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
- Y. Väisälä
- Discovery site
- Turku Obs.
- Discovery date
- 16 September 1938
- Named after
- Savonia , (Finnish region)
- Alternative designations
- 1938 SJ · 1925 RL, 1938 SG 1 · 1948 VR, 1951 SV · 1953 GD, 1966 HB · 1976 HZ
- Minor planet category
- main-belt · ( inner ) , background
- Observation arc
- 78.50 yr (28,673 days)
- Aphelion
- 2.4777 AU
- Perihelion
- 1.9019 AU
- Semi major axis
- 2.1898 AU
- Orbital period sidereal
- 3.24 yr (1,184 days)
- Mean anomaly
- 114.29 °
- Mean motion
Wikidata facts
- Instance of
- asteroid
- Named after
- Savonia
- Followed by
- Q140003
- Follows
- Q139972
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- +7.804
- Orbital period
- +1183.998762047107
- Image
- 001494-asteroid shape model (1494) Savo.png
Show 4 more facts
- P61
- Yrjö Väisälä
Article
1494 Savo, provisional designation 1938 SJ, is a stony background asteroid from the inner region of the asteroid belt, approximately 8 kilometers in diameter. Discovered by astronomer Yrjö Väisälä at the Turku Observatory in 1938, the asteroid was later named after the Finnish region of Savonia.
Discovery