21258+3640
- Unique Name: 21258+3640S 790AC
- RA: 21 25 47.02
- Dec: +36 40 02.5
- Discoverer: S
- Discoverer Number: 790
- Components: AC
- First year: 1895
- Last year: 2012
- Observations: 24
- First position angle: 98
- Last position angle: 99
- First separation: 53.9
- Last separation: 53.3
- Mag first component: 5.89
- Mag second component: 10.22
- Spectral type: B0Ib
- Primary proper motion RA: 8
- Primary proper motion DEC: -10
- Secondary proper motion RA: -1
- Secondary proper motion DEC: -16
- Durchmusterung:
- Notes: N D
