Encyclopedia Astronautica
HEAO



heao.jpg
HEAO
Credit: NASA
American x-ray astronomy satellite. 3 launches, 1977.08.12 (HEAO 1) to 1979.09.20 (HEAO 3). The 3 satellites of the High Energy Astronomical Observatory program surveyed the celestial sphere for X-ray sources and gamma and cosmic ray phenomena.

HEAO 1 was primarily a survey mission, dedicated to systematically mapping the X-ray sky every 6 months. HEAO 1 performed almost 3 full celestial surveys and discovered 1500 new X-ray sources. HEAO 2 (also named Einstein) was the world's first orbiting imaging X-ray telescope and returned detailed quasar images and discovered that Jupiter and Earth emit X-rays. The satellite also made over 5,000 targeted observations and discovered several thousand "serendipitous" sources that fell within the field of view of its imaging instruments. HEAO-3 was designed to detect cosmic ray particles and gamma-ray photons to further the understanding of the strength and extent of interstellar magnetic fields, the distribution of interstellar matter, and the stellar nucleosynthesis process which has created the heavy elements contained in most ordinary matter. All three of the High Energy Astronomy Observatories were regarded as highly successful. The total cost of the program was about $250 million. HEAO 1 re-entered 3/15/79, HEAO 2 re-entered 3/25/82, and HEAO 3 re-entered 12/7/81.

The spacecraft was 3-axis stabilized. Fixed solar panels generated 600 watts and recharged NiCd batteries (24 AHr). The aluminum honeycomb structure used passive thermal control. The hydrazine propulsion system had 110 kg fuel and 6 dual thrusters. S-Band communications used omni antennas. The attitude control system provided arcminute pointing accuracy and arcsecond attitude determination.

Payloads for HEAO 1 were:

  • A1 - Large Area Sky Survey experiment (LASS) - covered the energy range 0.25 to 25.0 keV
  • A2 - Cosmic X-ray Experiment (CXE) - designed to study the large scale structure of the galaxy and the universe, yielding high quality spatial and spectral data over the energy range 2-60 keV
  • A3 - Modulation Collimator (MC) - designed to measure positions of X-ray sources with sufficient precision to identify optical and/or radio counterparts
  • A4 - Hard X-Ray / Low Energy Gamma Ray Experiment.

HEAO 2 carried an X-ray telescope sensitive over the approximate energy range 0.2-3.5 keV. The telescope focused energy on one of four instruments:

  • High Resolution Imaging (HRI) - a digital X-ray camera which provided high spatial and temporal resolution in the 0.15-3.0 keV energy range
  • Imaging Proportional Counter (IPC) - a position sensitive proportional counter sensitive between 0.4-4.0 keV
  • Solid State Spectrometer (SSS) - a cryogenically cooled lithium-drifted Si(Li) detector with a range between 0.5-4.5 keV
  • Bragg crystal spectrometer (FPCS)

. HEAO-2 also carried the Monitor Proportional Counter (MPC), which monitored the 1-20 keV X-ray flux of the sources being observed by the telescope, as well as a Broad Band Filter (BBFS) spectrometer and an Objective Grating Spectrometer (OGS).

HEAO 3 carried a gamma ray spectrometer with 4 cryogenically cooled germanium detectors, each with an energy range of 50 keV to 10 MeV.

AKA: High Energy Astronomical Observatory.
Gross mass: 3,000 kg (6,600 lb).
Height: 9.00 m (29.50 ft).
First Launch: 1977.08.12.
Last Launch: 1979.09.20.
Number: 3 .

More... - Chronology...


Associated Countries
See also
  • Atlas The Atlas rocket, originally developed as America's first ICBM, was the basis for most early American space exploration and was that country's most successful medium-lift commercial launch vehicle. It launched America's first astronaut into orbit; the first generations of spy satellites; the first lunar orbiters and landers; the first probes to Venus, Mars, Mercury, Jupiter, and Saturn; and was America's most successful commercial launcher of communications satellites. Its innovative stage-and-a-half and 'balloon tank' design provided the best dry-mass fraction of any launch vehicle ever built. It was retired in 2004 after 576 launches in a 47-year career. More...

Associated Launch Vehicles
  • Atlas The Atlas rocket, originally developed as America's first ICBM, was the basis for most early American space exploration and was that country's most successful medium-lift commercial launch vehicle. It launched America's first astronaut into orbit; the first generations of spy satellites; the first lunar orbiters and landers; the first probes to Venus, Mars, Mercury, Jupiter, and Saturn; and was America's most successful commercial launcher of communications satellites. Its innovative stage-and-a-half and 'balloon tank' design provided the best dry-mass fraction of any launch vehicle ever built. It was retired in 2004 after 576 launches in a 47-year career. More...

