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Nearly every country represented in the United Nations General Assembly recently voted in favor of promoting world maps that more accurately show the size of various continents. But the UN resolution is unlikely to change how millions of people regularly see versions of 16th-century Mercator maps depicting skewed continent sizes in navigation apps.
On September 4, the African-led resolution attracted 164 votes in favor, with six countries abstaining from voting. Only the United States voted to oppose the resolution after describing it as a “radical ideological project,” according to UN News.
The non-binding UN resolution does not impose map changes on anyone. Instead, it “encourages governments, schools, international organizations, and technology companies to use the Equal Earth projection and other so-called equal-area maps when relative size matters,” UN News reported. The resolution also encourages teaching about the trade-offs that arise from depicting a spherical planet on a flat map.
A fruit fly hunting a piece of rotting fruit or a mate navigates by smell, following plumes of odor. Out in the wild, turbulent air swirls these plumes into a chaotic, broken landscape—dense chemical filaments laced through long stretches of clean air. A fly trying to find the source gets the smell in stutters, from constantly shifting directions, with no guarantee that a next whiff is coming at all.
Scientist had little idea of how fruit flies manage this chaotic signal with a brain the size of a pinhead. For a long time, biologists stood by the “surge and cast” model, which posited that insects solved this with hardwired reflexes. The idea was that, when a fly registers the plume with olfactory neurons in its antennae, it simply flies upwind until it’s gone and then flies side to side attempting to catch it again. But now a team led by Vanessa Ruta, a neuroscientist at the Rockefeller University, has shown that fruit flies do something far more advanced.
The trouble with the traditional surge and cast model is that it struggles to explain how an insect tracks a meandering plume across long distances. Chemical cues floating in the air in the natural environment are often sparse and unreliable. But those same features make the mechanism behind olfactory navigation notoriously difficult to test. "Odors are invisible," Ruta says, "and often they're carried along by turbulent airflow." We’ve got no way of knowing what the animal is smelling from one moment to the next.
New navigation satellites in low-Earth orbit could provide 100 times stronger signal strength compared to GPS and other global navigation satellite systems operating from higher orbital altitudes—enabling greater location accuracy within dense cities, under thick foliage, and even inside buildings. Such signals would also likely prove more resilient to interference at a time when commercial flights, maritime shipping, and even various smartphone apps face increasingly widespread disruption from GPS jamming.
That vision may start to take shape when the first six production satellites of California-based Xona Space Systems are scheduled to launch in October 2026, with early service starting in 2027. Once the full constellation of 258 Pulsar satellites has been launched in the following years, Xona claims that customers will be able to accurately pinpoint their locations anywhere on Earth to within several centimeters.
“That added power means that we can get into that indoor environment that GPS can't get to today,” Adrien Perkins, co-founder and VP of engineering at Xona Space Systems, told Ars. “Our higher power allows you to get into those jamming environments a lot further than you would with GPS by itself.”
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