M70
NGC 6681 · Globular cluster in Sagittarius
- Magnitude
- 7.9
- Size
- 8′
- Effective surface brightness
- 20.8 mag/arcsec²
- Best months
- Jun, Jul, Aug
- Declination
- -32°
- Filter
- None (broadband target)
M69's near twin two degrees east, a compact globular in the same low field.
Reachable from mid-northern latitudes (UK, northern US, central Europe) and from the south.
How long with each smart telescope
| Telescope | In frame | Bortle 3 (rural) | Bortle 5 (suburban) | Bortle 7 (urban edge) |
|---|---|---|---|---|
| ZWO Seestar S5010 s subs | 19% | 8 min50 subs | 11 min69 subs | 26 min155 subs |
| ZWO Seestar S50 Pro10 s subs | 10% | 9 min55 subs | 13 min76 subs | 28 min169 subs |
| ZWO Seestar S3010 s subs | 11% | 9 min54 subs | 12 min73 subs | 26 min159 subs |
| ZWO Seestar S30 Pro10 s subs | 6% | 10 min58 subs | 13 min80 subs | 30 min178 subs |
| DwarfLab DWARF 315 s subs | 8% | 11 min46 subs | 16 min66 subs | 39 min155 subs |
| DwarfLab DWARF mini15 s subs | 11% | 8 min33 subs | 11 min46 subs | 26 min103 subs |
| DwarfLab Draco30 s subs | 11% | 15 min30 subs | 15 min30 subs | 21 min43 subs |
| DwarfLab DWARF II15 s subs | 7% | 31 min126 subs | 40 min162 subs | 1 h 20 min322 subs |
| Vaonis Vespera II10 s subs | 9% | 8 min50 subs | 11 min69 subs | 26 min155 subs |
| Vaonis Vespera Pro10 s subs | 8% | 19 min115 subs | 26 min156 subs | 56 min337 subs |
| Vaonis Vespera 310 s subs | 9% | 8 min47 subs | 11 min66 subs | 25 min149 subs |
| Vaonis Vespera Pro 210 s subs | 8% | 18 min109 subs | 25 min149 subs | 54 min322 subs |
| Unistellar eQuinox 24 s subs | 23% | 9 min134 subs | 11 min165 subs | 20 min299 subs |
| Unistellar Odyssey4 s subs | 24% | 44 min666 subs | 52 min778 subs | 1 h 24 min1,266 subs |
| Celestron Origin10 s subs | 16% | 5 min30 subs | 5 min30 subs | 7 min43 subs |
| Celestron Origin Mark II10 s subs | 18% | 5 min30 subs | 5 min30 subs | 10 min60 subs |
Imaging the globular cluster
Globular clusters are point sources packed tight, so they come quickly: the core resolves into stars within a handful of minutes on any smart scope. More time deepens the halo and pulls in the faint outer members. Use short subs so the core does not saturate into a white blob, and no filter.
Per-telescope pages
- How long to image the M70 with the ZWO Seestar S50
- How long to image the M70 with the ZWO Seestar S50 Pro
- How long to image the M70 with the ZWO Seestar S30
- How long to image the M70 with the ZWO Seestar S30 Pro
- How long to image the M70 with the DwarfLab DWARF 3
- How long to image the M70 with the DwarfLab DWARF mini
- How long to image the M70 with the DwarfLab Draco
- How long to image the M70 with the DwarfLab DWARF II
- How long to image the M70 with the Vaonis Vespera II
- How long to image the M70 with the Vaonis Vespera Pro
- How long to image the M70 with the Vaonis Vespera 3
- How long to image the M70 with the Vaonis Vespera Pro 2
- How long to image the M70 with the Unistellar eQuinox 2
- How long to image the M70 with the Unistellar Odyssey
- How long to image the M70 with the Celestron Origin
- How long to image the M70 with the Celestron Origin Mark II