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
- C. H. F. Peters
- Discovery date
- 12 August 1883
- Named after
- Saint Barbara ?
- Alternative designations
- A883 PA, 1942 RL 1 , 1953 RE,1975 XP
- Minor planet category
- Main belt
- Observation arc
- 131.26 yr (47944 d)
- Aphelion
- 2.97153 AU (444.535 Gm )
- Perihelion
- 1.79939 AU (269.185 Gm)
- Semi major axis
- 2.38546 AU (356.860 Gm)
- Orbital period sidereal
- 3.68 yr (1345.7 d )
- Average orbital speed
- 19.28 km/s
- Mean anomaly
- 16.9454 °
- Mean motion
Wikidata facts
- Instance of
- asteroid
- Named after
- Saint Barbara
- Followed by
- 235 Carolina
- Follows
- 233 Asterope
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- +45.476
- Orbital period
- +1344.84043886537
- Image
- Asteroid Barbara (artist's impression) (eso0904a).jpg
Show 5 more facts
Article
234 Barbara is a main belt asteroid that was discovered by German-American astronomer Christian Heinrich Friedrich Peters on August 12, 1883, in Clinton, New York. The object is orbiting the Sun with a semimajor axis of 2.385 AU, a period of 3.68 years, and an eccentricity of 0.25. The orbital plane is inclined by 15.37° to the plane of the ecliptic. It is classified as a stony S-type asteroid based upon its spectrum. The mean diameter of this object is estimated as 45.6 km. It has a rotation rate of 26.5 hours, or a little over a day. It is possibly named for Saint Barbara, patron saint of mathematicians.
Observations of light curves and stellar occultations suggest the surface exhibits large concave areas. Polarimetric study of this asteroid reveals anomalous properties that suggests the regolith consists of a mixture of low and high albedo material. This may have been caused by fragmentation of an asteroid substrate with the spectral properties of CO3/CV3 carbonaceous chondrites. It is the prototype for a class of asteroids called "Barbarians" that display a strong infrared absorption band at 2μm, which is a characteristic of an FeO–enriched spinel mineral. Multiple other examples of this class have since been discovered.