21209+4127
- Unique Name: 21209+4127HO 156
- RA: 21 20 53.71
- Dec: +41 26 31.4
- Discoverer: HO
- Discoverer Number: 156
- Components:
- First year: 1885
- Last year: 1991
- Observations: 10
- First position angle: 45
- Last position angle: 50
- First separation: 1.7
- Last separation: 2.2
- Mag first component: 7.69
- Mag second component: 11.29
- Spectral type: G5
- Primary proper motion RA: -14
- Primary proper motion DEC: -21
- Secondary proper motion RA: -12
- Secondary proper motion DEC: -21
- Durchmusterung: +40 4496
- Notes: