Subject
- galaxy classification systems7
- h i line emission7
- spectroscopy7
- wide-band photometry7
- young stellar objects7
- early-type stars6
- h alpha photometry6
- proper motions6
- stellar distance6
- x-ray sources6
- astrometry5
- astronomical object identification5
- co line emission5
- emission line stars5
- galaxy kinematics5
- giant stars5
- polarimetry5
- ultraviolet astronomy5
- late-type stars4
- radio spectroscopy4
