GOES-NO/P/Q — The Next Generation
Table of Contents

Table of Contents

The Mission ----------------------------------------------------------------------------------------- 1

Mission History ------------------------------------------------------------------------------------- 2

The Spacecraft -------------------------------------------------------------------------------------- 4

The Instruments ------------------------------------------------------------------------------------- 6

Imager ------------------------------------------------------------------------------------------ 7

Sounder ----------------------------------------------------------------------------------------- 8

Space Environment Monitor ----------------------------------------------------------------- 9

Solar X-Ray Imager ------------------------------------------------------------------------- 12

Instrument of Opportunity ----------------------------------------------------------------- 14

Search and Rescue-------------------------------------------------------------------------------- 15

Cospas-Sarsat System ---------------------------------------------------------------------- 15

Launch and Orbit --------------------------------------------------------------------------------- 17

Coverage Area ------------------------------------------------------------------------------------ 20

Image Navigation and Registration ------------------------------------------------------------ 21

Data Products and Services --------------------------------------------------------------------- 22

Communications ---------------------------------------------------------------------------------- 25

Sensor Data ---------------------------------------------------------------------------------- 26

Data Collection System -------------------------------------------------------------------- 26

LRIT/WEFAX ------------------------------------------------------------------------------- 27

Emergency Managers Weather Information Network ---------------------------------- 27

Command and Data Acquisition ---------------------------------------------------------- 27

NASA’s and NOAA’s Roles and Support Systems------------------------------------------- 28

NASA Support Facilities ------------------------------------------------------------------- 28

NOAA Support Facilities ------------------------------------------------------------------ 28

Launch Support ------------------------------------------------------------------------------ 29

Prior Spacecraft ----------------------------------------------------------------------------------- 29

GOES History ------------------------------------------------------------------------------- 29

GOES Spacecraft Contractors ------------------------------------------------------------------ 32

Acronyms and Abbreviations ------------------------------------------------------------------- 33
1The Mission

Cospas is an acronym for the Russian words Cosmicheskaya Sistyema Poiska Avariynich Sudov,

which mean “Space System for the Search of Vessels in Distress.”

The impressive imagery of cloud cover produced by the Geostationary Operational Envir

on-mental Satellites (GOES) series, as viewed from orbit high above the Earth, has be

come a highlight and staple of television weather forecasts. Forecasting the approach of

severe storms for more than 25 years, GOES has remained an essential cornerstone of weather

observations and forecasting.

The GOES system of weather satellites provides timely environmental information to meteorologists and their audiences

alike—graphically displaying the intensity, path, and size of

storms. With El Niño and La Niña affecting people worldwide, GOES images have been featured on the covers of the

international press, appearing in National Geographic, Der

Spiegel, and Life magazines. GOES images have become so

common that many people think of hurricanes in terms of the

popularized images of Hurricanes Hugo, Andrew, and Floyd.

The GOES program, begun in 1974, is a joint development

effort of the National Oceanic and Atmospheric Administration (NOAA) and the National Aeronautics and Space Administration (NASA). NASA provides launch support and designs, engineers, and procures the satellites. After a satellite is

launched and checked out by NASA, it is turned over to NOAA for its operations. NOAA also

determines the need for satellite replacement.

GOES spacecraft operate as a two-satellite constellation in geosynchronous orbit above the

equator and observe 60 percent of the Earth. They measure the Earth’s atmosphere, its surface,

cloud cover, and the solar and geosynchronous space environment and provide a platform for

the Imager, Sounder, Solar X-Ray Imager (SXI), and space environment monitoring instruments. The system also supports land- and ocean-based Data Collection Platforms (DCPs),

transmits Low Rate Information Transmission (LRIT)/Weather Facsimile (WEFAX) and imaging and sounding data between Earth terminals, relays Emergency Managers Weather Information Network (EMWIN) broadcasts, and participates in the international Cospas-Search and

Rescue Satellite-Aided Tracking (Sarsat) system.

NOAA and NASA are developing a new series of geosynchronous meteorological satellites that will

continue and enhance the current five-satellite GOES series. The new satellite series, designated

GOES-NO/P/Q, has several new top-level capabilities. These capabilities include the WEFAX service changing from an analog to a digital LRIT format; expanded measurements for the space environment monitoring instruments; a new dedicated channel for the EMWIN service; and most importantly, a more stable platform for supporting improved Imager, Sounder, and SXI instruments.
2 Mission History

Geosynchronous satellites orbit

the Earth from west to east at an

altitude of approximately 22,240

miles or 35,790 km and at a

speed that keeps them fixed over

the Earth’s equator, making one

rotation in 24 hours.

“Real-time” is a common term

which means that data is

collected and relayed to the

ground as soon as it occurs.

A radiometer is an

instrument that measures electromagnetic

radiation or energy.

The launch of the prototype Synchronous Meteorological Satellite, SMS-A, in May 1974

inaugurated the series of geosynchronous satellites that has provided systematic, continuous observations of weather patterns. A second prototype, SMS-B, followed in February 1975. The GOES program formally began with the

launch of the first operational spacecraft, GOES-A, in

1975, which was renamed GOES-1 when it reached orbit. GOES-2 and GOES-3 followed in 1977 and 1978,

respectively. These spacecraft obtained both day and

night data on the Earth’s weather from the Visible/Infrared Spin Scan Radiometer (VISSR), a scanning instrument that formed images of the Earth’s surface and cloud

cover for transmission to regional data-user stations for

use in weather prediction and forecasting and also for monitoring the space environment.

GOES 4-7 were similarly configured. GOES-4, launched in 1980,

introduced an improved VISSR, the VISSR Atmospheric Sounder

(VAS), which gathered the standard VISSR image data and also

sounded the atmosphere, enabling meteorologists to acquire temperature and moisture data profiles. From these profiles, scientists

could determine the altitudes and temperatures of clouds and draw

a three-dimensional picture of their distribution in the atmosphere, leading to more accurate

weather predictions. Using GOES imagery, meteorologists also measured the movement of

clouds at different altitudes and determined their wind direction and speed to better understand

atmospheric circulation patterns. A limitation of the VAS was that it could not gather imaging

and sounding data simultaneously but had to alternate between the two functions.

GOES-7, launched in 1987, was the last spinner-type geosynchronous spacecraft. It inaugurated

the use of geosynchronous satellites for international search and rescue efforts. The spacecraft

could receive signals from emergency transmitters on

ships and planes in distress and send them to ground stations that coordinated search and rescue efforts.

GOES 8-11 three-axis-stabilized satellites provided significant improvements. GOES-8, launched in 1994, carried separate and independently operating Imager and Sounder instruments. Now researchers

could gather both imaging and sounding data continuously without having to alternate between

the two operating modes. Image resolution also improved significantly, and the GOES search

and rescue system also became operational.

The GOES system has continued to improve with new technological innovations and sensors.

