21055+5340
- Unique Name: 21055+5340BU 680AC
- RA: 21 05 30.82
- Dec: +53 40 05.5
- Discoverer: BU
- Discoverer Number: 680
- Components: AC
- First year: 1885
- Last year: 2007
- Observations: 12
- First position angle: 34
- Last position angle: 33
- First separation: 23.4
- Last separation: 20.8
- Mag first component: 8.7
- Mag second component: 10.9
- Spectral type: A0
- Primary proper motion RA: 7
- Primary proper motion DEC: 7
- Secondary proper motion RA: 1
- Secondary proper motion DEC: -6
- Durchmusterung:
- Notes: