# Tenma

> space observatory

**Wikidata**: [Q54376](https://www.wikidata.org/wiki/Q54376)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Tenma)  
**Source**: https://4ort.xyz/entity/tenma

## Summary
Tenma is a Japanese X-ray space telescope launched on 20 February 1983 from the Uchinoura Space Center aboard an M-3S rocket. Also designated ASTRO-B, it is the second in Japan’s series of X-ray astronomy satellites and is catalogued as COSPAR ID 1983-011A.

## Key Facts
- Launch date: 20 February 1983
- Launch vehicle: M-3S Japanese carrier rocket
- Launch site: Uchinoura Space Center, Japan
- COSPAR/NSSDCA ID: 1983-011A
- Satellite catalogue number (SCN): 13829
- Alternate names: ASTRO-B, Tenma X-ray Satellite Mission
- Instance of: space telescope
- Wikipedia sitelinks: 18 across 10 languages (ca, cs, de, en, es, fr, gl, id, ja, ko)

## FAQs
### Q: What does "Tenma" mean?
A: The name is the Japanese word for Pegasus; the mission is not related to the later Pegasus Tenma satellite.

### Q: When and where was Tenma launched?
A: It was launched on 20 February 1983 from the Uchinoura Space Center in Japan using an M-3S rocket.

### Q: Is Tenma still operational?
A: The provided data do not specify an end-of-mission date; only the launch event is recorded.

## Why It Matters
Tenma extended Japan’s early leadership in high-energy astrophysics by following the Hakucho (CORSA-b) satellite. Carrying sensitive X-ray detectors, it provided astronomers with long-duration observations of variable X-ray sources such as accreting neutron-star binaries and black-hole candidates. Its data improved measurements of X-ray spectra and timing, helping to map the energetic processes that govern compact objects. As the second Japanese X-ray astronomy mission, Tenma demonstrated the reliability of the M-3S launch vehicle and the nation’s ability to build increasingly capable space telescopes, paving the way for later ASTRO series missions like Ginga, ASCA, and Suzaku.

## Notable For
- Second Japanese X-ray astronomy satellite, consolidating Japan’s early presence in space-based high-energy astrophysics
- Launched by the M-3S, one of the few documented flights of this Japanese carrier rocket variant
- Carries the catalogue number 13829, a standard identifier used in satellite-tracking databases
- Recognised under three names—Tenma, ASTRO-B, and Tenma X-ray Satellite Mission—aiding literature searches across languages

## Body
### Mission designation and naming
Tenma is the Japanese word for Pegasus, reflecting the national tradition of naming X-ray satellites after constellations. It is formally designated ASTRO-B, indicating its place as the second mission in Japan’s ASTRO series of astronomy satellites.

### Launch and orbital insertion
The satellite lifted off on 20 February 1983 at Uchinoura Space Center, Japan, aboard the M-3S launch vehicle. The M-3S is a three-stage solid-fuel rocket developed by the Institute of Space and Astronautical Science (ISAS) specifically for scientific payloads. No orbital parameters or mission duration appear in the supplied data.

### Technical identity
Tenma is catalogued internationally as COSPAR ID 1983-011A and NSSDCA ID 1983-011A. The Satellite Catalog Number assigned by the United States Space Force is 13829, a value widely used in two-line element sets for tracking.

### Scientific context
As a space telescope optimised for X-ray observations, Tenma contributed to the study of high-energy phenomena including accretion disks, neutron-star oscillations, and supernova remnants. Its heritage traces back to Hakucho (1979) and forward to Ginga (1987), forming a continuous Japanese presence in X-ray astronomy throughout the 1980s.

## References

1. Jonathan's Space Report
2. Freebase Data Dumps. 2013