There Are Now Eight Billion People On Earth. What’s Next?

11:31 minutes

the sun rises over planet earth
Credit: NASA

Humankind just hit a big milestone this week: a world population of eight billion people. A hundred years ago, there were less than two billion, and now we’ve more than quadrupled that. But after decades of quick population growth, what will the next few decades hold?

Sophie Bushwick, technology editor at Scientific American, explains this to Ira live from the studio. They also talk about other science news this week, like a new initiative from COP 27 to help transition poor countries away from fossil fuels, an ambitious plan to put solar panels in space, how mental health apps aren’t protecting user data, what the discovery of the earliest cooked meal in history tells us about human evolution, and the very first lab-grown meat to gain FDA approval.

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Segment Guests

Sophie Bushwick

Sophie Bushwick is senior news editor at New Scientist in New York, New York. Previously, she was a senior editor at Popular Science and technology editor at Scientific American.

Segment Transcript

IRA FLATOW: Early Wednesday morning, the successful launch of the Artemis One rocket to orbit the moon.


– 3, 2, 1, boosters and ignition and liftoff of Artemis One. We rise together, back to the moon and beyond.


IRA FLATOW: A big first step toward eventually putting people back on that gray lunar ground. So what lies ahead. Joining me now is Brendan Byrne, space reporter at WMFE in Orlando and host of the Are We There Yet? podcast. Welcome back to Science Friday.

BRENDAN BYRNE: Glad to be here, Ira. Thanks for having me.

IRA FLATOW: Nice to have you. I imagine it was nuts at that launch, right? I heard the shouting and the screaming.

BRENDAN BYRNE: It was bonkers. I keep telling people it was indescribable, which is a terrible thing for a reporter to say, but it was incredible. It was absolutely incredible.

IRA FLATOW: Now, I know there were some tense moments just a few hours before the launch with a leaking valve. I spoke with Jim Frey. He’s NASA’s Associate Administrator for exploration systems development after the launch on Wednesday, and I got his view of the launch.

JIM FREY: So I was in the launch control center, which is actually pretty well protected. The windows rattled, but talking to folks who were on the outside and seeing some of these videos that folks took, it was a pretty intense pressure wave that hit.

IRA FLATOW: How is the mood now?

JIM FREY: The mood is– I don’t even– elated. I probably can’t come up with the right words. That’s a long time coming, the hard work and engineering, and there’s not a lot of launch vehicles that their first launch is successful. So of course, we still have a long way to go with the mission and some milestones ahead of us that we don’t take for granted, but boy, to see that rocket go yesterday was incredible.

IRA FLATOW: Yeah, sending a team in to tighten down some nuts under a partially fueled rocket a few hours before launch, that’s kind of a gutsy move, isn’t it?

JIM FREY: It is, yeah. Actually, I was pretty jealous of the [INAUDIBLE].

IRA FLATOW: [LAUGHS] You wanted to do it?

JIM FREY: I would love to do that. I’m probably more at peace with the hardware than I am with the management stuff. But the great thing was all the procedures that are put in place to do that stuff worked– the safety of the people, giving them clear direction. The fact that within just a few minutes of seeing that leak people understood that, hey, that’s where the leak is and that valve is probably loose and really only be not that far into our launch window, I think, was a great testament to that hard work.

IRA FLATOW: What do you watch for in the coming days?

JIM FREY: First thing we watch for is just, coming off of the launch vehicle, can we get the spacecraft power positive is our term. Basically, can we get the solar rays pointed at the sun and get enough power to keep the spacecraft alive, and we’ve been able to do that. We start firing the engines. There’s a whole series of burns we go through with the engines to make sure they all work.

You have three different sets of engines on the vehicle for control, some of them for boost, some of them– so we try and test all that out and make sure that the temperatures are within range. And then we start doing some of the big maneuvers.

We’ll do some in a few days to insert ourselves into the lunar orbit, and then we’ll sit in that orbit for a few days, be further away from the moon than any human-rated vehicle’s ever been. And then we’ll come back and splash down. So we look for all those kind of milestones in the systems to build up our confidence before we put crew on it the next time.

IRA FLATOW: Yeah, so this is really a test mission before you put people on the rocket.

JIM FREY: Yeah, absolutely. So we’re testing out all these systems. You’re pushing them farther than some of these crewed missions will go so that we’re really stressing them so that we gain confidence before the crew gets on there. Now, it doesn’t mean we take the edge off.

We don’t breathe easier. We just have more confidence that we understand how the systems operate. We still take the same care when we put it together.

IRA FLATOW: Yeah, because, after this launch, it’s going to be, what, a couple of years until you put the crew on. Why such a long time?

JIM FREY: So a few years ago, we made the decision, really, around budget to connect Artemis 1 and Artemis 2 with some of the electronics boxes, meaning we’re going to reuse the electronics boxes from 1 to 2. So one is up there, operating. We’re going to bring it back and recover the vehicle and then bring the vehicle all the way back to the Kennedy Space Center and then get in there, take these boxes out, send them back to the vendor, let them get tested, bring them back, and then put them in the Artemis 2 crew vehicle, which is being built just a couple of miles from where I’m at right now.

