21590+3422
- Unique Name: 21590+3422COU 840
- RA: 21 59 02.27
- Dec: +34 22 35.2
- Discoverer: COU
- Discoverer Number: 840
- Components:
- First year: 1972
- Last year: 1999
- Observations: 9
- First position angle: 64
- Last position angle: 64
- First separation: 0.9
- Last separation: 1.1
- Mag first component: 10.79
- Mag second component: 11.35
- Spectral type:
- Primary proper motion RA: -34
- Primary proper motion DEC: -29
- Secondary proper motion RA: -34
- Secondary proper motion DEC: -29
- Durchmusterung: +33 4396
- Notes: