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
- Viktor Knorre
- Discovery date
- 4 January 1876
- Pronunciation
- / k ɒ ˈ r oʊ n ɪ s /
- Alternative designations
- A876 AA; 1893 PA;, 1911 HB; 1955 HA1
- Minor planet category
- Main belt
- Adjectives
- Koronidian / k ɒr ə ˈ n ɪ d i ə n /
- Observation arc
- 122.53 yr (44755 d)
- Aphelion
- 3.0181 AU (451.50 Gm )
- Perihelion
- 2.71904 AU (406.763 Gm)
- Semi major axis
- 2.86858 AU (429.133 Gm)
- Orbital period sidereal
- 4.86 yr (1774.6 d )
- Average orbital speed
- 17.80 km/s
- Mean anomaly
Wikidata facts
- Instance of
- asteroid
- Named after
- Coronis
- Followed by
- Q141165
- Follows
- 157 Dejanira
- Parent body
- Sun
- Minor-planet group
- asteroid belt
- Diameter
- +39.025
- Orbital period
- +1773.716168086995
- Image
- 158Koronis (Lightcurve Inversion).png
Show 5 more facts
Article
158 Koronis is a main-belt asteroid that was discovered by Russian astronomer Viktor Knorre on January 4, 1876, from the Berlin observatory. It was the first of his four asteroid discoveries. The meaning of the asteroid name is uncertain, but it may come from Coronis, the mother of Asclepius from Greek mythology. Alternatively, it may come from Coronis, a nymph of the Hyades sisterhood. The Koronis family is named after this asteroid.
From its spectrum this is classified as an S-type asteroid, indicating a stony composition. Photometric observations show a synodic rotation period of 14.206 ± 0.002 hours with a brightness variation of 0.28–0.43 in magnitude. A subsequent study at the Altimira Observatory during 2010 was in agreement with this estimate, yielding a rotation period of 14.208 ± 0.040 hours. Based on a model constructed from the lightcurve, the shape of Koronis resembles that of 243 Ida, an asteroid in the same family, although it is a bit larger.