Urge President Obama to Move Us Toward a World Free of Nuclear Weapons
The world has changed dramatically since the end of the Cold War. In the 21st century, nuclear weapons are a global security liability, not an asset. Tell the president to reduce the threat from nuclear weapons.
Has anyone ever been hit by a piece of falling
piece of space debris? Find the answer to
this question and other interesting facts about space debris re-entry in our Space Age Trivia section.
TacSat-4
Photo of TacSat-4's communications antenna courtesy of the Naval Research Laboratory.
The Tactical Satellite-IV (TacSat-4) is a U.S.
Navy-led experimental spacecraft.
Positioned in a highly-elliptical, 4 hour-period orbit, it is designed
to allow deployed troops to communicate from obscured or high-latitude regions under
radio-interference conditions using equipment they already have. The theaters over which it can dwell can be
changed in 24 hours via an orbital change. The program also further develops
the U.S. military’s goal of developing satellites that are relatively light and
low-cost, and can be rapidly deployed in response to an urgent need.