Subject
- observational astronomy15
- very long baseline interferometry13
- astrographic catalogs12
- surface photometry12
- interstellar medium11
- photographic magnitude11
- supernovae10
- gravitational lensing9
- h ii regions9
- interferometry9
- standard stars8
- stellar ages8
- stellar masses8
- astronomical reference materials7
- extinction7
- radio continuum emission7
- sky-surveys7
- trigonometric parallax7
- astronomy6
- catalogues6
