H-NGC2903
Galaxy in Leo
About
A barred spiral in Leo, about 30 million light-years away and around 100,000 light-years across. William Herschel logged it in 1784 as a double nebula, and Lord Rosse later resolved its spiral form. Its core is a starburst fed by gas flowing in along the bar. It is in the Herschel 400.
Imaging tips
- At 1860–3110 mm on APS-C or 2860–4760 mm on full frame, the galaxy spans a third to half of the frame.
- Faint for its size at 22.4 mag/arcsec², so plan hours of broadband data.
- One imager took 120 × 30-second subs (about an hour), unguided, through a light-pollution filter.
- A faint dwarf, UGC 5086, appeared as a fuzzy patch beside the galaxy in that wide-field view.
- Best around January and February; it peaks near 61° altitude from 50°N.
Facts
- Size
- 13′ × 6′
- Magnitude
- 9.0
- Coordinates
- RA 9h 32.2m, Dec +21° 30′
- Framing, APS-C
- 1860–3110 mm
- Framing, full frame
- 2860–4760 mm
- Best months
- Jan, Feb
- Peak altitude
- 62° from 50°N, 77° from 35°N