Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


TDRS-4 Mission Complete; Spacecraft Retired From Active Service

The Tracking and Data Relay Satellite 4 (TDRS-4) recently completed almost 23 years of operations support and successfully completed end-of-mission de-orbit and decommissioning activities. TDRS-4's operational life span was well beyond its original 10-year design.

Launched on March 13, 1989, from onboard Space Shuttle Discovery, TDRS-4 operated in geosynchronous (GEO) altitude at more than 22,000 miles above the Atlantic Ocean region. As part of the spacecraft's end-of-mission activities, its orbit was raised above the congested geosynchronous orbit.

An Artist Rendering of TDRS-4.
Credit: NASA

TDRS-4 was forced to retire after the loss of one of three Nickel-Cadmium (24 cell) batteries and the reduction in storage capacity for the two remaining batteries that power the satellite. Retirement for the satellite consisted of excess fuel depletion, disconnecting batteries, and powering down the Radio Frequency Transmitters and receivers so that the satellite is completely and permanently passive. This ensures the satellite will never interfere with other satellites from the radio frequency perspective.

This is the second retirement from within the fleet of TDRS. The fleet of seven remaining satellites operates through a supporting ground system and together they make up the Space Network (SN). The SN provides highly automated, user-driven services supporting customer spacecraft with tracking and data acquisition. The network supports a varied number of missions, including the International Space Station, Hubble Space Telescope, launch vehicles, and a variety of other science missions. The SN also provided primary communication support to the Space Shuttle Project.

"The Space Network spacecraft engineering and operations teams worked together very effectively to execute a practically flawless decommissioning of an incredible satellite," says Mike Rackley, SN deputy project manager at NASA's Goddard Space Flight Center, Greenbelt, Md. "TDRS-4 made great and important contributions to NASA's human spaceflight and science missions. We will certainly miss her."

This is the second end-of-mission execution for the fleet of aging first generation TDRS spacecraft. TDRS-4's retirement was preceded by TDRS-1, which was decommissioned and raised to its permanent orbit in June 2010.

A total of six first generation spacecraft were successfully placed into orbit from April 1983 through July 1995, of which four are still active. The spacecraft are approaching the end of their operational life span but they are supplemented by three, second-generation spacecraft.

Together they provide customers with global space to ground communication services.

To continue this critical lifeline, NASA has contracted Boeing to build three additional follow-on TDRS spacecraft, replenishing TDRS-1 and TDRS-4, and expanding NASA's communication services. TDRS-K is scheduled for launch in December of this year followed by TDRS-L in 2013 and TDRS-M in 2015.

The SN is managed by GSFC and its primary ground communications facility is located at the White Sands Complex in Las Cruses, NM. The Human Exploration and Operations Mission Directorate and the Space Communications and Navigation Program at NASA Headquarters fund NASA's Space Network.

Nicole Hagey and Dewayne Washington
NASA's Goddard Space Flight Center, Greenbelt, Md.

Dewayne Washington | EurekAlert!
Further information:

Further reports about: Active Agents Goddard Space Flight Center Greenbelt NASA Shuttle Space TDRS-4 spacecraft

More articles from Physics and Astronomy:

nachricht Gamma ray camera offers new view on ultra-high energy electrons in plasma
28.10.2016 | American Physical Society

nachricht Scientists measure how ions bombard fusion device walls
28.10.2016 | American Physical Society

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Prototype device for measuring graphene-based electromagnetic radiation created

28.10.2016 | Power and Electrical Engineering

Gamma ray camera offers new view on ultra-high energy electrons in plasma

28.10.2016 | Physics and Astronomy

When fat cells change their colour

28.10.2016 | Life Sciences

More VideoLinks >>>