20123+3451
- Unique Name: 20123+3451AG 249AC
- RA: 20 12 18.31
- Dec: +34 51 10.7
- Discoverer: AG
- Discoverer Number: 249
- Components: AC
- First year: 1902
- Last year: 2002
- Observations: 2
- First position angle: 35
- Last position angle: 31
- First separation: 13.0
- Last separation: 13.0
- Mag first component: 7.96
- Mag second component: 14.0
- Spectral type: K2V
- Primary proper motion RA: 16
- Primary proper motion DEC: -7
- Secondary proper motion RA: -2
- Secondary proper motion DEC: -2
- Durchmusterung:
- Notes: