21577+4356
- Unique Name: 21577+4356BTG 9AD
- RA: 21 57 41.80
- Dec: +43 55 41.0
- Discoverer: BTG
- Discoverer Number: 9
- Components: AD
- First year: 2000
- Last year: 2007
- Observations: 3
- First position angle: 86
- Last position angle: 86
- First separation: 38.1
- Last separation: 38.0
- Mag first component: 12.2
- Mag second component: 14.0
- Spectral type:
- Primary proper motion RA: -6
- Primary proper motion DEC: 8
- Secondary proper motion RA: -10
- Secondary proper motion DEC: -3
- Durchmusterung:
- Notes: