Learn about Starlink’s unintended consequences for astronomy from astrophysicist Vivienne Baldassare, NASA Einstein Postdoctoral Fellow at Yale University. Then, learn why toilet paper is white.
Learn about Starlink’s unintended consequences for astronomy from astrophysicist Vivienne Baldassare, NASA Einstein Postdoctoral Fellow at Yale University. Then, learn why toilet paper is white.
More information on NEPA Implementing Regulations:
Why toilet paper is white by Ashley Hamer (Listener question from Gerald)
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Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/why-toilet-paper-is-white
ASHLEY HAMER: Season's greetings. We're wrapping up the year with a look back at your favorite episodes of 2020. Enjoy this Curiosity Daily classic, and stay subscribed for brand new episodes starting January 1.
CODY GOUGH: See you in 2021. Hi. You're about to get smarter in just a few minutes with Curiosity Daily from curiosity.com. I'm Cody Gough.
ASHLEY HAMER: And I'm Ashley Hamer. Today, you'll learn about why Starlink has caused some serious problems for astronomers and how you can help from Astrophysicist Vivienne Baldassare who's a NASA Einstein Postdoctoral Fellow at Yale University. We'll also answer a listener question about why toilet paper is white.
CODY GOUGH: Let's satisfy some curiosity. There's an ambitious project underway to launch a network of satellites into orbit to provide satellite internet access around the world. But it's having some unexpected consequences for researchers. In case you haven't heard about this, the project is called Starlink. And today, Astrophysicist Vivienne Baldassare joins us to tell you what the problem is and what you can do about it. Here's our conversation.
ASHLEY HAMER: Let's do the basics. What is Starlink?
VIVIENNE BALDASSARE: Sure. So it is a network of satellites that is being launched by SpaceX and the goal of Starlink is to provide global internet coverage. The proposed network will be composed of something around 50,000 satellites. And to date, they have launched a few hundred.
ASHLEY HAMER: OK. So, I mean, global internet sounds like a great thing. What's the problem? Especially, like what do astronomers have a problem with?
VIVIENNE BALDASSARE: Yeah. So I agree that it does sound great. But it turns out that these Starlink satellites are actually extraordinarily visible from the ground with ground-based telescopes. So there's lots of satellites already up in orbit but the problem with Starlink satellites is that they are brighter than about 99% of the things that are currently in orbit.
So they're super bright and super detectable by ground-based telescopes. And with the sheer number of them that have been proposed to be launched by Starlink and SpaceX, between spacecraft and space debris, there's about 20,000 things orbiting Earth right now.
So we are talking about a big increase in the number of spacecraft around the Earth. And then as I said, they're also brighter than 99% of the stuff that's already up there. And that's just the SpaceX Starlink. Other companies are thinking of launching similar type projects. Ground-based astronomy is coming up to a bit of a crisis.
ASHLEY HAMER: Why are they so bright? I actually didn't know that.
VIVIENNE BALDASSARE: Well, what SpaceX has said is that they were actually surprised by how bright they were. They thought they were going to be fainter than they are. So it was really a shock to everyone that they were so bright and so detectable. But they are and they continue to launch them now even knowing that they are much brighter than they had originally thought.
ASHLEY HAMER: So what does this look like in practice? I mean, like when you're trying to study something with a telescope, what does this look like?
VIVIENNE BALDASSARE: Yeah. So basically, you get a big bright streak across your astronomy image. And there's many examples of this on Twitter from astronomers who have been observing and have had a Starlink satellite go through their image. So you get this big streak of light.
And this has happened from time to time. I've had satellites pass through images that I've taken but the problem now with Starlink is that there will be just such a huge number of them and they're so bright that it'll cause a really big problem instead of this being a rare phenomenon, it'll happen much more often.
And when you get those streaks, it can both-- well, it interferes with the current image that you're taking and then if it saturates your detector, it can also leave artifacts behind on future images that you take. So it can have the potential to disrupt not just the one frame that it passes through but several frames after that.
ASHLEY HAMER: So you mentioned the FCC. And that makes me wonder like, who gives the OK to put this stuff up there? I mean, it seems strange that someone would be able to put something in space without consulting the people who deal with space all the time, right? Which is astronomers.
VIVIENNE BALDASSARE: Yeah. So the FCC gives approval for launching satellites. But there are no regulations around the appearance of satellites once they've been launched. And a kind of analogous situation actually happened with radio astronomy in the 1970s. So there were radio astronomers who were observing and it turned out that the first GPS satellites actually interfered with those radio signals because they were emitting all across the radio spectrum.
And there are now international regulations which try to coordinate those different parts of the radio spectrum to determine who can use what so that it doesn't interfere with astronomy observations. So that's one example where we've been able to put those regulations in place. But right now, there are no regulations surrounding the appearance or brightness of satellites from orbit, and I think that's something that we really need.
ASHLEY HAMER: So I'm going to ask a philosophical question, I guess. So I guess, some people might say that getting in the way of a few astronomical observations is a small price to pay for connecting more people to the internet. So what would you say to that?
VIVIENNE BALDASSARE: I think that that's a totally valid discussion to have and I think that's one that we could have as a society. But I don't think that that's a decision that should be made by a few primarily US-based corporations alone. That's something that, I think, we as a society have to decide and they're going ahead with this plan without consulting with the rest of us. And this is something that impacts our night sky, which is an incredible natural resource that belongs to all of us.
And to me and to many others, it doesn't seem right that the decision to alter it in this way should be left up to a few corporations.
CODY GOUGH: Vivienne told us that SpaceX is aware of the issue with their satellites, and they are working on the problem. They've tested some ways to make the satellites darker, but they haven't released the results yet. And like she said, there are a lot of other companies who could get in the game and create the same problem. Fortunately, there's something you can do to get involved.
Right now, the US Council on Environmental Quality is proposing changes to National Environmental Protection Act regulations. And right now, they're soliciting comments on those regulations, with a deadline of this coming Tuesday, March 10. So if you feel the night sky should be included in assessments of the environmental impact of government projects, then now is the time to make your voice heard.
You can find a feedback form at regulations.gov and we'll put direct links to the forum and resources for learning more in today's show notes. Thanks, again, to astrophysicist Vivienne Baldassare who's a Nassau Einstein Postdoctoral Fellow at Yale University.
ASHLEY HAMER: We got a listener question from Gerald who writes, "Why is toilet paper white? Wouldn't the world save humongous quantities of chemicals and water and energy if we used unbleached natural brown toilet paper?" Great question Gerald. It might seem like the color of toilet paper is just a matter of marketing. And to be fair, it is a little. But that's only a small part of why toilet paper is white.
The bigger reason, well, bleaching paper does more than just make it look pure and clean. That mostly comes down to a polymer called lignin. OK. So paper comes from wood, right? Well, wood has two main components that are important in paper-making. Cellulose-- which makes up the wood's cell walls, and lignin-- which acts as a stiffening agent and cement that holds the cells together.
Lignin is brown but more importantly, the less lignin a paper contains, the softer and more absorbent it is. Softness and absorbency are what most of us want in our toilet paper. And luckily, removing lignin is a major part of the paper making process. That process begins by separating the cellulose fibers from the lignin. That's either using chemicals, if you're using virgin wood, or a mechanical blender type thing if you're making recycled paper.
The longer the pulp spends processing, the more lignin is removed. But this step can never remove all of the lignin. And too much time spent processing can actually degrade the cellulose, resulting in a weaker product. How do you remove more lignin without damaging the cellulose? Bleaching. That's usually done using chlorine dioxide gas, which might sound scary, but it's actually considered a pollution prevention technology. It's hailed by the EPA in the United Nations because it doesn't produce the toxic substances that previous methods did.
The bleaching process does make the toilet paper white. But more importantly, it makes it soft, absorbent, and, let's be honest, nicer to use on your sensitive parts. Now, that doesn't mean that we need to clear cut forests and pollute waterways just to make our behinds comfortable, while it is harder to remove lignin from recycled materials, there are plenty of companies making recycled toilet paper that does the job just fine.
You can also buy TP made from bamboo or sugarcane which are more sustainable than the pine and spruce trees that standard toilet paper comes from. You can also try using a bidet. But whatever you do, don't judge a toilet paper by its color. There's a lot more going on beneath the surface. Thanks for your question, Gerald. If you have a question, then send an email to podcast@curiosity.com or leave us a voicemail on our studio line at 312-596-5208. Stay subscribed to Curiosity Daily and you might even hear your voice on a future episode. One more time, that's 312-596-5208.
CODY GOUGH: Before we recap what we learned today, here's a sneak peek at what you'll hear next week on Curiosity Daily.
ASHLEY HAMER: Next week, you'll learn about new neuroscience research into why yoga can reduce depression, the surprising health differences between brown and white rice, how bumblebees are able to carry 80% of their own body weight, whether binaural beats are worth the hype, and more. OK. So now, let's recap what we learned today.
CODY GOUGH: Ashley, why did you want to talk about Starlink on this podcast?
ASHLEY HAMER: Well, because I follow a lot of scientists online and I see the stuff that they're complaining about and excited about. But people are frustrated about these satellites. I saw so many pictures that were posted of the beautiful night sky with these giant streaks through them. So I wanted to talk to somebody and find out why.
CODY GOUGH: I thought it was excellent. And I left feedback on the government website about the Starlink thing. I said, I think the night sky should be included in assessments of the environmental impact of government projects. It's not a perfect fix, but it does put it on the radar of policymakers that maybe we should pay attention to that sky that we all share.
ASHLEY HAMER: Right. The sky is just as much a part of our world as the forests and the mountains and the water.
CODY GOUGH: Did you leave feedback?
ASHLEY HAMER: Man, I was going to-- I knew--
CODY GOUGH: Ashley.
ASHLEY HAMER: I knew that was going to be a question you're going to ask me and I was like, better do it before you record. And guess what? I didn't do it. I'm going to do it. And the listeners are going to do it too.
CODY GOUGH: That's cool. You have until Tuesday, March 10. It's regulations.gov. You might even see it in the trending regulations area on the left. I just saw it right at the top of the page. Didn't you note the search for it?
ASHLEY HAMER: And in the show notes, we also link to a really handy PDF that tells you how to write a good comment so that people will listen to you. It's published by the government so they know what they're looking for.
CODY GOUGH: Perfect. And I also learned that toilet paper is white because you have to remove the lignin to make it soft and fluffy. And lignin also happens to be brown. So you end up with a white toilet paper. But the bleaching process itself is not particularly toxic.
ASHLEY HAMER: Not as toxic as it used to be.
CODY GOUGH: And hey, baby steps.
ASHLEY HAMER: Yeah. We can just applaud the improvements, right?
CODY GOUGH: Yes, cool. Today's stories were written by Ashley Hamer, Kelsey Dunk, and Mae Rice and edited by Ashley Hamer, who's the managing editor for Curiosity Daily.
ASHLEY HAMER: Today's episode was produced and edited by Cody Gough.
CODY GOUGH: Have a great weekend and join us again Monday to learn something new in just a few minutes.
ASHLEY HAMER: And until then, stay curious.
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