The present-day GOES spacecraft help meteorologists observe and predict local weather

events, including thunderstorms, tornadoes, fog, flash floods, and even snow squalls. GOES
3

Legend:

NSF - National Science Foundation VISSR - Visible/Infrared Spin Scan Radiometer Launch / Active Period

SMS - Synchronous Meteorological Satellite WEFAX - Weather Facsimile Standby / Inactive

VAS - VISSR Atmospheric Sounder Diminished capability / Other function assumed

74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01

YEAR

Deactivated Jan. 21, 1981

 Operational until Jan. 1976

 Deactivated Aug. 5, 1982

 Deactivated March 7, 1985

Operational until 1993 Deactivated May 2001

 Reactivated 1995 for NSF transmissions

Still limited operations

 Deactivated Nov. 22, 1988

 VAS failed Nov. 25, 1982

Deactivated July 18, 1990

 VAS failed July 29, 1984

VAS failed Jan. 21, 1989 Deactivated May 24, 1992

 Launch failure

 Stationkeeping fuel ran out - 1992

 Went to standby Jan. 1996

Parked June 1996

 Assumed PEACESAT communications duties Nov. 1999

Deactivated July 28, 1998

GOES-11

5/3/00

GOES-12

7/23/01

GOES-10

4/25/97

GOES-9

5/23/95

GOES-8

4/13/94

GOES-7

2/26/87

GOES-G

5/3/86

GOES-6

4/28/83

GOES-5

5/22/81

GOES-4

9/9/80

GOES-3

6/16/78

GOES-2

6/16/77

GOES-1

(SMS-C)

10/16/75

SMS-2

2/6/75

SMS-1

5/17/74

observations have proven helpful in monitoring dust storms, volcanic eruptions, and forest

fires. Currently, the system consists of GOES-8, operating as GOES-East in the eastern part of

the constellation at 75° west longitude, and GOES-10, operating as GOES-West at 135° west

longitude. GOES-11 is in standby mode and is serving as a spare that backs up both satellites.

GOES-12 was successfully launched from Cape Canaveral on July 23, 2001. See “Prior Spacecraft” beginning on page 29 for more detailed information about each spacecraft.

Mission History Summary
4 The Spacecraft

Overall, the program continues to provide environmental data for routine meteorological analyses

and forecasts, serve user agencies, and provide environmental data that helps expand knowledge of

storm development and forecast severe weather

events. It supports the Cospas-Sarsat system, contributes to the development of worldwide environmental warning services and enhancements of basic environmental services, improves the

capability for forecasting and providing real-time

warning of solar disturbances, and provides data

that may be used to extend knowledge and understanding of the atmosphere and its processes.

The GOES-NO/P/Q spacecraft, built by

Boeing Satellite Systems, Inc. (formerly

Hughes Space and Communications), are

based on the Boeing 601 spacecraft and are the

latest in the series of three-axis body stabilized

geosynchronous weather satellites. The new

Length (solar array to spacecraft body):

Height (Imager port to magnetometer

boom):

Depth:

Solar array:

Yoke panel:

At launch:

Dry mass:

Beginning of life:

End of life:

Battery:

Battery capacity:

Fuel:

Oxidizer:

Pressurant:

Delta III (also Atlas III-compatible)

On-Orbit

Configuration

Mass

Power

Propulsion

Launch Vehicle

Spacecraft Description Summary

331 in. (8.4 m)

358 in. (9.1 m)

113 in. (2.9 m)

28 ft. 8 in. (8.2 m)

7 ft. 9 in. x 6 ft. 0.1 in. (2.3 m x 1.8 m)

7,075.7 lb. (3,209.5 kg) (including fuel, oxidizer, and

pressurant)

3,402 lb. (1,543 kg)

2.22 kW at summer solstice, 2.47 kW at equinox

2.07 kW at summer solstice, 2.25 kW at equinox

Nickel hydrogen (NiH2

)

123 ampere-hours

Monomethylhydrazine

Nitrogen Tetroxide

Helium

Five years of operations plus two years of on-orbit storage. Five years of ground storage is

also possible.

Lifetime
5



GOES On-Orbit Configuration

satellites will accurately locate severe storms and other weather phenomena, resulting in precise

warnings to the public. The spacecraft enable the primary sensors to “stare” at the Earth and

thus frequently image clouds, monitor the Earth’s surface temperature, and sound the Earth’s

atmosphere for its vertical temperature and water vapor distribution. Atmospheric phenomena

can be tracked, ensuring real-time coverage of events such as severe local storms, tropical

hurricanes, and cyclones—meteorological events that directly affect public safety, property, and

ultimately, economic health and development. The figure below shows the GOES spacecraft in

its on-orbit configuration.

The spacecraft subsystems, such as telemetry and command, communications, mechanical, electrical, power, propulsion, attitude control, and image navigation and registration, have been designed to support the requirements of the on-board instruments and the data products and services that are described in this brochure.
6

1000

km

3000 km

4800 km

2700 km

U.S.

SCAN

West to East

8 km

SCAN

East to West

IMAGER SCANNING

GOES N

13.35 μm

(one 8 km)

3.9, 6.55,

and 10.7 μm

(two 4 km)

Visible

(eight 1 km)

GOES O-Q

3.9, 6.55, 10.7,

and 13.35 μm

(two 4 km)

Visible

(eight 1 km)

GOES Area Scan

The GOES-NO/P/Q spacecraft carry an Imager, a Sounder, and a collection of other space

environment monitoring instruments. Both the Imager and the Sounder have a flexible

scan control mechanism that allows the instruments to scan small areas as well as all of

North and South America and global scenes (called full-disk images). Small area scan selection

permits rapid and continuous viewing of local areas for monitoring of regional phenomena and

accurate wind determination. The scan control mechanism also allows continuous observations

of severe storms and changing, short-lived weather phenomena. Commands from the NOAA

control center select the position and size of the area for observation.

The resolution, or clarity, of each image depends on the size of the picture elements (pixels) in

the image that is being acquired. The size of each pixel, in turn, depends on which band is being

used. Different bands take images with different-size pixels (see “Imager Scanning” table

above). An image with pixels that are 4 km (2.5 miles) on each side provides twice the

resolution of an image whose pixels are 8 km (5 miles) on each side . All Sounder channels

generate data that have circular pixels with 10-km (6.2-mile) diameters.

Each range of Imager wavelengths generates images with

square pixels that are 1 km, 4 km, or 8 km on each side.

For instance, images produced at wavelengths of 10.20 -

11.20 micrometers (μm) have pixels that are 4 km (2.5

miles) on each side. A smaller number of pixels indicate

better-quality images. Note that the resolution for the 13.00

- 13.70 μm wavelength changes for GOES-O-Q.

The Instruments
7

Imager

 Imager

The Imager, developed by ITT A/CD (ITT Aerospace/Communications Division), Fort Wayne,

Indiana, is an imaging radiometer that uses data obtained from its five channels to continuously

produce images of the Earth’s

surface, oceans, severe storm

development, cloud cover,

cloud temperature and height,

surface temperature, and water vapor. It allows users to

identify fog at night, distinguish between water and ice

clouds during daytime hours,

detect hot spots (such as volcanoes and forest fires), locate a hurricane eye, and acquire measurements of

nighttime ground and sea surface temperatures.

The Imager simultaneously senses emitted thermal and reflected solar energy from selected areas of the Earth. It uses a scan mirror system to alternately sweep east to west and west to east

perpendicular to a north-to-south path. The rate of scanning allows the instrument to gather data

in its five spectral channels from a 1,864 x 1,864-mile area (3,000 x 3,000 km) in three minutes

and from an area of 621 x 621 miles (1,000 x 1,000 km) in just 41 seconds.

Imager Data Products

Products

Daytime cloud cover

Nighttime cloud cover

Water vapor

Earth and cloud images; sea surface

temperature and water vapor

Cloud cover and cloud height

Wavelength (μm)

visible - 0.52 - 0.71

3.73 - 4.07

5.80 - 7.30

10.20 - 11.20

13.00 - 13.70

Pixel size (km)

1

4

4

4

8 on GOES-N; 4 on

GOES O-Q
8

Sounder Channel Allocation and Purpose

Sounder

Detector

Channel

Number

Central

Wavelength

(μm) Purpose

Temperature sounding

Temperature sounding

Temperature sounding

Temperature sounding

Temperature sounding

Temperature sounding

Surface temperature

Surface temperature

Total ozone

Water vapor

Water vapor

Water vapor

Temperature sounding

Temperature sounding

Temperature sounding

Temperature sounding

Surface temperature

Surface temperature

Clouds

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

14.71

14.37

14.06

13.64

13.37

12.66

12.02

11.03

9.71

7.43

7.02

6.51

4.57

4.52

4.45

4.13

3.98

3.74

0.70

Longwave

Midwave

Shortwave

Visible

 Sounder

The Sounder, also built by ITT

A/CD, provides meteorologists with

a detailed description of conditions in

the atmosphere at any time. It gathers

data over an approximately circular

area extending from 60° north to 60°

south latitude, allowing meteorologists to deduce atmospheric temperature and moisture profiles, surface

and cloud-top temperatures, and

ozone distributions by mathematical

analysis and by adding to data from

the Imager. Sounder data is also used

in computer models that produce

mid- and long-range weather forecasts.

