Dealing with the health effects of wildfire smoke is a reality for millions of people, but what’s the best way to keep safe? Running air purifiers indoors and wearing masks certainly help, but some gases can get into a building and remain on surfaces such as floors and ceilings.

For a study published on Friday, Colorado State University atmospheric and indoor chemist Delphine Farmer recreated fire smoke in a lab and found that volatile organic compounds can persist for days and months, even after the smoke clears. The solution, she writes, is to “start cleaning” − physically removing the traces of smoke by vacuuming, dusting and mopping.

As you can imagine, much of our newsroom has turned its focus to covering the Israel-Hamas conflict and commissioning stories that can answer questions our readers may have. In this one, University of Colorado Boulder aerospace engineer Iain Boyd explains how Israel’s Iron Dome missile protection system works and how Hamas overwhelmed it with a high volume of rockets. “The Hamas attack will have repercussions for all of the world’s major military powers,” he writes.

If you need a reminder or a pep talk on the importance of resistance training, I suggest reading Mississippi State University exercise physiologist Zachary Gillen’s explanation of the many benefits, particularly for middle-aged and older people. He notes that resistance training does not need to involve traditional weights but can include yoga, Pilates or circuit training with resistance bands.

Also in this week’s science news:

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Martin LaMonica

Director of Editorial Projects and Newsletters
Smoke can get in around windows and doors. AP Photo/Reed Saxon

Wildfire smoke leaves harmful gases in floors and walls − air purifiers aren’t enough, new study shows, but you can clean it up

Delphine Farmer, Colorado State University

Wildfire smoke, even from fires far away, carries potentially harmful gases that, once inside, tend to stick around. An air quality specialist offers an easy, cheap, effective way to deal with it.
Israel’s Iron Dome air defense system launches interceptor missiles to shoot down incoming missiles and rockets. Ilia Yefimovich/Getty Images

Israel’s Iron Dome air defense system works well – here’s how Hamas got around it

Iain Boyd, University of Colorado Boulder

If Israel’s Iron Dome is the best air defense system in the world, how did so many Hamas missiles get through? An aerospace engineer explains it’s a game of numbers.
Resistance training can take many forms and can be individualized to suit a person’s needs as they age. Jamie Grill/Tetra Images via Getty Images

Steep physical decline with age is not inevitable – here’s how strength training can change the trajectory

Zachary Gillen, Mississippi State University

Weightlifting and other forms of resistance training can help stave off loss of muscle mass and other age-related physical decline.

What is a strong El Niño? Meteorologists anticipate a big impact in winter 2023, but the forecasts don’t all agree

Aaron Levine, University of Washington

An atmospheric scientist explains how El Niño works, this year’s oddities and why this phenomenon doesn’t last long.

Horseshoe crab blood is vital for testing intravenous drugs, but new synthetic alternatives could mean pharma won’t bleed this unique species dry

Kristoffer Whitney, Rochester Institute of Technology; Jolie Crunelle, Rochester Institute of Technology

Horseshoe crabs play a unique role in medicine, but they’re also ecologically important in their home waters along the Atlantic coast. Can regulators balance the needs of humans and nature?

What the extreme fire seasons of 1910 and 2020 – and 2,500 years of forest history – tell us about the future of wildfires in the West

Kyra Clark-Wolf, University of Colorado Boulder; Philip Higuera, University of Montana

As the climate warms, devastating fires are increasingly likely. The 2020 fires pushed the Southern Rockies beyond the historical average. Is there hope for the Northern Rockies?

New technique uses near-miss particle physics to peer into quantum world − two physicists explain how they are measuring wobbling tau particles

Jesse Liu, University of Cambridge; Dennis V. Perepelitsa, University of Colorado Boulder

Physicists uncovered a new experiment hidden in old data from the Large Hadron Collider. Using this innovative approach, the team has unlocked an entirely new way to study quantum physics.