
circled Earth once every hour and 36 minutes. Traveling at 18,000
miles an hour, its elliptical orbit had an apogee (farthest point from
Earth) of 584 miles and a perigee (nearest point) of 143 miles.

A Soviet technician works on Sputnik in 1957.

From the Atlantic Missile Range in Cape Canaveral, Florida,
the U.S. unmanned spacecraft Explorer 6 was launched into
an orbit around the earth. The spacecraft, commonly known
as the “Paddlewheel” satellite, featured a photocell scanner
that transmitted a crude picture of the earth’s surface and
cloud cover from a distance of 17,000 miles. The photo,
received in Hawaii, took nearly 40 minutes to transmit.

Released by NASA in September, the first photograph ever
taken of the earth by a U.S. satellite (below) depicted a
crescent shape of part of the planet in sunlight. It was
Mexico, captured by Explorer 6 as it raced westward over
the earth at speeds in excess of 20,000 miles an hour. 

First satellite image of the Earth from space, taken by
Explorer 6 in 1959.

Explorer 6 Satellite (Reconstructed Replica) at the National Space Museum.

Communications satellite Telstar 1 was launched atop a Thor-Delta rocket on July 10, 1962. It successfully relayed through space the
first television pictures, telephone calls, and telegraph images,
and provided the first live transatlantic television feed. Telstar 2
launched May 7, 1963. Telstar 1 and 2, though no longer
functional ,still orbit the Earth today.