Detecting conditions that may lead to severe storms is one major function of the Sounder. Data

collected by the instrument is processed on the ground so that it generates a numerical designation called a “lifted index,”

which is an indicator of atmospheric stability and of how

much air near the surface would

keep rising were it lifted to the

middle of the atmosphere. The

less stable the atmosphere, the

greater the likelihood of severe

storms.

The Sounder probes the atmosphere measuring emitted radiation in one visible band and 18

thermal bands that are sensitive

to temperature, moisture, and

ozone as well as to reflected

solar radiation. It measures radiated energy at different depths

(altitudes) and also records surface and cloud-top temperatures

and ozone distribution. It looks
9



Sounder Filter Wheel Assembly

at conditions in “columns” of the atmosphere—cylindrical sections that extend from the Earth’s

surface to the upper reaches of the atmosphere.

The Sounder operates by means of

a scan mirror that steps across the

disk of the Earth in a west-to-east

and east-to-west direction along a

north-to-south path as the filter

wheel rotates.

The filter wheel has 18 filters, each

of which corresponds to a particular band or wavelength in the spectrum. Each filter allows only energy with a particular wavelength

to reach the detectors. All 18 filters

and the visible band are sampled

during each rotation, which occurs

10 times per second.

One-fourth of the wheel has no

filters, which allows time for the scanner to move, or “step,” to a new scan position during the

period of rotation. For the visible band, the reflected solar energy bypasses the filter wheel

completely and goes directly to the 19th channel visible detector. The Sounder’s detector array

assemblies sample four separate fields or atmospheric columns simultaneously.

The Sounder operates independently of and simultaneously with the Imager, using a similar

type of flexible scan mechanism system. The Sounder scans the full Earth and can be commanded to scan and provide soundings of local regions of interest. It can provide imagery over

the entire area that is visible to the Sounder, sector imagery, and scans of local regions. Sounder

data from the chosen scan area is fed into powerful computer programs that develop advanced

numerical weather prediction models for use by weather forecasters.

Space Environment Monitor

The Space Environment Monitor (SEM) consists of three instrument groups: 1) an energetic

particle sensor (EPS) package, 2) two magnetometer sensors, and 3) a solar x-ray sensor (XRS).

Operating at all times, the SEM provides real-time data to the Space Environment Center (SEC)

in Boulder, Colorado. The SEC, as the nation’s “space weather” center, receives, monitors, and

interprets a wide variety of solar terrestrial data and issues reports, alerts, warnings, and forecasts

for special events such as solar flares and geomagnetic storms (see http://www. sec.noaa.gov).
10

Elements of the EPS: the EPEAD, EPS DPU, HEPAD and MAGED/MAGPD

This information is important for military and civilian radio communication, satellite communication and navigation systems, electric power networks, geophysical exploration, Shuttle and

Space Station astronauts, high-altitude aviators, and scientific researchers.

Energetic Particle Sensor

The EPS, developed by Panametrics, Inc., measures the energetic particles at geosynchronous

orbit, including protons, electrons, and alpha particles. The radiation in the environment consists

of particles trapped within the Earth’s magnetosphere as well as particles arriving directly from

the sun and cosmic rays that have been accelerated deep in space.

The sensors accurately measure the number of particles over a broad energy range and are the

basis for operational alerts and warnings of hazardous conditions. Energetic particles pose a risk

to satellites and to astronauts, and they can disrupt navigation and communications systems used

on the ground and in aircraft.

The Magnetosphere Electron Detector (MAGED) and Energetic Proton, Electron, and Alpha

Detector (EPEAD), two elements of the EPS, detect electrons over the energy range of 30,000

electron volts (30 keV) to greater than 4 million electron volts (4 MeV), in eight channels. The

Magnetosphere Proton Detector (MAGPD), EPEAD, and High Energy Proton and Alpha Detector (HEPAD), which are additional EPS elements, detect protons over the energy range of 80

keV to greater than 700 MeV, in 16 channels. The EPEAD and HEPAD detect alpha particles

over the energy range 3.8 MeV to greater than 3,400 MeV, in eight channels.

The continuous long-term monitoring of the environment provided by these sensors forms the

basis for engineering guidelines for satellite design, for analyzing satellite failure and anomalous

behavior, for assessing the risk of human exposure to radiation, and for research leading to im-
11

proved models of the radiation

environment. The sensors on

the EPS have been expanded

on GOES-NO/P/Q to provide

coverage over an extended

energy range and with improved directional accuracy.

Magnetometers

The GOES-NO/P/Q satellites

have two identical magnetometers, provided by Science Applications International Corporation (SAIC), Inc. They can

operate independently and simultaneously to measure the

magnitude and direction of the

Earth’s geomagnetic field, detect variations in the magnetic

field near the spacecraft, provide alerts of solar wind shocks or sudden impulses that impact the

magnetosphere, and assess the level of geomagnetic activity. Magnetometer data is archived for

the scientific community and other interested users. One magnetometer is mounted on the end of

the boom 27.9 feet (8.5 m) from the spacecraft. The other is positioned on the same boom 2.6

feet (0.8 m) closer to the spacecraft. The second magnetometer sensor serves as a backup in case

the first magnetometer sensor fails and provides for better calibration of the magnetometer data

channel.

GOES Sun-Observing Package

The magnetosphere is the

comet-shaped region

around the Earth that is

affected by the Earth ́s

magnetic field. It extends

some 37,282 miles (60,000

km) from the Earth on the

side facing the sun, but on

the opposite side, it

extends much farther. The

boundary of the magnetosphere is called the

“magnetopause.” Read

about the magnetosphere

at http://www-istp.gsfc.

nasa.gov/Education/.
12

X-Ray Sensor and Extreme Ultraviolet Sensor

The XRS is an x-ray telescope that observes and measures solar x-ray emissions in two

ranges—one from 0.05 to 0.3 nanometers (nm) and the second from 0.1 to 0.8 nm. In real-time,

it measures the intensity and duration of solar flares in order to provide alerts and warnings of

potential geophysical responses, such as changes in ionospheric conditions, that can disrupt radio communications and Global Positioning System (GPS) signals. XRS data is also used to estimate solar flare parameters such as rise-time (how quickly a flare grows) and the length and

temperature of a flare for use in energetic proton predictions.

The five-channel EUV telescope is new on the GOES-NO/P/Q satellites. It measures solar extreme ultraviolet energy in five wavelength bands from 10 nm to 126 nm. The EUV sensor provides a direct measure of the solar energy that heats the upper atmosphere and creates the ionosphere. Changes in solar EUV output can change the density of the upper atmosphere by a factor

of 10, which will cause increased drag for satellites in low-Earth-orbit. Similarly, these changes

in EUV level can increase the density of the ionosphere by a factor of 10, which will affect radio

communications and satellite navigation.

Both the XRS and EUV are provided by Panametrics, Inc., and are part of the sun-observing

package mounted on the solar panel yoke assembly. The entire package (including the SXI) continually points at the sun by using a Precision Sun Sensor (PSS) to control the solar panels to

track the sun in azimuth and the x-ray positioner (XRP) to track the sun in elevation.

Solar X-Ray Imager

The SXI, developed by Lockheed Martin Advanced Technology Center (LMATC), uses a telescope assembly to observe the sun’s x-ray emissions and provide early detection and location of

flares. These observations allow space weather forecasters to monitor solar features and activities

such as solar flares, loops, coronal holes, and coronal mass ejections—clouds of charged particles shooting toward Earth—from the sun. Knowledge of the location and size of these phenomena greatly improves the forecaster’s ability to predict which solar phenomena may affect the

Earth and its atmosphere and to determine when forecasts and alerts of space weather conditions that may interfere with ground and space systems should be issued.

Space Environment Monitoring Terminology

Cosmic rays - A rain of fast ions that constantly bombards the Earth, coming from distant space and much

more energetic than any found in the magnetosphere.

Ionosphere - A region of the upper atmosphere that extends from about 30 miles (50 km) to 250 miles (400

km) above the Earth’s surface. It is characterized by the presence of ions and electrons that affect radio

communications and satellite navigation.

Magnetometer - An instrument that measures the magnitude and direction of the Earth’s magnetic field.
13

SXI Telescope Assembly

Space weather can have quite far-reaching effects. NOAA categorizes these as

radio blackouts, radiation storms, and

geomagnetic storms. Radio blackouts interfere with military and commercial

communications and navigation systems.

Radiation storms can damage operating

spacecraft and expose humans to excessive radiation during high-altitude missions. Geomagnetic storms damage power utility systems and disrupt

communications and navigation systems.

NOAA and U.S. Air Force forecasters will

use data and images from the SXI to monitor solar conditions that affect space weather conditions, including the dynamic environment of

energetic particles, solar wind streams, and coronal mass ejections emanating from the sun.

The SXI captures full-disk images of the sun in the x-ray spectral band from 0.6 to 6.0 nm. It

is commanded from the ground and can capture at least one image per minute. Ground command can reconfigure the SXI to take image sequences with varying exposure times in different

parts of the x-ray spectral band, depending on the level of solar activity. If enabled by ground

command, the instrument can also automatically change its imaging sequences during very

high solar activity.

The telescope consists of entrance filters that block radiation outside the 0.6-to-6.0-nm range

and also protect the Charge Coupled Device (CCD) from undesired radiation. The SXI’s x-ray

mirror focuses the image on the camera,

while the High Accuracy Sun Sensor

(HASS) keeps the instrument focused on

the sun in the east-west direction.

Images are captured in digital form on the

CCD. From there, they are transmitted

directly to NOAA’s SEC, which processes

the data in real time for its own use and

use by others in predicting space weather.

In processing the data, the SEC corrects

known image defects and calibrates and

stores each image. The calibrated images

are used to automatically locate solar

Solar X-Ray Imager flares, produce movie sequences, calculate
14

coronal hole indices, display on real-time monitors, and produce products for the general public.

The user will be able to view PNG and MPEG files* and order high-fidelity images for research.

Data will be archived at the NOAA National Geophysical Data Center (NGDC) at http://www.

ngdc.noaa.gov.

Instrument of Opportunity

The GOES-NO/P/Q spacecraft are designed so they can accommodate an additional observational instrument. This instrument of opportunity would be provided by universities, research

institutions, or other organizations that have expressed an interest, can finance the costs associated with the opportunity, and can meet the instrument accommodation requirements.

At present, no instruments of opportunity have been identified for inclusion on any of the GOES

spacecraft in the NO/P/Q series.

*PNG and MPEG are file formats for viewing graphics and motion pictures.

The SXI provides real-time transmissions of x-ray images of the sun through its unprecedented monitoring of solar changes. In this image, the brightest spots indicate solar flares—

explosive releases of plasma from the sun’s surface into its atmosphere. Coronal holes

appear as dark regions. They are associated with weak magnetic field lines and indicate

sources of geomagnetic storms. This image was produced on September 7, 2001, by the first

SXI, flown on GOES-12. It was built by NASA’s Marshall Space Flight Center.
15Search and Rescue

Cospas-Sarsat System

GOES spacecraft carry a search and rescue transponder that detects signals transmitted by 406-

MHz emergency beacons carried by aircraft (Emergency Locator Transmitters—ELTs), maritime

vessels (Emergency Position Indicating Radio Beacons—EPIRBs) and individuals (Personal Locator Beacons—PLBs). Optional GPS-equipped beacons will allow GOES spacecraft to precisely

locate distress signals and significantly improve the response time for providing rescue assistance.

When the transponder on a GOES satellite detects an alert, it transmits the alert from the

spacecraft to a Local User Terminal (LUT) in Canada called a GEOSAR Ground Station. (Another geosynchronous LUT will soon be installed at Suitland, Maryland.) When the LUT receives the search and rescue data, it determines the distress location and forwards the data to

the U.S. Mission Control Center (USMCC) at Suitland, Maryland. The signals sent by the

GOES spacecraft can be used in conjunction with the signals sent by the polar-orbiting satellites in low-Earth-orbit to determine the location of the distress call. Satellites in low-Earth-orbit transmit alerts they receive to a LUT located within the field of view of the satellite. U.S.

LUTs for satellites in low-Earth-orbit are located at Fairbanks, Alaska; Vandenberg Air Force

Base, California; Wahiawa, Hawaii; Johnson Space Center, Houston, Texas; NOAA, Suitland,

Maryland; Anderson Air Force Base, Guam; and Sabana Seca, Puerto Rico.

When the location of the distress call is determined, the MCC identifies the appropriate Rescue

Coordination Center (RCC) and forwards the distress data after removing redundant information. Additional LUTs and MCCs are located in Canada, France, Russia, and 10 other cooperating countries. All MCCs cooperate in forwarding data to provide rapid global delivery of distress locations received through the satellites.

The U.S. portion of the Cospas-Sarsat system is operated by the NOAA SARSAT Office in

Suitland, Maryland. Additional information about the system, including the latest U.S. and

worldwide lives saved, can be obtained at http://www.sarsat.noaa.gov. As of June 2001, more

than 12,800 lives have been saved around the world.
16

Cospas-Sarsat System

1. Emergency beacons are activated in situations of “grave and imminent danger” when lives are at risk.

2. Emergency alerts received by the satellites are retransmitted to one or more of 38 automatic (unstaffed) ground

stations worldwide. These stations are called Local User Terminals (LUTs).

3. Messages are routed to a Mission Control Center (MCC) in the country that operates the LUT. Routed messages include beacon location computed at the LUT if the message was received by one of the system’s lowEarth-orbiting satellites. Messages received by system satellites in geosynchronous orbit provide instantaneous

alerting and can include location information if the beacon is a self-locating type.

4. After validation processing, alerts are relayed depending on beacon location or country of registration (406-MHz

beacons only) to either another MCC or to the appropriate Rescue Coordination Center (RCC).

5. The U.S. Coast Guard and Air Force operate U.S. RCCs. The Air Force Rescue Coordination Center at Langley

AFB, Virginia, coordinates all inland search and rescue activities in the lower 48 states. Usually, the actual

search and rescue is carried out by the Civil Air Patrol or local rescue services. The Coast Guard coordinates

and conducts most maritime search and rescue missions from RCCs located in nine Command Districts around

the United States and two Rescue Sub-Centers (RSCs) in San Juan, Puerto Rico, and Guam. The Coast Guard

also coordinates rescue missions in Hawaii.

In Alaska, the Air Force operates an Alaskan Rescue Coordination Center in Anchorage at Ft. Richardson. Air

National Guard units, the Alaska State Police, and local authorities carry out Alaskan search and rescue.
17Launch and Orbit

Composite 13.1-ft/4-m

payload fairing

Single cryogenic

engine

13.1-ft/4-m isogrid firststage fuel tank

Stretched graphiteepoxy strap-on motors

(thrust vector control

on 3 of 9 motors)

Isogrid first-stage

liquid oxygen tank

Avionics

Rocketdyne RS27A main engine

Event Time From Ignition (sec.)

Ignition 0

Maximum dynamic pressure 42

Jettison ground lit solid motors 83

Jettison air lit solid motors 162

Jettison fairing 226

Main engine cutoff 260

Second stage ignition 281

Second stage cutoff 1 762

Second stage restart 1307

Second stage cutoff 2 1510

Spacecraft separation 2174

Delta III Major Events

ADelta III space launch vehicle (SLV) will be

used to launch GOES-N and GOES-O. This

SLV has evolved from the Delta II, which has

been successfully used for more than 10 years. The Delta

III, provided by Boeing, is a two-stage vehicle with a payload fairing, payload attach assembly, and avionics system. It can deliver a payload of 8,400 lbs. (3,810 kg) to

geosynchronous transfer orbit.

The Delta III first stage is powered by an RS-27A main

engine with two vernier engines used to control roll during main engine burn and also attitude between main engine cutoff (MECO) and first-stage separation. To enhance first-stage performance, the SLV uses nine 46-in.

(1.17-m)-diameter Alliant Techsystems graphite-epoxy

motors (GEMs), derived from those used on Delta II but

which are larger and produce more thrust.

A Pratt & Whitney RL10B02 engine, which produces

24,750 lbs. (111,094 newtons) of thrust, powers the second stage. This engine, derived from the RL10 engine,

has flown for more than 30 years. The second stage carries more propellant than the Delta II and burns cryogenic

(cold) fuels, which produce more energy, allowing lift of

heavier payloads.

The Delta III uses a 13.1-ft. (4-m)-

diameter fairing that separates into

halves in flight to permit satellite

deployment. The payload is placed

into the fairing before it is transported

to the launch pad and integrated with

the launch vehicle.

GOES-P and GOES-Q could be

launched from Delta IV or Atlas III

launch vehicles. The Atlas III is an

improved version of the established

Atlas II family of launch vehicles. The

Atlas consists of a booster section, a

Delta III Space Launch Vehicle
18

Orbit Terminology

Apogee - The part of an orbit where the spacecraft or launch vehicle is the farthest from the Earth.

Geostationary orbit - An orbit in which the satellite is always in the same position in relation to the Earth. It is

approximately 22,240 miles (35,790 km) above the Earth’s equator.

Liquid apogee motor - A motor that fires at apogee and at perigee to circularize the orbit. This motor uses liquid

fuel.

Orbit raising - The sequence of events that maneuvers the spacecraft into its final orbit.

Perigee - The part of an orbit where the spacecraft or launch vehicle is closest to the Earth.

Supersynchronous transfer orbit - A temporary orbit whose apogee is farther away from the Earth than the

final orbit.

Trajectory phase - The events that take place when the spacecraft is moving into its correct orbit.

Transfer orbit - A temporary orbit that the spacecraft moves in before moving to its final position.

Transfer orbit phase - The part of the orbit lasting from the time when the spacecraft separates from the

launch vehicle to the last perigee motor firing (the motor firing that occurs when the spacecraft is at its perigee,

i.e., closest to the Earth).

Atlas III Launch Vehicle

sustainer section, and an upper stage. It would be provided by

Lockheed Martin Space Systems Company.

The GOES-NO/P/Q satellites will be launched from Cape

Canaveral Air Force Station, Florida. They will be launched

into a geosynchronous orbit approximately 22,240 statute

miles (35,790 km) above the equator with an inclination angle

of plus or minus 0.5° to the equator.

The GOES launch and orbit insertion sequence starts before

liftoff with a buildup of thrust following Stage I engine ignition. Then hold-down bolts are fired and the launch vehicle

lifts off. After clearing the launch pad, the launch vehicle

climbs to its desired flight altitude and begins to pitch over in

the trajectory phase. The solid strap-on engines are jettisoned

at approximately 162 seconds after liftoff. The payload fairing is jettisoned from the launch vehicle at approximately 226

seconds. The control logic then provides a signal that cuts off

the main engine and, 21 seconds later, ignites the second

stage. The second stage is shut down at 762 seconds and restarted at 1,307 seconds. Final second-stage cutoff (SECO) occurs at 1,510 seconds.
19

Typical Delta III Geosynchronous Transfer Orbit Sequence (Times Are Approximate)

GOES Launch and Orbit-Raising Mission Phases

The spacecraft separates from its upper stage 36 minutes (2,174 seconds) after liftoff. The SLV

then injects the spacecraft into a highly elliptical supersynchronous transfer orbit to begin the

transfer orbit phase. A liquid apogee motor proceeds to place the spacecraft into the proper

geostationary orbit through a sequence of several motor burns. The spacecraft arrives at its final

location about 17 days after launch. During the test period that follows, thrusters are used to

adjust the orbit.
20

GOES Coverage Area

Coverage Area

During the launch sequence and transfer orbits, near-continuous coverage is provided by telemetry and control stations at Wallops, Virginia; Goldstone, California; Madrid, Spain; and

Canberra, Australia.

Normally, two GOES spacecraft operate concurrently. GOES-East is stationed at 75°

west longitude, and GOES-West is located at 135° west longitude, both over the equator. GOES-East observes North and South America and the Atlantic Ocean. GOES-West

observes North America and the Pacific Ocean to the west of Hawaii—the area often called “the

birthplace of North American weather systems” by weather forecasters. Together, these satellites

provide coverage for the central and eastern Pacific Ocean; North, Central, and South America;

and the central and western Atlantic Ocean. The images that are produced from this hemispheric

coverage and which are familiar to many television viewers are called “full-disk images,” such

as the image on the cover of this brochure.

At least one GOES spacecraft is always within view of Earth-based terminals and ground stations within the western hemisphere. The command and data acquisition station (CDAS) can

see both spacecraft so that it can transmit commands and receive data from each satellite simultaneously. Data collection platforms (DCPs) within the coverage area of each spacecraft can

transmit their sensed surface-based data to the CDAS by means of the onboard data collection

system (DCS). Ground terminals can also receive processed environmental data and EMWIN

and LRIT/WEFAX transmissions.
21Image Navigation and Registration

Raw Imager and Sounder data received at the NOAA CDAS is processed in the spacecraft support ground system with other data to provide accurate, Earth-located, calibrated imagery and

sounding data in near real time for uplink to the satellite and retransmission from the GOES

spacecraft to primary end users, principally the seven National Weather Service field service stations located throughout the United States.

The GOES Image Navigation and Registration (INR) system ensures that Imager and

Sounder data is consistent during the day by maintaining the pointing accuracy of the

instruments. Image navigation is the process of determining the coordinates (Earth latitude and longitude) of each pixel within an image or sounding. Image registration is the process

of maintaining the coordinates of each pixel within an image or sounding at the same Earth latitude and longitude independent of time.

While in orbit, the spacecraft and consequently the instruments move slightly, which can

cause the instruments to look at and scan slightly different areas of the Earth. Other conditions, such as vibrations, heat-related distortions, and erroneous signals to the instrument mirrors, can also lead to pointing inaccuracies that can produce inconsistent data. The INR system

continuously adjusts the aim of the instruments’ scan mirrors to compensate for the motion of

the spacecraft and other disturbances. The system uses image landmarks, star views, and satellite range data collected throughout the day to make the adjustments.

INR Performance Requirements

Microradians Kilometers (km)

IMAGER (μrad)

0 Imager navigation accuracy 56 2

0 Registration within an image 42 1.5

0 Registration between repeated images

15 minutes 28 1

90 minutes 42 1.5

24 hours 112 4

0 Channel-to-channel registration 28 1

SOUNDER

0 Earth location accuracy 280 10

0 Registration within 120-minute sounding 84 3

0 Registration between repeated soundings

90 minutes 84 3

24 hours 224 8
22

This image shows the

Jarrell, Texas, tornado

event on May 27, 1997.