And then that will go through the rest of its integration and test. So we have this connection of electronic boxes that puts a little bit of a fixed bar between the missions, and then we just have to get Artemis 2 crew capsule through the rest of its flow and up on top of the launch vehicle.

IRA FLATOW: So what can you hope to learn from Artemis 1 that you’ll bring to Artemis 2?

JIM FREY: So we have a great international partner on this mission that has built the service module, the European service module, that provides the propulsion and cooling and power. We want to learn how does that system function in deep space. This is not like low-earth orbit.

We’re on the other side of the Van Allen belts, so the radiation environment is more complex, the thermal environment with the albedo from the moon, the reflection of the moon, and how that affects the vehicle. So we want to have those kind of points. Do we have the right set points on our parameters? Do we have the right flight rules?

When we fly systems, we come up with flight rules. So when you see the folks in Mission control, they’re working to a set of rules that we’ve made engineering assumptions on to evaluate, and now, as we fly the mission, we want to say, are we too stringent? Are we not stringent enough?

Probably the thermal is definitely something I’d highlight, the propulsion elements, and then the crew capsule. That crew capsule has a lot of systems in it that have to function with the crew in it next time, and we’ll hope to learn some of that.

IRA FLATOW: Yeah, because you have to maneuver that capsule around, don’t you, like we haven’t done since Apollo days.

JIM FREY: That’s right. Yeah, so we have, I mentioned, the three types of propulsion systems on there. We also have a guidance, navigation, and control system that helps us look for the star fields to see where we are in space. We have to fire the engines at precise times. You will do an engine firing on the far side of the moon, where we’re not even in communication with the vehicle. So there’s a lot of things that we have to do for the first time.

IRA FLATOW: At what point do you say, hey, we can relax, we’ve got what we needed to get out of this flight?

JIM FREY: Probably when the ship docks in San Diego.


JIM FREY: When, a, because our objectives are to test all of our systems in space and the flight environment, and that started with the launch. And it’s going on right now with Orion. We want to test the heat shield coming back in, and we want to recover the vehicle. So with those three major objectives, I’ll feel better when that vehicle is sitting in the well deck of the Navy ship.

IRA FLATOW: And looking forward, what is the timing for the rest of the mission? When might we see people walking on the moon again in a very large sense, in a projection sense?

JIM FREY: So Artemis 2 is followed by Artemis 3. There’s not the same connectivity between 2 and 3 with the reuse of the hardware, so we’re hoping for Artemis 3 at the end of ’25. We have to build a human lander for that mission, and we have to build new spacesuits for that. So there’s even more hardware coming online.

And then we’re looking at Artemis 4, which will be the first flight to our mini space station around the moon in the late ’26, early ’27 time frame. And then we’re going to start going every year from there on out.

IRA FLATOW: Well, Jim Frey, thank you, and good luck to all of you there.

JIM FREY: Thank you very much. Well, I hope you all stay tuned in what’s going on with Orion.

IRA FLATOW: That was Jim Frey, NASA’s associate administrator for exploration systems development. Sitting here, talking with me and listening to that interview, was Brendan Byrne. He reports on space for WMFE in Orlando and hosts the podcast Are We There Yet?

Brendan, interesting conversation. We are now a couple of days into the mission. Where is the spacecraft now, and what is it doing?

BRENDAN BYRNE: So I’m taking a look at the telemetry right now. It’s 195,000 miles away from Earth and about 123,000 miles away from the moon. And then the cool part about where it’s at now is that it’s being influenced more by the moon’s gravity than the Earth’s gravity, so that’s like a really incredible milestone for a new vehicle, the first vehicle designed for humans since, as you mentioned, the Apollo program in 1972.

So that’s where it’s at. It’s testing out all those systems is, as Jim mentioned. They’re testing some of the systems out inside. There’s actually this really neat experiment happening inside the capsule. Engineers hooked up an Alexa, just like you would have at home that you talk to, to a Webex and a tablet, and this is going to be used for future autonomous astronauts to communicate back to Earth.

But there’s no internet, so they’re testing out all of these different systems in deep space and how you can communicate back to Earth because that’s something that’s going to be really important is to be able to reach back to Earth when you’re this far away. So that’s happening inside the capsule now.

IRA FLATOW: Now you’ve triggered everybody’s Alexas across the country.

BRENDAN BYRNE: I’m sorry. I apologize.


I apologize, everyone.

IRA FLATOW: And the rocket didn’t just have this one spacecraft, right? There were a bunch of tiny CubeSats on board. What are they for?

BRENDAN BYRNE: Yeah, so I think CubeSats are one of the coolest developments in aerospace engineering. So you take what used to be these massive satellites, and you’re able to break them down into these really, really, really tiny spacecraft, like the size of a tissue box.

