21556+2823
- Unique Name: 21556+2823MLB 577AB
- RA: 21 55 37.48
- Dec: +28 23 29.6
- Discoverer: MLB
- Discoverer Number: 577
- Components: AB
- First year: 1899
- Last year: 2010
- Observations: 6
- First position angle: 301
- Last position angle: 300
- First separation: 47.0
- Last separation: 48.8
- Mag first component: 10.57
- Mag second component: 11.1
- Spectral type: F0
- Primary proper motion RA: 3
- Primary proper motion DEC: -13
- Secondary proper motion RA: -6
- Secondary proper motion DEC: -7
- Durchmusterung: +27 4201
- Notes:
