Mission Overview

Astro B was the second Japanese X-ray astronomy satellite. After launch on February 20, 1983, it was renamed Tenma (Japanese for “Pegasus”). Tenma carried GSFC detectors which had an improved energy resolution (by a factor of 2) compared to proportional counters and performed the first sensitive measurements of the iron spectral region for many astronomical objects.

Lifetime: February 20, 1983 - November, 22 1985
Energy Range: 0.1 keV - 60 keV
Launch Information
Launch Date: 1983-02-20 at 05:10:00 UTC
Launch Vehicle: M-3S-3
Launch Site: Uchinoura Space Center, Japan
Decay Date: 1988-12-17

Trajectory Description
Type: Orbiter
Central Body: Earth
Epoch start: 1983-02-20 05:10:00 UTC

Orbital Parameters
Periapsis 489.0 km
Apoapsis 503.0 km
Period 94.5 minutes
Inclination 31.5°
Eccentricity 0.0010179999517276883

Instrumentation

Payload:
•   Gas Scintillator Proportional Counter: 10 units of 80 cm2 each, FOV ~ 3deg (FWHM), 2 - 60 keV
•   X-ray focusing collector: 2 units of 7 cm2 each, 0.1 -2 keV
•   Transient Source Monitor: 2 - 10 keV
•   Radiation Belt Monitor/Gamma-ray burst detector

Science

Astro B was the second Japanese X-ray astronomy satellite. After launch on February 20, 1983, it was renamed Tenma (Japanese for “Pegasus”). Tenma carried GSFC detectors which had an improved energy resolution (by a factor of 2) compared to proportional counters and performed the first sensitive measurements of the iron spectral region for many astronomical objects.

Summary