NASA News · September 30, 2026
APOD: 2026 September 30 – Arp 78: Peculiar Galaxy in Aries
Where it is in your sky
- Object
- NGC 772 · Galaxy
- Constellation
- Aries
- Best seen
- Evenings from August to December; highest at midnight in October
- Climbs above 20°
- From 51° S to 89° N
- Never rises
- South of 71° S
- What you need
- A small telescope (80–150 mm)
Tonight from your location
From the source
Peculiar spiral galaxy Arp 78 is found within the boundaries of the head strong constellation Aries. Some 100 million light-years beyond the stars and nebulae of our Milky Way galaxy, the island universe is an enormous 200,000 light-years across. Also known as NGC 772, it sports a prominent, outer spiral arm in this detailed cosmic portrait. Tracking along sweeping dust lanes and lined with young blue star clusters, Arp 78’s overdeveloped spiral arm is pumped-up by galactic-scale gravitational tides. Interactions with its brightest companion galaxy, the more compact NGC 770 seen directly below the larger spiral, are likely responsible. Embedded in faint star streams revealed in the deep telescopic exposure, NGC 770’s fuzzy, elliptical appearance contrasts nicely with spiky foreground Milky Way stars.
APOD’s email for image submissions has changed. Please see: APOD Submissions. Tomorrow’s picture: a harvest
From NASA News.
