Browse Resources by Year

2005 – Communications Satellites Overview

Currently, the Satellite Database maintained by Analytical Graphics, Inc. (AGI) shows that 536 active communications satellites are in orbit. Of these, 298 are in a geostationary (GSO) or geosynchronous (GEO)…

2005 – Human Settlements

Surface systems are those systems that operate on the surface of a planet. Current operational surface systems include the NASA Jet Propulsion Laboratory (JPL) Mars Rovers, Spirit and Opportunity. These robots were launched in June and July 2003, with the purpose of understanding the history of water on Mars.

2005 – Bigelow Space Stations

A privately financed company based in Las Vegas, Nevada, Bigelow Aerospace is licensing technology from NASA to build an inflatable in-space platform that could enable a number of on-orbit applications. Bigelow’s prototype inflatable platform was launched July 12, 2006, aboard a Russian- and Ukrainian-built Dnepr rocket, launched from Russia’s Yasny Launch Base by International Space Company (ISC) Kosmotras.

2005 – ISS

The largest in-space platform ever constructed is the International Space Station (ISS). “Led by the United States, the ISS draws upon the scientific and technological resources of 16 nations: Canada, Japan, Russia, 11 nations of the European Space Agency [Belgium, Denmark, France, Germany, Italy, the Netherlands, Norway, Spain, Sweden, Switzerland, and the United Kingdom], and Brazil,” according to NASA.

2005 – QZSS

Japan is developing the Quasi-Zenith system, a regional augmentation of the GPS signal, with a 2008 planned launch.

2005 – Galileo

Europe launched the first test satellite in the Galileo system in December 2005.

2005 – GPS

The U.S. NAVSTAR (Navigation Signal Timing and Ranging) GPS constellation consists of ## active and ## spare satellites in MEO. According to the DoD, the fundamental concept of GPS is to use simultaneous distance measurements from ## satellites to compute the position and time of any receiver. The GPS signal is available without cost to users around the world and has spawned many commercial applications.

2005 – Ground Networks

Ground station infrastructure provides command, control, tracking, and telemetry systems for launch vehicles, satellites, and other platforms. Worldwide tracking systems operated by government agencies support launch command and control. Satellite ground stations are operated either by commercial or government entities; their components include the large satellite receivers used to transmit and receive signals to and from satellites on orbit for the purpose of communication, navigation, or data transfer.

2005 – Spaceports Overview

Major United States and international launch sites, according to Teal Group and Astronautix are listed in Exhibit 2m. These launch sites are both commercial and government operated.

2005 – Satellite Orbits

As geostationary (GSO) satellites remain in an essentially fixed position relative to the ground at all times, they can communicate with fixed ground stations continually. Medium Earth orbit (MEO) and low Earth orbit (LEO) satellites appear to “fly by” overhead and have a shorter communication window for a given station, from ten minutes for a LEO satellite to two hours or more for a MEO satellite. Satellites in highly elliptical orbits may be in communication with a fixed ground station for up to eight hours.