21015+6643
- Unique Name: 21015+6643HU 959
- RA: 21 01 32.33
- Dec: +66 42 33.2
- Discoverer: HU
- Discoverer Number: 959
- Components:
- First year: 1904
- Last year: 2009
- Observations: 24
- First position angle: 153
- Last position angle: 161
- First separation: 1.5
- Last separation: 1.3
- Mag first component: 8.62
- Mag second component: 9.6
- Spectral type: A2
- Primary proper motion RA: 4
- Primary proper motion DEC: -15
- Secondary proper motion RA: 4
- Secondary proper motion DEC: -15
- Durchmusterung: +66 1350
- Notes: