In this podcast, Cody Gough and Ashley Hamer discuss the following stories to help you get smarter and learn something new in just a few minutes: Why Hasn't the Mars Opportunity Rover Called Home? Mars Rovers Spirit and Oppy on Twitter @MarsRovers When It Comes to Sunscreen, the SPF Isn't as Crucial as You Think This Dr. Seuss-esque Element Could Turn Carbon Dioxide into Fuel Follow Curiosity Daily on your favorite podcast app to learn something new every day withCody Gough andAshley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.
In this podcast, Cody Gough and Ashley Hamer discuss the following stories to help you get smarter and learn something new in just a few minutes:
Follow Curiosity Daily on your favorite podcast app to learn something new every day with Cody Gough and Ashley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.
Full episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/mars-opportunity-rover-update-sunscreen-spf-meanings-turning-carbon-dioxide-into-fuel
[MUSIC PLAYING] CODY GOUGH: Hi. We've got three stories from curiosity.com to help you get smarter in just a few minutes. I'm Cody Gough.
ASHLEY HAMER: And I'm Ashley Hamer. Today, you'll learn why the Mars Opportunity Rover hasn't phoned home, the difference SPF makes when you're picking out sunscreen, and how scientists might be able to turn carbon dioxide into fuel.
CODY GOUGH: Let's satisfy some curiosity.
ASHLEY HAMER: Today's top story is about the Mars Opportunity Rover which we haven't heard from in a while.
CODY GOUGH: Yeah. Where did it go?
ASHLEY HAMER: I--
[LAUGHTER]
I don't know. Nobody knows.
CODY GOUGH: Well, Somebody's got to know. NASA better now.
ASHLEY HAMER: Well--
CODY GOUGH: That's an expensive piece of equipment.
ASHLEY HAMER: I mean, they know it's on Mars. But yeah. But that's--
CODY GOUGH: That narrows it down.
ASHLEY HAMER: We know it's there. So backing up, Opportunity touched down on Mars in 2004. And it was only supposed to last 90 days, but it's actually still alive and kicking or rolling after 14 years.
It's found evidence for running water on the planet, explored a couple of big craters, and even got out of a sand trap. That's a big deal, because its twin rover, Spirit got stuck in one before it died around 2010. Oh. But like I said, we haven't heard from opportunity in several weeks.
Well, actually I don't think we need to worry because it's just because of a dust storm. When I heard dust storm, I thought of the movie The Martian, but it's actually not a lot like that. Opportunity runs off of solar energy, and the dust is blocking a lot of its sunlight. So our favorite martian rover is probably powered down and in safe mode. It's just hunkering down.
The weird thing is NASA's doesn't know why some dust storms are local while some cover basically the whole planet. We do know that dust storms happen more often in the Southern hemisphere when Mars is closest to the sun. That's because carbon dioxide ice at the pole evaporates, which makes the atmosphere thicker and increases the surface pressure. And at the same time, there are bigger swings in surface temperature that generate winds.
NASA says Opportunity should have enough power to stay alive. And they're definitely keeping their eye on the situation. You can actually follow it on Twitter @Marsrovers for updates.
And if you search for the Opportunity Rover on Twitter, you'll find tweets and even fan art from people who are worried about the little guy. You can see some of our favorite tweets in today's article on curiosity.com and on the Curiosity app for Android and iOS even if you don't have a Twitter account. And if you are on Twitter, then be sure to follow @Curiosity.com because we'll let when we hear big news.
CODY GOUGH: You can follow me in actually there too.
ASHLEY HAMER: You can.
CODY GOUGH: Links in the show notes. Ashley, do you wear sunscreen?
ASHLEY HAMER: Of course, I wear sunscreen.
CODY GOUGH: Like all the time?
ASHLEY HAMER: Well, always on my face. I mean, when you're a lady that wears makeup, pretty much everything has SPF in it at this point.
CODY GOUGH: Oh, that's cool.
ASHLEY HAMER: It is cool.
CODY GOUGH: Well, I don't want to makeup, but I do wear sunscreen. And summer's here, and there are a lot of types of sunscreen. But should you buy SPF15 or should you buy SPF70? Well, today in Curiosity we wrote about how sunscreen works. SPF stands for sun-factor protection. I didn't know that.
ASHLEY HAMER: I knew that.
[LAUGHTER]
CODY GOUGH: Of course, you did. Well, companies calculate SPF by comparing the time it takes a person to burn unprotected with the time it takes for them to burn wearing sunscreen. So if it takes you 20 minutes to burn with no sunscreen and use SPF15, then you should theoretically be able to last 15-times longer. 20 minutes times 15 is about 5 hours. So lasting for 5 hours in the sun sounds good.
Well, sunscreen doesn't actually last that long. Sweat, friction, and even the way that sunscreen is formulated can make it wear off. Dermatologists recommend reapplying sunscreen every two hours. So when you think about it time wise, it doesn't really matter whether you get SPF30 or SPF100 because you'll probably have to put it on again before the difference in protection becomes important.
But there is a difference in how much the SPF protects your skin. If a sunscreen is SPF15, it blocks about 93% of UVB radiation. If you double it and get SPF30, then that blocks 97%. So the difference percentage wise is relatively small-- 93 to 97%.
Go from SPF30 to SPF50 and you raise your blockage from 97% to 98%. So only a 1% difference there. So obviously check with your doctor if you think you might have sensitive skin or another condition that puts you at higher risk for skin cancer, because you might need the higher SPF. But there's no major need to beat yourself up at the store trying to figure out which one to pick.
Just remember that for a full body application, you should use a full ounce of sunscreen, which is about a shot glass full of sunscreen. Just remember not to drink it if you pour it into a shot glass. And make sure you put it on 15 to 30 minutes before you head outside so it can settle in. And give yourself a fresh coat every two hours. Summer safety first.
ASHLEY HAMER: My understanding is that most people don't put sunscreen on the right way. And that's really what leaves them susceptible to sunburn. Because everyone wants to just put it on so that you can't see it, but it really needs to be like white. And then it'll dry, and it won't be white anymore. But you need to have it to a point where it's like white on your skin for it to work.
CODY GOUGH: There you go. Stay safe. Play outside.
ASHLEY HAMER: Cody, do you know what bismuth looks like?
CODY GOUGH: Yeah. It's that weird, colorful crystal with purple and green. And it's really cool looking. It's more of when you're a kid and you go in like a museum's gift shop. They have all those tubs of rocks, and the coolest looking one is bismuth.
ASHLEY HAMER: Definitely. It's all rainbow and looks like stairs on it. It's amazing. I didn't know that it's actually in Pepto-Bismol, which is where the Bismol comes from.
CODY GOUGH: Oh, wow.
ASHLEY HAMER: It's actually in a ton of stuff. It's in cosmetics and ammunition and all sorts of things. It's a really unique element. And new research shows that bismuth actually has a property that we can use to turn carbon dioxide into fuel.
Here's the cool stuff about bismuth. It's the most diamagnetic metal, which means it's repelled by magnetic fields instead of attracted to them. It also expands when it freezes like water does even though most other elements contract. And it melts surprisingly easily. So it's a good safeguard against high electric currents and electronics and good fire detection for sprinkler systems.
Well, Joel Rosenthal is a chemistry professor at the University of Delaware. And he's been studying bismuth for a while. He says, bismuth has catalytic plasticity, meaning it can convert one compound into any of several others with just a few tweaks.
And in a new paper, he says his team was able to tune a chemical reaction to convert carbon dioxide into either carbon monoxide or formic acid. Formic acid has lots of industrial uses from preserving food to manufacturing rubber, leather, artificial flavorings, and perfumes. And even cooler, carbon monoxide can be easily turned into gasoline with technology that already exists.
This is huge because chemists usually need to create a new catalyst for every chemical reaction they want to study. But here, they're just using bismuth. And if we could use this technology to take CO2 from the atmosphere and turn it into useful fuels and chemicals, then that could be huge for the environment.
CODY GOUGH: Read about everything we talked about today and more on curiosity.com and on the Curiosity app for Android and iOS.
ASHLEY HAMER: Join us again tomorrow for the Curiosity Daily and learn something new in just a few minutes. I'm Ashley Hamer.
CODY GOUGH: And I'm Cody Gough.
ASHLEY HAMER: Stay curious.
[MUSIC PLAYING]
SPEAKER: On the Westwood One Podcast Network.