21173+5837
- Unique Name: 21173+5837BU 1140AC
- RA: 21 17 18.79
- Dec: +58 36 41.4
- Discoverer: BU
- Discoverer Number: 1140
- Components: AC
- First year: 1912
- Last year: 2003
- Observations: 3
- First position angle: 271
- Last position angle: 270
- First separation: 69.9
- Last separation: 68.2
- Mag first component: 6.4
- Mag second component: 12.6
- Spectral type: B3III
- Primary proper motion RA: -3
- Primary proper motion DEC: -3
- Secondary proper motion RA: -16
- Secondary proper motion DEC: -12
- Durchmusterung:
- Notes: N
