AI Insight
Sh2-188, known as the Shrimp Nebula, is a planetary nebula with an unusually fast-moving white dwarf core creating a visible bow shock as it travels through interstellar space at high velocity. The nebula spans approximately half the Moon's diameter in apparent size, making it one of the larger planetary nebulae visible from Earth. The distinctive swirl pattern and bow shock formation result from the white dwarf's rapid motion compressing and brightening interstellar gas along its leading edge, similar to a boat moving through water.
Why it matters
This observation demonstrates how stellar remnants interact dynamically with the interstellar medium and provides insights into the final evolutionary stages of Sun-like stars. The bow shock phenomenon helps astronomers understand the velocities and trajectories of ejected stellar cores through space.
Understand the Science
APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Sh2-188: The Shrimp Nebula
Explanation: What causes the swirl in the Shrimp Nebula? Its high speed is likely. What is sure is that Sh2-188 is one of the larger planetary nebulas on the night sky, by angular size, spanning about half the diameter of the Moon. Moreover, the white-dwarf core — leftover from the Sun-like star that shed its outer atmosphere — is moving unusually fast through interstellar space, creating a bow shock most visible on the upper left that is similar to a boat plowing through water. Although faint, the Shrimp Nebula glows also by compressing and brightening gas on its leading edge. The featured image was taken in the light of hydrogen, sulfur, and oxygen by a backyard telescope in Krakow, Poland and then digitally adjusted to approximate the nebula‘s true colors.
APOD’s email for image submissions has changed. Please see: APOD Submissions
APOD’s main NASA site has moved: From apod.nasa.gov to science.nasa.gov/apod
Tomorrow’s picture: open space
| Date | September 29, 2026 |
|---|---|
| Credit & Copyright | Pawel Piechnik |
| Authors & editors: | Robert Nemiroff, Jerry Bonnell, Cecilia Chirenti, Keighley Rockcliffe |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |
Source: APOD: 2026 September 29 – Sh2-188: The Shrimp Nebula