Author: Sabrina Stierwalt, PhD

Dr Sabrina Stierwalt earned a Ph.D. in Astronomy & Astrophysics from Cornell University and is now a Professor of Physics at Occidental College.

Some of my best episodes, in my humble opinion, are inspired by the questions that my daughter asks me. To make it through another heatwave here in southern California, we were borrowing a neighbor’s pool when she suddenly became very concerned about sharks. I assured her there were no sharks in the pool, but she kept re-confirming with me: still no sharks in the pool? How fast would fresh water take out a shark? I asked her how she thought a shark would get in the pool and she matter-of-factly pointed out that someone could drop one in via helicopter.…

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Flossing every day, running more, eating more vegetables—whatever our goals, around four in ten of us will make resolutions to improve ourselves in the new year. But how many actually keep them? One relatively optimistic study that followed a group making new year’s resolutions for six months found that 46 percent were still on track by the end of June. However, a quick google search turns up numerous references to the fact that 80 percent of new year’s resolutions fail by the second week of February. As far as I can tell, these mentions all trace back to a single place: a US News article that…

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Is astrology real? Reading horoscopes is a popular diversion, but is there any science to suggest it means anything? Inspiration finds you if you’re willing to dedicate yourself to a cause.  Problems may arise when you’re tempted by a familiar disruption and your willpower weakens.  Something appearing meaningless may be a lesson to learn.  As many as 70 million Americans read their horoscopes daily. Well, that’s at least according to the American Federation of Astrologers. According to a study done twenty years ago by the Pew Forum on Religion & Public Life, 25 percent of Americans believed that the positions of the…

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As of December 4, 2019, 565 people from 41 countries have gone into space. That’s it. 565 out of more than 7 billion of us currently on this planet. And that’s using the definition of space travel to include any flight over 62 miles or about 100 kilometers. Many of these space travelers are, of course, NASA astronauts. That means they went through a rigorous application and training process. So, what exactly does it take to be an astronaut? Minimum requirements to be an astronaut To be considered for the NASA astronaut program is you must be a U.S. citizen. Dual citizenship…

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Somewhere between Hawaii and the Philippines near the small island of Guam, far below the surface of the water, sits the Mariana Trench, the deepest spot in the ocean. What’s down there? How deep is the Mariana Trench? The Trench sits like a crescent-shaped dent in the floor of the Pacific Ocean, extending over 1500 miles long with an average width around 43 miles and a depth of almost 7 miles (or just under 36,201 feet). At that depth, the weight of all that water above makes the pressure in the Trench around 1000 times higher than it would be in, say,…

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Mariah Carey, Ella Fitzgerald, Bing Crosby, Mozart, Beethoven, Jimi Hendrix, and Yanni. What do these musicians have in common? They’re all said to have perfect pitch. How rare is perfect pitch? If you don’t have it already, can you learn it? What is perfect (or absolute) pitch? Perfect pitch (technically known as absolute pitch) is the ability to identify, without effort, the pitch of a note. Let’s say someone plays a D on the piano. A person with perfect pitch—and the musical training to be able to name the notes—would be able to identify the note as a D without…

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Eerie images from the site of the Chernobyl nuclear disaster still haunt us 30 years later. What is Chernobyl like today? On April 26, 1986, a safety test gone wrong led to an explosion in reactor #4 at the Chernobyl Nuclear Power Plant in Pripyat, Ukraine. (At the time, Pripyat was part of the USSR.) Several factors then conspired to result in an unprecedented, widespread scattering of over 100 radioactive elements into the surrounding towns and cities. First off, RBMK reactors, like the ones at Chernobyl, don’t have containment structures like concrete and steel domes. Second, the fire resulting from the explosion…

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A stronger immune system, more energy, improved endurance, and better stamina … one ingredient promises all of that. Whether it’s as an extract, a pill, or powdered into your coffee, the cordyceps fungus is promoted as a one-stop-shop to cure what ails you. Known as Himalayan Gold because it is often farmed in the Himalayan plateaus, cordyceps has long been used in ancient Chinese and Tibetan medicine for curing diarrhea, headache, cough, rheumatism, liver disease, kidney disease, and much more. But is it too good to be true? What is Cordyceps? As we discussed in a previous episode, the cordyceps fungus grows like a parasite…

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As a parent, I often find myself asking questions I never thought I would ask: How long can someone survive on raisins alone? How did that yogurt get on the ceiling? And so one night, after carefully placing my sleeping baby down in his crib, I stood there holding my breath, noting that I would obviously choose passing out over possibly making the slightest sound that could wake him. I wondered, How long can a person’s body go without oxygen? What sets that limit and why is it that some people can hold their breath for minutes but others only…

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Meteorologists talk not only about what the temperature will be outside, but also what that temperature “feels like.” Why are these numbers sometimes so different? How do meteorologists know what the temperature will feel like to you? Although numeric, temperatures are not universal. Most of us have a sense of what a temperature of 75 degrees Fahrenheit means, but add a brisk wind and you will feel colder. Raise the humidity and the temperature your body experiences feels a lot higher too. Precipitation and cloud cover also play a role in making that 75 degrees a more relative experience. So…

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