The red areas are clouds

with severe storm activity.

The image does not

distinguish between

tornado activity and other

severe storms. Radar and

other ground data are

needed to provide that

additional information.

Data Products and Services

GOES instruments generate many data products and provide several services to the

science community, meteorologists, and the public. These include the commonly seen

images produced by the Imager and Sounder; data from the SEM that is transmitted to

and processed by the SEC in Boulder, Colorado; information gathered by data collection platforms; text, images, and graphics transmitted by EMWIN; data transmitted through the LRIT/

WEFAX system; and search and rescue services. A sample of images generated by the Imager

and Sounder and from SEM data appears below and on the pages that follow. For additional data

products and images, see the GOES Products and Services Catalog published by the National

Environmental Satellite, Data, and Information Service (NESDIS) at http://orbit-net.nesdis.gov/

arad/fpdt/goescat and at http://osdacces.nesdis.noaa.gov:8081/satprod/.

Absorption of highfrequency radio waves in

the D-Region of the ionosphere (the lowest layer of

the ionosphere) is directly

affected by the level of solar x-ray flux. The D-Region absorption product

was developed to assist

high-frequency radio operators and is based entirely

on real-time data from the

x-ray sensor.
23

This Sounder-derived image shows the

tornado event that occurred near Jarrell,

Texas, on May 27, 1997. The numbers,

called a lifted index, represent atmospheric

stability. The more negative numbers

indicate a more unstable atmosphere. A -10

or lower is considered very unstable—a

breeding ground for tornadoes and other

severe storms. On this map, the most

unstable area is bordered in red, where

lifted index numbers fall as low as -16 and

where the tornado later broke out.

This image, also derived from Sounder

data, shows the degree of stability in the

atmosphere as expressed in a lifted index

scale that is color-coded at the bottom of

the image. The red areas of the map in

eastern Texas correspond to quite negative

lifted index values. They are the most

unstable, with serious potential for

tornadoes or other severe storm activity.

The beige areas of the map show positive

lifted index values. They indicate stable

conditions over the southwestern states.

Wind data is derived from the GOES

Sounder’s water vapor channels in the

mid-troposphere, the level of the atmosphere where the jet stream develops and

carries weather systems. The straight end

of a wind barb points in the direction that

the wind is blowing. The density of a

barb’s tail shows the intensity of the wind.

The color of a barb shows its altitude.
24

This image of Hurricane Floyd was taken on

September 15, 1999, from a color

combination of GOES visible channel 1 and

infrared channels 2 and 4. This color

combination presents high clouds as white,

low clouds as yellow (such as in the eye of

the hurricane), and the ocean as dark blue.

Several fires in northeastern Florida are

seen in this image, a color combination

of GOES visible channel 1 and infrared

channels 2 and 4. Smoke from the fires

appears as low (yellow) haze that

stretches eastward from northern Florida

out over the Atlantic Ocean.

This image shows low-level visible clouddrift winds around hurricanes Eugene and

Dora. Three 15-minute sectors (above the

horizontal black line) and three 30-minute

sectors (below the black line) were used to

derive the visible winds from Imager data.

Note the significant improvement in detail

of the wind field from data that was

obtained in 15-minute intervals in the top

half of the image. The straight end of each

wind barb points in the direction that the

wind is blowing.
25

The GOES communications subsystem consists of the antennas and transponders that allow GOES to receive and transmit data. This includes raw instrument data transmitted to

the ground, processed instrument data that is received on the spacecraft and then retransmitted to ground users, search and rescue data, weather data sent by the LRIT/WEFAX service,

reports from the data collection platforms (DCPs), and the wide range of data transmitted by the

Emergency Managers Weather Information Network (EMWIN).

The communication antennas on the spacecraft are mounted on the panel that faces the Earth.

They send and receive data from the ground stations located within the GOES coverage area.

Particular types of antennas, called L-band, S-band, and UHF (ultra-high frequency) antennas,

provide communications for specific purposes. Some transmit data from the spacecraft to the

ground (called downlink) while others transmit data from the ground to the spacecraft (uplink).

For instance, an L-band antenna downlinks search and rescue data from the spacecraft to the

ground while the UHF antenna receives search and rescue data and data from the DCPs. Additional antennas also receive data that is used to control the spacecraft and instruments.

RF

Link

(processed data)

Internet Link

Processed data

is broadcast

to users

NOAA

World

Weather

Building

Camp Springs, MD

Satellite

Operations

Control

Center

Suitland, MD

T-1 Link

Commercial

terminals

Raw instrument

data is transmitted

to Earth

Backup

Command and

Data Acquisition

Station, GSFC

Greenbelt, MD

Processed

instrument data

is transmitted

back to GOES

Data is

processed

at the NOAA

Command and

Data Acquisition

Station

Wallops, VA

Raw SXI and SEM data

is transmitted to the

Space Environment

Center, Boulder, CO

in separate streams

Legend

Raw instrument data

Processed instrument

data back to GOES

Processed data to users

T-1 Link

Internet Link

RF Link

GOES Communications System (Simplified)

Communications
26

 Sensor Data

After the raw Imager and Sounder data is processed on the ground, the processed data is uplinked

to the spacecraft. This processed data is then downlinked to the Satellite Operations Control Center (SOCC) at Suitland, Maryland, and transmitted to the World Weather Building at Camp

Springs, Maryland, for subsequent distribution to data users, who typically are staff of satellite

field service stations located throughout the United States. The SOCC also receives diagnostic

data that describes the performance of the Imager and Sounder on the multi-data downlink.

Data Collection System

The Data Collection System (DCS) is a communications relay system that handles information

gathered from more than 19,000 data collection platforms located in remote areas. The platforms consist of buoys, free-floating balloons, and weather stations. Sensors on the platforms

measure environmental factors such as atmospheric temperature and pressure and the velocity

and direction of the ocean and wind currents. The DCS transponder on board the spacecraft collects these measurements and provides near real-time relay of environmental data for centralized archiving and distribution. The digital data is used to develop analyses of environmental

events such as tsunamis, tropical cyclones, and floods and to map river stages, soil conditions,

and snow depth.

Data Collection System
27

LRIT/WEFAX

The digital Low Rate Information Transmission (LRIT) data originates from the National Weather

Service and from NOAA image-processing facilities. The LRIT digital WEFAX products will be

similar to the current analog service and is planned to improve the quality of the current WEFAX

products. The LRIT is an international standard for data transmission that is supported by all operational geostationary meteorological satellites flown by the United States, European agencies,

Japan, China, and Russia. This system can contain significantly more meteorological data, imagery, charts, and other environmental information than the current WEFAX system.

Emergency Managers Weather Information Network

The EMWIN data service became operational in June 1996. It transmits more than 50,000 pages

of text, images, and graphics each day to more than 10,000 users in 35 countries. The service

transmits simple, reliable, and affordable data continuously to its data user community.

 Command and Data Acquisition

The primary command and data acquisition station (CDAS)

is located at Wallops, Virginia. A NOAA backup CDAS is

located at NASA’s Goddard Space Flight Center (GSFC) in

Greenbelt, Maryland. This backup station, which became

operational in September 2000, normally operates in a

standby mode. If the primary station at Wallops is threatened or hit by a hurricane, the backup station becomes operational and takes over command and data acquisition

functions—ensuring that data from GOES-East or GOESWest will continue to flow. There are three new 54-ft. (16.4-

m)- antennas, two at Wallops and one at GSFC, which are

designed to operate through a Category 3 hurricane (130

miles per hour) (209 km/hr) and can survive a Category 5

hurricane (155+ miles per hour) (249+ km/hr).

