21005+5709
- Unique Name: 21005+5709STI2557
- RA: 21 00 28.17
- Dec: +57 08 04.1
- Discoverer: STI
- Discoverer Number: 2557
- Components:
- First year: 1917
- Last year: 2012
- Observations: 4
- First position angle: 121
- Last position angle: 131
- First separation: 8.1
- Last separation: 8.1
- Mag first component: 11.9
- Mag second component: 12.5
- Spectral type:
- Primary proper motion RA: -1
- Primary proper motion DEC: 4
- Secondary proper motion RA: 8
- Secondary proper motion DEC: -10
- Durchmusterung:
- Notes:
