Picture of the Day · NASA
PK 164 +31.1: The Headphone Nebula
2026-05-27
What is a pair of headphones doing in the sky? Today’s image features the Headphone Nebula, also known as PK 164 +31.1 or Jones-Emberson 1. This planetary nebula, the remnant of a dying Sun-like star, faintly occupies an angular region of the Lynx constellation about 1/5th the diameter of the full moon. The red and blue-ish green colors trace hydrogen and oxygen atoms, respectively, that have been excited and ionized by the nebula's central white dwarf. The headphone shape, where two lobes of hydrogen puncture the inner region of oxygen, adds this object to a long list of oddly shaped nebulae. The morphology of such strange nebulae hint at the presence of a stellar or planetary companion, which can stir the material flowing out from the dying star. You can listen to Hubble and JWST sonifications of planetary nebulae through your very own headphones!
via NASA APOD
Key facts
- Discovered by
- K. Reinmuth
- Discovery site
- Heidelberg Obs.
- Discovery date
- 30 September 1921
- Named after
- Arne Asplind, (son of Bror Asplind )
- Alternative designations
- A921 SE · 1927 YD, 1952 DD 2 · 1960 OF, A916 YB · 1921 KF
- Minor planet category
- main-belt · ( outer ) , background
- Observation arc
- 103.03 yr (37,630 d)
- Aphelion
- 3.8813 AU
- Perihelion
- 2.4752 AU
- Semi major axis
- 3.1782 AU
- Orbital period sidereal
- 5.67 yr (2,070 d)
- Mean anomaly
- 86.935 °
- Mean motion
Wikidata facts
- Instance of
- asteroid
- Followed by
- Q158297
- Follows
- 958 Asplinda
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- +45.176
- Orbital period
- +2067.011667064374
Show 3 more facts
Article
959 Arne (prov. designation: A921 SE or 1921 KF) is a background asteroid and slow rotator, approximately 52 kilometers (32 miles) in diameter, located in the outer region of the asteroid belt. It was discovered by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory on 30 September 1921. The X-type asteroid has an exceptionally long rotation period of 123.7 hours. It was named after Arne Asplind, son of Swedish astronomer Bror Asplind (1890–1954).
Orbit and classification