Rising probability of an asteroid strike; rainforest resilience; animal consciousness

This week, University of Ferrerra researchers reported on the evolution of European skin, eye and hair pigmentation over the last 45,000 years. A re-examination of Galileo space probe data strongly suggests that Callisto has a subsurface ocean. And a two-dimensional carbon material is reportedly tougher than graphene and resists cracking.

Additionally, an Earth-bound asteroid’s chances of striking the planet rose this week; researchers reported that the Amazon is more resilient than previously believed; and scientists and philosophers jointly developed a new approach to explore animal consciousness:

Nihilist sentiment slightly up

Good news for nihilists—a NASA report says that the chance of asteroid 2024 TR4 striking the Earth in 2032 rose to 3.1%. But it’s a real mixed bag for people standing out on the lawn with arms outstretched awaiting the hammer of the universe, since its size is between 130 and 300 feet, making it a “city killer,” rather than a “planet killer.”

Basically, you’ll have to be standing in exactly the right place to be obliterated by a massive shockwave. Additionally, as astronomers track its approach, the chances of a strike will likely rise before abruptly collapsing to zero, which was the case with asteroid Apophis in 2004, which, for a brief, shining moment (if you’re a nihilist), had a 2.7% chance of striking the Earth, before continuing tracking ruled it out.

On the positive side of the ledger (if you’re a nihilist), its current 3.1% chance of Earth impact sets a new record. NASA says that the danger it poses is not its size, but its velocity; one estimate suggests TR4 could hit the atmosphere at 40,000 miles per hour. It would likely explode in an airburst well above ground level with a force of about 8 megatons. The astronomers have not ruled out the possibility of an impact crater.

Though the chances of an impact are likely to diminish with further observation, NASA says that if they rise to 10%, the International Asteroid Warning Network will issue a formal warning and a recommendation for all U.N. members in threatened areas to “begin terrestrial preparedness.”

Rainforest still damp

Previously, ecologists believed in a “tipping point” argument that deforestation reduces evapotranspiration of water from the soil to the atmosphere, causing a reduction in rainfall. Now, in a new study, researchers are challenging this hypothesis. Noting that earlier modeling studies supported the “tipping point” argument, scientists from the Max Planck Institute for Meteorology addressed important limitations: These studies were based on global climate models using a simplified representation of convection, or else they were based on regional models that don’t apply well to large-scale atmospheric circulation.

Instead, the researchers built the first global simulation to use the global storm-resolving ICON model, and instead of the simplified model of convection incorporated by previous studies, they explicitly resolved convection. They found that precipitation in the Amazon is not as dependent on evapotranspiration as researchers once thought. While evapotranspiration does decline with deforestation, this loss is compensated by changes in large-scale circulation. According to the new model, mean annual precipitation does not change significantly in the Amazon, even after deforestation.

Topic slippery

Sometimes philosophers get involved with scientific research efforts, often to the annoyance of scientists, in order to clarify the ethical domain that legitimate research occupies and to provide new approaches for addressing slippery topics that scientists still struggle with. One big example is the existence of animal consciousness. An international group of philosophers and scientists has just published a new approach to understanding the depths of animal consciousness that attempts to shed light on similarities and differences among living organisms.

The researchers write, “When humans and other animals perform similar behaviors, and when the best explanation for these behaviors in humans involves conscious experience, then that could be considered evidence… of conscious experience in other animals, too.”

They call for an approach that identifies particular characteristics of consciousness, such as the experience of pain, and seeking evidence that those markers are present in other species. Their approach acknowledges that these kinds of markers have limitations—they offer large language models as an example that linguistic behavior alone does not provide strong evidence of consciousness.

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