There’s no question that we’re entering what some would call a golden age of space exploration – witness India’s recent landing on the south pole of the Moon and so many more ventures beyond the confines of our planet. But in this Wild West environment, there’s one problem that’s not being dealt with sufficiently: trash. University of Arizona astronomer and regular contributor Chris Impey writes that geopolitical rivalries and commercial interests continue to override the problems – and dangers – caused by space debris and waste, including 100 bags of human waste now on the Moon.

Even a casual student of psychology knows that certain parts of the brain are wired to detect danger, an adaptation that was valuable in our species’ early evolution – and still is in reacting to threats – but that can be counter-productive in modern life. Wayne State University psychiatrist and neuroscientist Arash Javanbakht explains how fear functions in people, starting in the “fight, flight or freeze” parts of the brain and extending to different parts of the body. Although we all may feel anxiety and fear in different ways, ultimately emotions originate in the brain, the control center of our physical sensations.

Having read so many of our articles on wildfires, it’s hard for me to look at a dense forested area and not wonder whether it’s in danger of a severe burn because of the build-up of so much “fuel.” Writing about her just-published study, University of Montana fire ecologist Jamie Peeler explains the analysis she and her colleagues did to identify areas in the western U.S. that offer the best payoff from forest thinning efforts, in terms of reducing wildfire risk for communities and carbon emissions. “Forest thinning is like weeding a garden: It removes brush and small trees in dry conifer forests to leave behind space for the larger, older trees to continue growing,” she writes.

Also in this week’s science news:

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An artist’s rendering of debris floating through Earth’s orbit. Petrovich9/iStock via Getty Images

Space junk in Earth orbit and on the Moon will increase with future missions − but nobody’s in charge of cleaning it up

Chris Impey, University of Arizona

Treaties meant to ensure sustainability in space don’t currently regulate private companies, and not every country has signed on to an agreement for sustainable space exploration.
In the face of a perceived threat, your body often activates a fight-or-flight response. George Peters/DigitalVision Vectors via Getty Images

If anxiety is in my brain, why is my heart pounding? A psychiatrist explains the neuroscience and physiology of fear

Arash Javanbakht, Wayne State University

Although emotions like fear and anxiety originate in your brain, they ultimately travel through your body and make your heart race and your stomach twist.
A forest-thinning project in Arizona leaves more open canopy and clearer ground. David McNew/Getty Images

The US is spending billions to reduce forest fire risks – we mapped the hot spots where treatment offers the biggest payoff for people and climate

Jamie Peeler, University of Montana

Forest thinning and controlled burns take away fuel for fires, but the US can only treat so many acres. Which ones to choose?

Invasive species cause billions of dollars in damage worldwide: 4 essential reads

Jennifer Weeks, The Conversation

According to a new UN report, invasive species do more than US$423 billion in damage worldwide every year. Four articles explore examples, from mollusks to poisonous fish.

The US broke global trade rules to try to fix climate change – to finish the job, it has to fix the trade system

Noah Kaufman, Columbia University; Chris Bataille, Columbia University; Gautam Jain, Columbia University; Sagatom Saha, Columbia University

Joe Biden’s ‘buy American’ effort with EVs likely violated World Trade Organization rules that the US helped create. The US has an opportunity now to update the system – if it’s willing to take it.

The US committed to meet the UN’s Sustainable Development Goals, but like other countries, it’s struggling to make progress

Scott Schang, Wake Forest University; John Dernbach, Widener University

Halfway to the SDGs’ 2030 deadline, countries have made progress, but most are struggling to meet all 17 goals. The US is no exception.

Experts alone can’t handle AI – social scientists explain why the public needs a seat at the table

Dietram A. Scheufele, University of Wisconsin-Madison; Dominique Brossard, University of Wisconsin-Madison; Todd Newman, University of Wisconsin-Madison

Industry leaders, scientists and policymakers may see AI’s technical potential, but societies have trouble adapting to revolutionary advances without broad public participation.