The CDAS carries out command and data acquisition and

processed data relay functions for the GOES program. It

transmits commands to the operational satellites and acquires and records instrument and engineering data received from the satellites. Raw instrument

data is processed at the CDAS. The processed data is then transmitted to the satellites for rebroadcast to users.

16.4-Meter Backup Antenna at

Goddard Space Flight Center
28NASA’s and NOAA’s Roles and Support Systems

NOAA and NASA are actively engaged in a cooperative program to continue the GOES

system with the launch of the GOES NO/P/Q satellites. Since 1974, the two partners

have worked together to develop, perfect, and operate the GOES program. The current

GOES spacecraft are a key element in NOAA’s National Weather Service modernization program.

NASA’s GSFC procures, develops, and tests the spacecraft, instruments, and unique ground

equipment. Following deployment of the spacecraft from the launch vehicle, GSFC is responsible for the mission operations phase leading to the injection of the satellite into geostationary

orbit and initial on-orbit satellite checkout and evaluation.

NOAA is responsible for program funding and the on-orbit operation of the system. NOAA

also determines the need for satellite replacement. NESDIS is the arm of NOAA that operates the GOES system. It is responsible for implementing, operating, and maintaining the

SOCC facility at Suitland, Maryland; the CDAS at Wallops, Virginia; and the command

and data acquisition backup station at GSFC in Greenbelt, Maryland.

NOAA is also responsible for processing, analyzing, disseminating, and archiving all operational data, which is available to government researchers and others for research and environmental applications. NOAA’s Central Data and Distribution Facility (CDDF) at the World

Weather Building in Camp Springs, Maryland, and the Space Environment Center, along with

the National Geophysical Data Center (NGDC), in Boulder, Colorado, disseminate the data.

NOAA and NASA jointly design, develop, install, and integrate the ground system needed to

acquire, process, and disseminate the data from the satellite sensors.

NASA Support Facilities

The NASA Integrated Services Network (NISN) (formerly NASCOM) provides voice and communications data circuits during prelaunch, launch, and postlaunch activity. NASA’s Kennedy

Space Center is responsible for providing support for contractor-provided launch services.

NOAA Support Facilities

The Satellite Operations Control Center (SOCC) is located at Suitland, Maryland. The SOCC

is used as the focal point during the GOES launch operations activity. The SOCC is responsible

for obtaining necessary satellite data in real time, processing this data for display and analysis,

and performing satellite command operations and mission scheduling. The SOCC also supports

the operational phase of the mission after satellite handover to NOAA.

The Space Environment Center at Boulder, Colorado, receives, processes, and validates data

from the SEM and SXI that is used for real-time space weather operations and prepared for archives that are located at the NGDC.
29Prior Spacecraft

Launch Support

The Deep Space Network (DSN), which is maintained and operated by the Jet Propulsion

Laboratory (JPL), supports the launch of GOES spacecraft. DSN tracking stations are located at

Madrid, Spain; Canberra, Australia; and Goldstone, California. Additional launch support is provided by NOAA and NASA facilities at Wallops, Virginia, and Merritt Island, Florida.

GOES History

SMS-1 (SMS-A) was launched on May 17, 1974, from the Eastern Test Range (ETR) at Cape

Canaveral, Florida. It was the first geostationary meteorological satellite. Launched from a Delta

2914 space launch vehicle, its objectives were to

evaluate a prototype operational meteorological satellite

for NOAA’s National Weather Service and provide

regular daytime and nighttime meteorological

observations in support of the national operational

meteorological satellite system. The principal instrument

on board was the Visible/Infrared Spin Scan Radiometer

(VISSR), which provided day and night imagery of

cloud conditions. The satellite was also equipped with a

SEM and a DCS. The satellite also had the capability to

perform facsimile transmissions of processed images and

weather maps to WEFAX field stations. The satellite was

positioned in a geostationary orbit directly over the

equator at 45° W (over the central Atlantic), which provided continuous coverage of the central

and eastern United States and the Atlantic Ocean. It was operational until January 1976 and was

deactivated and boosted out of orbit on January 21, 1981.

SMS-2 (SMS-B) was launched February 6, 1975,

from a Delta 2914 space launch vehicle. It was

equipped with a VISRR, SEM, and DCS and had

WEFAX capability. It was placed in a geostationary

orbit directly over the equator at 135° W (over the

east-central Pacific Ocean). The satellite was deactivated August 5, 1982. SMS-1 and SMS-2 proved the

viability of geosynchronous meteorological satellites.

GOES-1 (GOES-A) was the first in the series of

Geostationary Operational Environmental Satellites.

It was launched from a Delta 2914 launch vehicle on

October 16, 1975. Its instrument complement was

Composite Photo Showing the OnStation Position of SMS-1 in 1974

SMS-B Erected Atop Its Delta Booster,

1975
30

identical to SMS-1 and SMS-2. GOES-1 was placed over

the Indian Ocean west of SMS-2 so that the combined coverage of the three satellites would include nearly 60 percent

of the Earth’s surface. It operated successfully in this orbit until June 1978 when it was relocated to replace

SMS-2 and GOES-3 replaced GOES-1. It was deactivated on March 7, 1985.

GOES-2 (GOES-B) was launched on June 16, 1977, from a

Delta 2914 launch vehicle. Its instrument complement was

identical to the SMS and GOES-1 satellites. GOES-2 was

placed in orbit directly over the equator at 60° W to replace

SMS-1. It was operational until 1993. The satellite was reactivated in 1995 to broadcast National Science Foundation

(NSF) transmissions from the South Pole to public broadcasting facilities in the United States.

The WEFAX system on GOES-2 continued to operate, although cloud images were no longer

being received from the system. The satellite was deorbited at the beginning of May 2001.

GOES-3 (GOES-C) was launched June 16, 1978, from a Delta 2914 launch vehicle. The satellite was used to replace GOES-1 and to support the Global Atmospheric Research Program

(GARP) over the Indian Ocean. It had the same instruments and capabilities as the earlier

GOES spacecraft. GOES-3 is currently being used by the University of Miami for communications purposes.

GOES-4 (GOES-D) was launched September 9, 1980, from a Delta 3914 launch vehicle. It

was the first geostationary satellite to provide continuous

vertical profiles of atmospheric temperature and moisture,

which its primary instrument, the VISSR Atmospheric

Sounder (VAS), provided. The VAS also provided both

day and nighttime imagery of cloud conditions. Instrument limitations did not permit both types of operations

simultaneously. The satellite also used new despun

S-band and UHF antennas to relay meteorological data

from more than 10,000 surface locations into a central

processing center for incorporation into numerical

weather prediction models and to transmit processed images and weather maps to WEFAX

field stations. It was also equipped with a SEM and DCS similar to those on previous GOES.

GOES-4 was placed in orbit at 135° W to replace the failing GOES-3. GOES-4’s most serious

anomaly occurred on November 25, 1982, when the VAS’s scan mirror stopped during retrace

after exhibiting excessively high torque. Efforts to restore either the visible or infrared capability were unsuccessful. It was deactivated November 22, 1988.

GOES-1 Image, October 25, 1975

When satellites are launched,

they have a letter designation.

After they reach orbit, they are

assigned a number. This

prevents a missing number if a

spacecraft does not reach orbit

successfully.
31

GOES-5 (GOES-E) was launched May 22, 1981, from a Delta 3914 launch vehicle. Its instrument complement was identical to GOES-4. It was placed in orbit at 75° W longitude. The satellite failed on July 29, 1984, when a VAS encoder lamp filament burned out that was needed to

read the angle of the scan mirror used to obtain images. It was deactivated on July 18, 1990.

