21183+3456
- Unique Name: 21183+3456BU 289AC
- RA: 21 18 18.20
- Dec: +34 55 36.2
- Discoverer: BU
- Discoverer Number: 289
- Components: AC
- First year: 1874
- Last year: 2012
- Observations: 10
- First position angle: 270
- Last position angle: 252
- First separation: 5.0
- Last separation: 12.7
- Mag first component: 9.13
- Mag second component: 13.9
- Spectral type: F8
- Primary proper motion RA: 28
- Primary proper motion DEC: 9
- Secondary proper motion RA:
- Secondary proper motion DEC:
- Durchmusterung:
- Notes: