Picture of the Day · NASA
NGC 3660 and Burçin's Galaxy
2026-05-26
The upper galaxy might be more photogenic, but the lower galaxy is more unusual. The galaxy up top is NGC 3660, a spiral galaxy similar to our own Milky Way galaxy in that it has several bright blue spiral arms and a central bar of stars, dust, and gas. Captured by chance in the featured deep and colorful image, surprisingly, is SN 2026cff, a supernova found just to the right of the central bar. Farther in the distance is the bottom galaxy, known informally as Burçin’s galaxy, but formally cataloged as LEDA 1000714. The center of this galaxy appears to be an old elliptical galaxy, but it is strangely surrounded by not one but two rings of stars. What created Burçin's galaxy is a mystery and remains a continuing topic of research, but it likely involves the accretion of one or more smaller galaxies.
via NASA APOD
Key facts
- Discovered by
- K. Reinmuth
- Discovery site
- Heidelberg Obs.
- Discovery date
- 7 February 1919
- Pronunciation
- German: [ ˈʊlaː ] , Classically: / ˈ ʌ l ə /
- Named after
- Ulla Ahrens , (observatory donor)
- Alternative designations
- 1919 FA · 1936 SJ, 1949 OF 1 · 1949 PW, 1966 BU · 1966 DM, A912 CA · A919 CA
- Minor planet category
- main-belt · ( outer ) , Ulla · Cybele
- Observation arc
- 100.99 yr (36,886 d)
- Aphelion
- 3.8633 AU
- Perihelion
- 3.2217 AU
- Semi major axis
- 3.5425 AU
- Orbital period sidereal
- 6.67 yr (2,435 d)
- Mean anomaly
Article
909 Ulla is a large and dark asteroid from the outermost regions of the asteroid belt, that measures approximately 116 kilometers (72 miles) in diameter. It is the parent body and namesake of the Ulla family, which belongs to the larger group of Cybele asteroids. It was discovered on 7 February 1919, by German astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany. The X-type asteroid has a rotation period of 8.7 hours and a notably low value for its Jupiter Tisserand's parameter. It was named after Ulla Ahrens, daughter of a friend of the discoverer.
Orbit and classification