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
- H. Goldschmidt
- Discovery site
- Paris
- Discovery date
- 9 September 1860
- Pronunciation
- / ˈ d æ n eɪ . iː /
- Named after
- Danaë (Greek mythology)
- Alternative designations
- 1953 RL 1 · A917 SM
- Minor planet category
- main-belt · ( outer ) , background
- Adjectives
- Danaëan / d æ n eɪ ˈ iː ə n /
- Observation arc
- 151.67 yr (55,398 days)
- Aphelion
- 3.4798 AU
- Perihelion
- 2.4840 AU
- Semi major axis
- 2.9819 AU
- Orbital period sidereal
Article
61 Danaë (/ˈdæneɪ.iː/) is a stony (S-type) asteroid in the outer asteroid belt's background population, approximately 84 kilometer in diameter. It was discovered by French astronomer Hermann Goldschmidt on 9 September 1860, from his balcony in Paris, France. Goldschmidt was ill when asked to name the asteroid, and requested his fellow asteroid-hunter Robert Luther to name it instead. Luther chose to name it after Danaë, the mother of Perseus in Greek mythology. Danaë was the first asteroid to have a diacritical character in its official name.
The asteroid is orbiting the Sun with a period of 5.15 years and is rotating on its axis once every 11.45 hours. In 1985, a study of lightcurve data suggested that Danaë may have a moon. If so, the main body would be an ellipsoid measuring 85 km × 80 km × 75 km (53 mi × 50 mi × 47 mi), and the moon would orbit 101 kilometres (63 mi) away, measuring 55 km × 30 km × 30 km (34 mi × 19 mi × 19 mi). The density of both would be 1.1 g/cm.