Important Missions in Spectroscopy History
Launch date: May 23, 1969
Lifetime: 10 years
Energy range: 3 to 750 kev (very "hard" x-rays to gamma rays)
One of the first satellites to detect gamma-ray bursts.
Long lifetime allowed for study of long-term variability of x-ray binaries and x-ray transients.
Co-discovered (with ANS) x-ray bursts.
Launch date: Dec. 12, 1970
Lifetime: Two years
Energy range: 2 to 20 keV
First earth orbiting mission to be entirely devoted to x-ray astronomy.
First comprehensive and uniform all sky survey.
Detected 339 x-ray sources, including binaries, supernova remnants, Seyfert galaxies and clusters of galaxies.
Discovery of the diffuse x-ray emission from clusters of galaxies.
Launch date: August 21, 1973
Lifetime: about nine years
Energy range: 0.5 to 10 keV (x-ray only)
Discovery of several log-period pulsars (e.g., X Per).
Discovery of absorpton dips in Cyg X-1.
Long-term monitoring of pulsars and other bright x-ray binaries.
Observed rapid intensity variability from Cen A.
Launch date: October 15, 1974
Lifetime: About six years
Energy range: 0.3 to 40 kev
Long-term monitoring of numerous x-ray sources.
Discovery of several long-period (minutes) x-ray pulsars.
Discovery of several bright x-ray transients probably containing a black hole (e.g., A0620-00=Nova Mon 1975).
Established that Seyfert I galaxies (Active Galactic Nuclei) are a class of x-ray emitters.
Discovery of iron line emission in extragalactic sources.
Launch date: June 21, 1975
Lifetime: About three years
nergy range: 0.15 Kev to 1 MeV (well into gamma-ray)
Iron-line detection in the x-ray spectra of a cluster of galaxies.
Detection of black-body spectrum from x-ray bursts.
Set upper limit on the polarization of radiation from several x-ray binaries.
Launch date: August 12, 1977
Lifetime: about one year and half.
Energy range: 0.2 keV to 10 MeV
Complete flux-limited High Galactic Latitude Survey.
Measurement of x-ray background from 3 to 50 keV.
Comprehensive catalog of x-ray sources (one for each experiment).
Several hundred optical companions and source classifications based on x-ray source positions.
Monitored variability of a variety of objects from AGNs to x-ray binaries.
Studied aperiodic variability in Cyg X-1 on time scales on a few milliseconds
Discovered the first eclipse seen in a low-mass x-ray binary.
HEAO-2, A.K.A. "EINSTEIN"
Launch date: November 12, 1978
Lifetime: About two and a half years
Energy range: 0.2 keV to 20 keV
First imaging x-ray telescope in space.
High-resolution Solid State Spectrometer (0.5 to 4.5 keV).
First high resolution spectroscopy and morphological studies of supernova remnants.
Recognized that coronal emissions in normal stars are stronger than expected.
Resolved numerous x-ray sources in the Andromeda Galaxy and the Magellanic Clouds.
First study of the x-ray-emitting gas in galaxies and clusters of galaxies revealing cooling inflow and cluster evolution.
Detected x-ray jets from Cen A and M87 aligned with radio jets.
First medium and deep x-ray surveys.
Discovery of thousands of "serendipitous" sources.
Marked a "turning point" in x-ray astronomy. After Einstein, X-ray astronomy is completely established.
Tenma: February, 20, 1983, through November, 22 1985
EXOSAT: May 26, 1983, through April 9, 1986
GINGA: February 5, 1987, through November 1, 1991
ROSAT: 1 June 1990, through 12 February 1999
ASCA: February 20, 1993, through March 2, 2001
RXTE: December 30, 1995, to the present
BeppoSax: April 30, 1996, through 30 April 2002
Chandra: July 23, 1999 (nominal five-year mission)
XMM-Newton: December 10, 1999 (nominal 10-year mission)
SOURCE:High-Energy Astrophysics Science Archive Research Center
Back to Fine-Tuning Astronomy