Sextans A - Dwarf galaxy in the constellation Sextans
The dwarf galaxy Sextans A lies on the outskirts of the Local Group and is known for its active star formation. The prominent blue regions consist of young, hot giant stars and compact star clusters that have formed relatively recently. The bright reddish emission nebulae indicate areas of ionized hydrogen (H II regions) where new stars are being born. In the annotated version of the image, all H II regions identified by Hodge et al. (1994) are labeled, as well as the only known planetary nebula in Sextans A to date.
Against the background of a multitude of distant galaxies, Sextans A appears as a cosmic laboratory of stellar evolution - a dynamic place in intergalactic space despite its small mass.
Chosen as NASA Astronomy Picture of the Day on May 29th, 2025 and Amateur Astronomy Photo of the Day on May 25th, 2025.
| Date: | 01.03.-26.04.2025 |
| Optics: | Planewave CDK 14 with Televue 0.8x reducer |
| Aperture: | 350 mm |
| Focal Length: | 2050 mm |
| Camera: | QHY268M |
| Exposure: | L:R:G:B 60:32:30:30 x 600 s Hα:OIII 123:118 x 600 s |
| Location: | Gemsbock Observatory, Rooisand Desert Ranch, Namibia |
| Processing: | PixInsight, Photoshop |
| Diameter: | 8,500 light years |
| Distance: | 4.2 million light years |
