INTEGRAL

ESA's soft gamma-rayhard X-raysThe higher-energy end of the X-ray band, conventionally above about 10 keV; soft X-rays are below about 2 keV. Hard X-rays penetrate absorbing gas, so they reveal obscured black holes. observatory (2002–2025) combined coded-mask imagingcoded-mask imagingImaging hard X-rays and gamma rays, which cannot be focused, by placing a patterned mask above a position-sensitive detector. Each source casts a shifted shadow of the pattern; deconvolution recovers the sky over a wide field at modest resolution. with IBIS and high-resolution germanium spectroscopy with SPI from 15 keVelectronvoltThe energy an electron gains across 1 volt, 1.602 × 10⁻¹⁹ J. High-energy astronomy labels photons by energy: optical light is about 1.7–3.1 eV, X-rays 0.1–100 keV, gamma rays from about 100 keV to beyond 100 TeV. A 1 keV photon has wavelength 1.24 nm. to 10 MeV, plus the JEM-X X-ray and OMC optical monitors. It mapped 511 keV positron annihilation and ²⁶Al line emission across the Galaxy, surveyed hard X-ray sources, and detected the gamma-ray burstgamma-ray burstA flash of gamma rays lasting milliseconds to minutes, followed by a fading afterglow at longer wavelengths. Long bursts come from collapsing massive stars; short ones from neutron-star mergers. from the GW170817 neutron-star mergercompact binary coalescenceThe inspiral and merger of two black holes, two neutron stars or one of each. The signal sweeps up in frequency and amplitude (a chirp) until the objects merge; its shape gives their masses, spins and distance..

Operator

ESA

Orbit

Highly elliptical Earth orbit

Passband

15 keV – 10 MeV

Launch

17 October 2002

End of science operations

28 February 2025