M3, globular cluster
It has a visual magnitude of +6.19 and an apparent size of 18 arcminutes, and lies about 33,000 light-years from Earth. M3 contains approximately 500,000 stars, most of them old red stars. However, it also hosts a relatively large number of so-called blue stragglers, blue main-sequence stars that appear much younger than the rest of the globular-cluster population.
General information
- Constellation
- Canes Venatici
- Category
- Clusters and stars
- Date
- 10 April 2026
Capture
- Total time
- 1h 45min
- Subframes
- 30s, 120x CLS (bin1) + (30x R + 30x G + 30x B) bin1
- Gain / Offset
- 125 / 30
- Calibration
- 30 flat frames, 30 dark-flat frames, 40 library dark frames, without bias frames
Equipment
- Telescope
- TS102 f/5.6
- Camera
- ASI294MM at -10ºC
- Filters
- CLS and RGB Astronomik
- Mount
- Sky Watcher Wave 150i
- Guiding
- Guide scope 60mm f/4 + ASI220MM, PHD2
- Focuser
- ZWO EAF focuser
- Filter wheel
- ZWO EFW 7pos
Processing and environment
- Processing
- PixInsight 1.9.3
- Acquisition
- NINA
- Location
- l'Ampolla
- Sky
- Bortle 4