Update on May 27, 2025: This springtime Landsat image shows snow-covered tundra streaked with wind-blown sediment near Utqiaġvik, Alaska, the northernmost city in the United States. Congratulations to John Christian for being the first reader to identify the location. Read more about the area in “Months in the Midnight Sun.”
Every month on Earth Matters, we offer a puzzling satellite image. The May 2025 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!
My guess is that this is somewhere on the Alaska North Slope, as the outlines in the snow appear similar to the networks of oval lakes and meandering streams one sees there. While it appears things are still mostly frozen, my guess is we are seeing some stream banks that have melted through a recent coat of snowfall. This might expose soil that is then blown by fierce spring winds, leaving the dark streaks in the image.
Frozen Signatures
What scrawled these lines in frozen dust?
Not hands, but wind’s relentless gust—
A sculptor blind yet deft and sure,
Carving forms that still endure.
Sharp ridges rise, then fall away,
Their curves aligned with wind’s ballet.
Not random—these are sastrugi,
Where snow and wind in union lie.
They trace the path of polar breath,
Marking life in seeming death.
No tree, no beast—just snow’s reply
To whispers drifting from the sky.
A satellite with watchful eye
Captured this cold symphony.
From orbit, it records the tale
Of patterns driven by the gale.
Fine grains arranged by force and time,
A frozen memory, vast, sublime.
Each groove a record scientists prize—
A diary beneath the skies.
For though the desert here is white,
Its dunes, like sand, shift day and night.
This is no lifeless wasteland’s art—
It speaks of climate, wind, and heart.
So gaze upon this spectral sea:
A windswept code in purity.
The answer lies in ice and air—
And in the shapes now resting there.
Rivers, air quality from fires, smoke drifting from fires? This is challenging! The base looks to be SRTM… Mostly just commenting so that I can look at other answers. Very fun!
Looks like wind-blown dunes in the Sahara desert.
This looks like a snow-covered plain with a mixture of meandering rivers and small lakes, all frozen. I’m going to guess that this is somewhere like the Old Crow River area in the Yukon. I’m also going to guess the sensor is the Landsat OLI. If I’m correct, the black streaks are shadows, probably produced by very low-angle sunlight striking trees along the river bank during the arctic winter. That a Landsat sensor could capture shadows would be pretty special.
If I can revise my earlier guess, I think the image is of a region just east of Atqasuk, Alaska. The image shows snow-covered meandering rivers and small lakes/ponds. I still think the dark streaks are shadows in high-angle sunlight during arctic winter. I just noticed a similar three streams in Atqasuk 5 minutes after posting my last guess.
Migration of animals across the banks of the frozen river around a low sun angle (maybe late afternoon). The image may be in true colour composite.
For the first look and moment Yellowstone winter after snowing windy period…
You guys are making this challenge very hard. I can only say that this is in Antarctica somewhere…maybe around the Thwaites Glacier?
Vatnajokull National Park, Iceland
I think this is a picture of dunes in a desert. The interesting thing is the formation of the dunes.
Alaska
This satellite image shows wind-sculpted snow formations, most likely sastrugi, in a polar region such as East Antarctica. The striking patterns—sharp ridges, grooves, and sweeping arcs—are the result of persistent katabatic winds shaping the snow surface over time. The sun angle, low on the horizon, casts long shadows that exaggerate the relief of these features, making the topography visible from space. This interplay of light and shadow is crucial for identifying subtle surface textures in remote sensing, helping scientists interpret wind direction, surface roughness, and environmental conditions in otherwise featureless frozen landscapes.