21028+4551
- Unique Name: 21028+4551KUI 104CD
- RA: 21 02 40.75
- Dec: +45 53 05.1
- Discoverer: KUI
- Discoverer Number: 104
- Components: CD
- First year: 1934
- Last year: 2000
- Observations: 9
- First position angle: 104
- Last position angle: 96
- First separation: 2.8
- Last separation: 2.0
- Mag first component: 7.82
- Mag second component: 13.4
- Spectral type: K2
- Primary proper motion RA: 404
- Primary proper motion DEC: 141
- Secondary proper motion RA:
- Secondary proper motion DEC:
- Durchmusterung: +45 3371
- Notes: N
