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
- Christian Heinrich Friedrich Peters
- Discovery date
- 31 July 1872
- Pronunciation
- / ˈ b r uː n h ɪ l d /
- Named after
- Brynhildr
- Alternative designations
- A872 OB
- Minor planet category
- Main belt
- Observation arc
- 143.71 yr (52490 days)
- Aphelion
- 3.0183 AU (451.53 Gm )
- Perihelion
- 2.37594 AU (355.436 Gm)
- Semi major axis
- 2.69710 AU (403.480 Gm)
- Orbital period sidereal
- 4.43 yr (1617.9 d )
- Average orbital speed
- 18.08 km/s
- Mean anomaly
Article
123 Brunhild is a stony S-type main-belt asteroid. It was discovered by German-American astronomer C. H. F. Peters on July 31, 1872, and named after Brünnehilde, a Valkyrie in Norse mythology. Brunhild has been mistaken for the non-existent variable star KN Gem.
In 1983, 123 Brunhild was observed photometrically from the Observatoire de Haute-Provence, producing an irregular light curve that showed eight extremes, including two minima and two maxima that were more accentuated than the others. This curve indicates an irregular shape or possibly areas with higher albedo, with a rotation period of 10.04 ± 0.02 hours and a brightness variation of 0.16 ± 0.01 in magnitude.