21390+4940
- Unique Name: 21390+4940HJ 1674
- RA: 21 38 59.64
- Dec: +49 39 57.4
- Discoverer: HJ
- Discoverer Number: 1674
- Components:
- First year: 1828
- Last year: 2003
- Observations: 5
- First position angle: 330
- Last position angle: 326
- First separation: 9.0
- Last separation: 11.4
- Mag first component: 9.43
- Mag second component: 11.5
- Spectral type: A0
- Primary proper motion RA: -6
- Primary proper motion DEC: -2
- Secondary proper motion RA: -5
- Secondary proper motion DEC: -2
- Durchmusterung: +49 3583
- Notes: