Commenters were impressed by the tiny radio tags used to follow monarchs, with one noting that the devices weigh just 60 milligrams. They shared information about BluMorpho tags and a phone app that can scan for nearby tags, and one commenter was eager to pass the information along to other monarch enthusiasts. Another marveled that butterflies can cross Lake Michigan without stopping, a journey of roughly 60 to 70 miles. The tracking project prompted interest in how technology can reveal the scale and details of monarch migration.
The conversation also turned to a gardener’s concern about a surge in oleander aphids and a sharp decline in monarch caterpillars. One commenter suggested releasing ladybugs as a way to manage aphids, while another cautioned that ladybugs sold online may come from the western U.S. and could be a poor choice for areas where local species are already struggling. A third recommended growing yarrow, dill, or sunflowers to encourage ladybugs to reproduce naturally, adding that their larvae are especially voracious. The advice thus divided between buying predators for immediate help and fostering locally appropriate populations in the garden.
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The city-building sequence assigns each new building the smallest height equal to the number of earlier buildings it can see. It is unbounded and contains every nonnegative integer, with computational data showing that small heights occur most often. (oeis.org)
The Vera C. Rubin Observatory has identified its first candidate dwarf planet in the solar system. Follow-up observations are needed to confirm its status. (rubinobservatory.org)
A scientist’s past experience with homelessness shapes their perspective and approach to research. Their personal history influences the questions they pursue in science. (science.org)
CAMS’s Methane Hotspot Explorer maps large methane plumes detected weekly by the Sentinel-5P satellite, using machine learning to identify emissions. It estimates plume origins and source categories, but satellite resolution cannot pinpoint facilities, and detections vary with emissions and observing conditions. (atmosphere.copernicus.eu)
The “Boy Born on Tuesday” puzzle asks for the chance that two coin flips were both heads, given a truthful report of at least one Tuesday head. This added information changes the odds in a counterintuitive way, showing why probability problems require careful counting rather than intuition. (win-vector.com)
Chinese researchers developed a catalyst that converts carbon dioxide from Mars’s atmosphere into methanol. The liquid could power equipment and support production of materials, though making it on Mars is only technically feasible to a degree. (scmp.com)
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