GOES-6 (GOES-F) was launched April 28, 1983, from a Delta 3914 launch vehicle. It was designed to replace GOES-4 and was originally placed in orbit at 136° W. After GOES-5 failed, it

was moved to a central location at 98° W. When GOES-7 was placed in service, it was returned

to its original location. The VAS imager on GOES-6 failed on January 21, 1989, so direct readout images and soundings were no longer available. WEFAX data continued to be transmitted to

the data user community until the spacecraft was deactivated on May 24, 1992.

GOES-G was launched May 3, 1986, from

a Delta 3914 launch vehicle. The spacecraft

did not reach operational orbit because of a

failure in the launch vehicle.

GOES-7 (GOES-H) was launched February

26, 1987, from a Delta 3924 launch vehicle

and placed in orbit at 75° W. The spacecraft

was moved to 98° W in July 1989 following

the January 1989 failure of GOES-6. In

1992, GOES-7 ran out of stationkeeping

fuel, as expected. GOES-7 went to standby

in January 1996 and was parked at 95° W in

June 1996. Consequently, the VAS instrument and the associated data, along with

WEFAX, DCS, and search and rescue services through GOES-7, were deactivated. In midNovember 1999, GOES-7 was moved to 175° W to take over the communications-relay duties

of PEACESAT. The high orbital inclination made it possible to relay data from near the poles,

particularly to support the National Science Foundation science group at the South Pole. In addition to the same instrument complement as the earlier GOES, GOES-7 carried experimental

search and rescue equipment that allowed near-instantaneous detection of emergency distress

signals on the ground transmitting at 406 MHz.

GOES-8 (GOES-I) was launched April 13, 1994, from an Atlas-I/Centaur launch vehicle. In

2001, it is operational as GOES-East at 75° W. It was the first in a new series of three-axis stabilized GOES that provided significant improvements over the previous GOES spin-stabilized

spacecraft in weather imagery and atmospheric sounding information. The satellite is equipped

with a separate Imager and Sounder, which allows simultaneous and independent imaging and

sounding. Previously, both functions were performed alternately by a single instrument. GOES8 features a flexible scan mechanism that offers small-scale area imaging, resulting in improved

VAS Was Found on GOES-4 Through GOES-7
32

short-term forecasts over local areas. It

is also equipped with a SEM and DCS,

has WEFAX capabilities, and performs

near-instantaneous relay functions for

the Sarsat system with its dedicated

search and rescue transponder.

GOES-9 (GOES-J) was launched May

23, 1995, from an Atlas-I/Centaur

launch vehicle into a geostationary orbit at 135° W. It was deactivated on

July 28, 1998, because of failing bearings in the momentum wheels and is in

storage.

GOES-10 (GOES-K) was launched April 25, 1997, from an Atlas I/Centaur launch vehicle and

was placed in orbit at 105° W. It has the same instrument complement as GOES-8 and GOES-9.

In the spring of 1998, GOES-10 was shut down and designated an “on-orbit spare” until the

failure of GOES-8 or GOES-9. A month after launch, the GOES-10 solar array ceased rotating,

but, due to the ingenuity of the GOES government-industry team, it was possible to invert the

satellite, modify software, and operate the solar array in the reverse direction. Shortly thereafter,

GOES-9 began experiencing problems with its momentum wheels, and GOES-10 was placed in

active service as GOES-West, positioned at 135° W.

GOES-11 (GOES-L) was launched May 3, 2000, from an Atlas Centaur IIA launch vehicle and

placed in storage mode at 105° W in August 2000. It has the same instrument complement as

GOES-8, 9, and 10.

GOES-12 (GOES-M) was launched July 23, 2001, from an Atlas Centaur IIA launch vehicle. It

is the first GOES to fly an SXI-type instrument.

GOES Spacecraft Contractors

The SMS and GOES 1-3 spacecraft were built by Ford Aerospace and Communications Corporation (now Space Systems/Loral). The GOES 4-7 series was built by Hughes Space and Communications (now Boeing Satellite Systems). The GOES 8-12 series was built by Space Systems/Loral. GOES-NO/P/Q are being built by Boeing Satellite Systems.

Hurricane Bret, 1999

As well as the web sites mentioned elsewhere in this brochure, see http://www.oso. noaa. gov/

goes/index.htm, http://goes2.gsfc.nasa.gov, and http://rsd.gsfc.nasa.gov/goes for additional

information on the GOES program and GOES science. For additional copies of this brochure,

please write to: GOES Program Manager, NASA Goddard Space Flight Center, Mail Code 415,

Greenbelt, MD 20771.
33Acronyms and Abbreviations

μm micrometer

μrad microradian

AFB Air Force Base

Alt altitude

CCD Charge Coupled Device

CDAS Command and Data Acquisition Station

CDDF Central Data and Distribution Facility

COSPAS Cosmicheskaya Sistyema Poiska Avariynich

Sudov (Space System for the Search of Vessels

in Distress)

CSPA Charge Sensitive Preamplifier

DCP Data collection platform

DCS Data collection system

DPU Data processing unit

DSN Deep Space Network

ELT Emergency Locator Transmitter

EMWIN Emergency Managers Weather Information

Network

EPEAD Energetic Proton, Electron, and Alpha

Detector

EPIRB Emergency Position Indicating Radio Beacon

EPS Energetic Particle Sensor

ER Eastern Range

ETR Eastern Test Range

EUV Extreme ultraviolet

eV Electron volt

FOV Field of view

fps feet per second

ft feet, foot

GARP Global Atmospheric Research Program

GEM Graphite epoxy motor

GOES Geostationary Operational Environmental

Satellite

GPS Global Positioning System

GSFC Goddard Space Flight Center

HASS High Accuracy Sun Sensor

HEPAD High Energy Proton and Alpha Detector

HV High voltage

Hz hertz

in inch

INR Image Navigation and Registration

ITT A/CD ITT Aerospace/Communications Division

JPL Jet Propulsion Laboratory

keV kilo (thousand) electron volts

kg kilogram

kHz kilohertz

km kilometer

kW kilowatt

LAM Liquid apogee motor

lb pound

LMATC Lockheed Martin Advanced Technology

Center

Acronyms and Abbreviations

LRIT Low Rate Information Transmission

LUT Local User Terminal

m meter

MAGED Magnetosphere Electron Detector

MAGPD Magnetosphere Proton Detector

MCC Mission Control Center

MECO Main engine cutoff

MeV Million electron volts

MHz Megahertz

MLI Multilayer insulation

mps meters per second

NASA National Aeronautics and Space

Administration

NASCOM NASA Communications (Network)

NGDC National Geophysical Data Center

NiH2 Nickel hydrogen

NISN NASA Integrated Services Network

nm nanometer (one-billionth of a meter)

nmi nautical mile

NSF National Science Foundation

NESDIS National Environmental Satellite, Data, and

Information Service

NOAA National Oceanic and Atmospheric Administration

OSR Optical solar reflector

PLB Personal Locator Beacon

PMT Photo Multiplier Tube

PSS Precision Sun Sensor

RCC Rescue Coordination Center

RSC Rescue Sub-Center

RF Radio frequency

SAIC Science Applications International Corporation

SARSAT Search and Rescue Satellite-Aided Tracking

SEC Space Environment Center

sec second

SECO Second Engine Cutoff

SEM Space Environment Monitor

SLV Space Launch Vehicle

SMS Synchronous Meteorological Satellite

SOCC Satellite Operations Control Center

SSD Solid State Detector

SXI Solar X-Ray Imager

UHF Ultra high frequency

USMCC U.S. Mission Control Center

VAS VISSR/Atmospheric Sounder

Vel velocity

VISSR Visible Infrared Spin Scan Radiometer

WEFAX Weather Facsimile

XRP X-ray positioner

XRS X-ray sensor
NP-2001-7-324-GSFC