- Astronautics in astronomy--Congresses (10)
- Infrared telescopes--Congresses (7)
- Low temperatures--Congresses (7)
- Optical instruments--Congresses (7)
- Gravity--Experiments--Congresses (2)
- Orbiting solar observatories--Congresses (2)
- Solar activity--Measurement--Congresses (2)
- Sun--Observations--Congresses (2)
- Astronomical instruments--Congresses (1)
- Gamma ray spectrometry--Congresses (1)
- Nuclear counters--Congresses (1)
- Ultraviolet spectrometry--Congresses (1)
- X-ray spectroscopy--Congresses (1)