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
- 2 September 1929
- Pronunciation
- / ə ˈ k aɪ ə / , / ə ˈ k eɪ ə /
- Named after
- Achaea (Greek region)
- Alternative designations
- 1929 RB · 1955 SZ 1
- Minor planet category
- main-belt · ( inner ) background
- Observation arc
- 86.78 yr (31,696 days)
- Aphelion
- 2.6392 AU
- Perihelion
- 1.7424 AU
- Semi major axis
- 2.1908 AU
- Orbital period sidereal
- 3.24 yr (1,184 days)
- Mean anomaly
Wikidata facts
- Instance of
- asteroid
- Named after
- Achaea Regional Unit
- Followed by
- Q136531
- Follows
- 1149 Volga
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- +7.689
- Orbital period
- +1184.181348137834
- Image
- 001150-asteroid shape model (1150) Achaia.png
Show 3 more facts
Article
1150 Achaia (/əˈkaɪə/); prov. designation: 1929 RB) is a stony background asteroid from the inner regions of the asteroid belt. It was discovered by Karl Reinmuth at Heidelberg Observatory on 2 September 1929. The S-type asteroid has a notably long rotation period of hours 61 hours and measures approximately 7.8 kilometers (4.8 miles) in diameter. It is named for the Greek region of Achaia.
Discovery