The world's leaders in space explorations - United States, Russia and China - are reportedly sending weapons and setting up military power in outer space. A new war, this time taking place outside of the Earth, could be brewing, according to the Scientific American.

The news outlet said that active satellites numbering close to 1,300 have been orbiting the Earth's vast atmosphere. Used for navigation, weather observation and communication, these satellites may also be a tool for "planetary surveillance."

While down on the ground, military weapons and powerful rockets are being developed, manufactured and primed for destroying enemy spacecraft, according to Reuters.

The United States leads as the country with the "most heavily armed space power," but Russia and China are not far behind. These countries are said to be developing ways to destroy U.S. satellites, said Director of National Intelligence James Clapper in his testimony in Congress in March, according to Bloomberg.

Destroying a satellite is possible in many ways, and it could involve a simple tampering of its mechanisms and antennas, or destabilizing this from its orbit. Delicate parts, such as sensors, microwaves and radio could be jammed, while transmissions may hijacked by those on the ground.

Space wars have been a threat since the 1950s, but it's a lot more complicated today as scientific and commercial progress in space, which also benefits different nations, makes outer space more viable.

There are also no rules, no guidelines, nor watchdogs against these military space powers.

"The bottom line is the United States does not want conflict in outer space," said Assistant Secretary Frank Rose, who has been part of the diplomatic efforts, via the Scientific American report. "But let me make it very clear: we will defend our space assets if attacked."