Associated Manufacturers and Agencies
  • NASA American agency overseeing development of rockets and spacecraft. National Aeronautics and Space Administration, USA, USA. More...

Bibliography
  • McDowell, Jonathan, Jonathan's Space Home Page (launch records), Harvard University, 1997-present. Web Address when accessed: here.
  • JPL Mission and Spacecraft Library, Jet Propulsion Laboratory, 1997. Web Address when accessed: here.
  • Lockheed Martin Coporation, Atlas Family Fact Sheets, September 1998.. Web Address when accessed: here.
  • McDowell, Jonathan, Launch Log, October 1998. Web Address when accessed: here.

Associated Launch Sites
  • Cape Canaveral America's largest launch center, used for all manned launches. Today only six of the 40 launch complexes built here remain in use. Located at or near Cape Canaveral are the Kennedy Space Center on Merritt Island, used by NASA for Saturn V and Space Shuttle launches; Patrick AFB on Cape Canaveral itself, operated the US Department of Defense and handling most other launches; the commercial Spaceport Florida; the air-launched launch vehicle and missile Drop Zone off Mayport, Florida, located at 29.00 N 79.00 W, and an offshore submarine-launched ballistic missile launch area. All of these take advantage of the extensive down-range tracking facilities that once extended from the Cape, through the Caribbean, South Atlantic, and to South Africa and the Indian Ocean. More...
  • Cape Canaveral LC36B Atlas V, Atlas launch complex. Atlas Centaur launch pad, in service from 1964 until the retirement of the launch vehicle. More...

HEAO Chronology


1977 August 12 - . 06:29 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC36B. LV Family: Atlas. Launch Vehicle: Atlas Centaur SLV-3D. LV Configuration: SLV-3D Centaur AC-45 / Centaur D-1AR 5025.
  • HEAO 1 - . Payload: HEAO A. Mass: 2,720 kg (5,990 lb). Nation: USA. Agency: NASA Huntsville. Class: Astronomy. Type: X-ray astronomy satellite. Spacecraft: HEAO. Decay Date: 1979-03-15 . USAF Sat Cat: 10217 . COSPAR: 1977-075A. Apogee: 447 km (277 mi). Perigee: 429 km (266 mi). Inclination: 22.7000 deg. Period: 93.40 min. Summary: High Energy Astronomical Observatory; surveyed sky in X-ray band. Spacecraft engaged in research and exploration of the upper atmosphere or outer space (US Cat B)..

1978 November 13 - . 05:24 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC36B. LV Family: Atlas. Launch Vehicle: Atlas Centaur SLV-3D. LV Configuration: SLV-3D Centaur AC-52 / Centaur D-1AR 5032.
  • HEAO 2 - . Payload: HEAO B. Mass: 3,150 kg (6,940 lb). Nation: USA. Agency: NASA Huntsville. Class: Astronomy. Type: X-ray astronomy satellite. Spacecraft: HEAO. Decay Date: 1982-03-25 . USAF Sat Cat: 11101 . COSPAR: 1978-103A. Apogee: 548 km (340 mi). Perigee: 526 km (326 mi). Inclination: 23.5000 deg. Period: 95.40 min. Summary: High Energy Astronomy Observatory. Spacecraft engaged in practical applications and uses of space technology such as weather or communication (US Cat C)..

1979 September 20 - . 05:28 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC36B. LV Family: Atlas. Launch Vehicle: Atlas Centaur SLV-3D. LV Configuration: SLV-3D Centaur AC-53 / Centaur D-1AR 5033.
  • HEAO 3 - . Payload: HEAO C. Mass: 3,150 kg (6,940 lb). Nation: USA. Agency: NASA. Class: Astronomy. Type: X-ray astronomy satellite. Spacecraft: HEAO. Decay Date: 1981-12-07 . USAF Sat Cat: 11532 . COSPAR: 1979-082A. Apogee: 503 km (312 mi). Perigee: 487 km (302 mi). Inclination: 43.6000 deg. Period: 94.50 min. Summary: High Energy Astronomy Observatory; cosmic, gamma ray measurements. Spacecraft engaged in practical applications and uses of space technology such as weather or communication (US Cat C)..

Home - Browse - Contact
© / Conditions for Use