21040+2841
- Unique Name: 21040+2841HJ 1609AB
- RA: 21 04 00.82
- Dec: +28 40 41.1
- Discoverer: HJ
- Discoverer Number: 1609
- Components: AB
- First year: 1828
- Last year: 2012
- Observations: 14
- First position angle: 40
- Last position angle: 36
- First separation: 5.0
- Last separation: 8.0
- Mag first component: 11.04
- Mag second component: 11.22
- Spectral type: A5
- Primary proper motion RA: -11
- Primary proper motion DEC: -11
- Secondary proper motion RA: -10
- Secondary proper motion DEC: -5
- Durchmusterung: +28 3976
- Notes: