Update on September 26, 2023: This puzzler image shows an ephemeral arc spanning a fjord in Greenland. It may have been caused by a wave from a calving iceberg or an underwater plume of freshwater rising to the surface. Read more about the image in our Image of the Day story.
Every month on Earth Matters, we offer a puzzling satellite image. The September 2023 puzzler is shown above. Your challenge is to use the comments section to tell us where it is, what we are looking at, and why it is interesting.
How to answer. You can use a few words or several paragraphs. You might simply tell us the location, or you can dig deeper and offer details about what satellite and instrument produced the image, what spectral bands were used to create it, or what is compelling about some obscure feature. If you think something is interesting or noteworthy, tell us about it.
The prize. We cannot offer prize money or a trip on the International Space Station, but we can promise you credit and glory. Well, maybe just credit. Within a week after a puzzler image appears on this blog, we will post an annotated and captioned version as our Image of the Day. After we post the answer, we will acknowledge the first person to correctly identify the image at the bottom of this blog post. We also may recognize readers who offer the most interesting tidbits of information. Please include your preferred name or alias with your comment. If you work for or attend an institution that you would like to recognize, please mention that as well.
Recent winners. If you have won the puzzler in the past few months, or if you work in geospatial imaging, please hold your answer for at least a day to give less experienced readers a chance.
Releasing comments. Savvy readers have solved some puzzlers after a few minutes. To give more people a chance, we may wait 24 to 48 hours before posting comments. Good luck!