21138+3500
- Unique Name: 21138+3500J 3128AB
- RA: 21 13 46.12
- Dec: +34 57 57.1
- Discoverer: J
- Discoverer Number: 3128
- Components: AB
- First year: 1941
- Last year: 2011
- Observations: 9
- First position angle: 50
- Last position angle: 52
- First separation: 4.7
- Last separation: 5.0
- Mag first component: 10.0
- Mag second component: 10.5
- Spectral type:
- Primary proper motion RA: -19
- Primary proper motion DEC: -15
- Secondary proper motion RA: 7
- Secondary proper motion DEC: 18
- Durchmusterung:
- Notes:
