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
- Alphonse Borrelly
- Discovery date
- 10 April 1872
- Pronunciation
- / ˈ l æ k ɪ s ɪ s / LAK -iss-iss
- Named after
- Lachesis
- Alternative designations
- A872 GB; 1910 CF;, 1918 UB
- Minor planet category
- Main belt
- Adjectives
- Lachesian ( / l æ ˈ k iː ʃ ( i ) ə n , l ə ˈ k iː ʒ ə n / la- KEE -sh(ee-)ən, lə- KEE -zhən )
- Observation arc
- 143.70 yr (52485 d)
- Aphelion
- 3.2814 AU (490.89 Gm )
- Perihelion
- 2.95390 AU (441.897 Gm)
- Semi major axis
- 3.11767 AU (466.397 Gm)
- Orbital period sidereal
- 5.50 yr (2010.7 d )
Wikidata facts
- Instance of
- asteroid
- Named after
- Lachesis
- Followed by
- 121 Hermione
- Follows
- 119 Althaea
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- +155.132
- Mass
- +5.5
- Orbital period
- +2013.191918999228
Show 4 more facts
Article
120 Lachesis is a large main-belt asteroid. It was discovered by French astronomer Alphonse Borrelly on April 10, 1872, and independently by German-American astronomer Christian Heinrich Friedrich Peters on April 11, 1872, then named after Lachesis, one of the Moirai, or Fates, in Greek mythology. A Lachesean occultation of a star occurred in 1999 and was confirmed visually by five observers and once photoelectrically, with the chords yielding an estimated elliptical cross-section of 184 × 144 km.
This body is orbiting the Sun with a period of 5.50 years and an eccentricity (ovalness) of 0.05. The orbital plane is inclined by 7° to the plane of the ecliptic. Photometric observations of this asteroid were made in early 2009 at the Organ Mesa Observatory in Las Cruces, New Mexico. The resulting light curve shows a synodic rotation period of 46.551 ± 0.002 hours with a brightness variation of 0.14 ± 0.02 in magnitude. It is a very slow rotator with the longest rotation period of an asteroid more than 150 km in diameter. As a primitive C-type asteroid it is probably composed of carbonaceous material.