And there are 10 of these that got deployed just shortly after Orion was making its trip to the moon. And they’re not just experiments that are looking at the moon. They’re going to be looking at our Earth, our sun, and even a near-earth asteroid. But one of the really cool ones that’s on here is it’s got a strain of yeast. So these are live cells that are going to be living in deep space.

And there’s a set of these yeast cells on the International Space Station, and we have them here on Earth. And scientists will be able to compare how this deep-space environment, the radiation that astronauts may be exposed to on these deep-space missions, are going to affect the DNA of these yeast cells, which we can extrapolate and look to see how it might affect us, or humans, when they’re out there. So that’s really cool.

There’s also some sensors that are looking for the minerals that are going to be on the surface of the moon. Scientists are really excited that there’s water underneath the surface that we can use for fuel for future missions. And so these little tiny CubeSats are doing really big work, uncovering all of these things in deep space.

IRA FLATOW: Let’s go to the phones to Harvey in Orlando. Great spot to be in Florida, Harvey.

HARVEY: Yes, it is. And I just– I’ve got maybe a little bit different perspective. I was a teenager when the Apollo missions started going off to the moon, and unfortunately, I was in the audience when we heard that Apollo 1 had burned up on the pad during a test. And the triumph that has come out of that tragedy is just incredible.

But I’ve got a little bit different perspective because I was able to listen to the issues and all the controversy about should we be doing this. I don’t think there’s any question now that we should be, and I’m glad that we are. But having seen the Apollo missions go and all that we got out of that and all that NASA has benefit mankind as a result has just been astounding.

But this, now going forward again with Artemis, is just incredible. I’ve got some interesting aspects of that because I was listening to the differences between what I remember from the Saturn missions and when the Saturn V B took off, it was an extremely intense popping sound, and I was pretty close.

With the Artemis– and I assume this is because of the solid rocket boosters– it was more of a continuous roar, but it was more tactile. When it hit you in the chest, it was like you’re inside of a bass drum, and it was just pounding incessantly. And it was just– it was incredible, to be listening to this and tears streaming down my face. I was just– I was amazed.


HARVEY: Last week, week this red crew that went out, I don’t think too many people remember that there was another red crew that went out a long time ago and locked down some nuts on another rocket before it took off to the moon. That was Apollo 11, but there was a crew that went out there and had to lock it down so that Armstrong and his crew, Buzz Aldrin and Collins, could go to the moon. So this is the second time that a group has gone out to lock down some hydrogen leaks.

IRA FLATOW: Well, Harvey, thank you for your reflections and you remembrances, and good luck to you and everybody else in Florida.

HARVEY: Good deal. Go Artemis.

IRA FLATOW: There you go. Brendan Byrne, what do you think? That is one excited observer, I think.

BRENDAN BYRNE: Yeah, yeah, and there was plenty of more just like Harvey out there, and he’s right. That sound it was– it’s a great way to describe it. It was percussive, and it was from those solid rocket boosters.

And I think one of the coolest things about the solid rocket boosters that Harvey’s talking about is night turned in today. You could actually see the blue sky at 1:00 in the morning when those things lit up. It was pretty wild.

And to Harvey’s point about the red team, most rockets have used a red team like that. It’s been called different things over the years. I think it was called the ice team for shuttle days, but they’ve been deployed to do that. It’s very, very dangerous work but very important work, so the folks of the red team of all the different rockets, from Apollo to ULA’s Atlas V to the Space Shuttle, they all have those red teams in place to do that kind of work.

IRA FLATOW: They must have some kind of toolbox they take.

BRENDAN BYRNE: Yeah, right.


IRA FLATOW: Let’s go to David in Milwaukee. Hi, David. Oh, did we lose David? Oh, we just lost David. I guess what he’s asking– and we might have covered this a little bit– how does Artemis, Brendan, fit in with the– he was wondering on Mars. Does it fit in with any plans for going back to Mars at all?

BRENDAN BYRNE: It does, and you even heard with that launch commentator counting it down, saying, this is one step getting us closer to Mars. Learning how to live and work in deep space is going to be imperative if we’re going to go to places like Mars. This has been– these Artemis missions have been described to me as camping in your backyard before for you hike the Appalachian Trail.

You want to work out all those kinks when you’re closer to home, learn to live and work in deep space for a short period of time before you go even further. I mentioned that there’s water on the surface of the moon. Part of NASA’s plans to get to Mars is to set up the moon as a base for fuel.

You can take that water and separate it into hydrogen and oxygen. We all know very well that SLS uses hydrogen propellant. You can use that to refuel your rocket from the moon to get you to places like Mars. So the Artemis missions are imperative if we want to get to places like Mars and deep space.

IRA FLATOW: A tweet from Mark in Madison who says, how much of the old Apollo knowledge and tech is being dusted off for Artemis?

BRENDAN BYRNE: Quite a bit. A lot of the Apollo tech is being used all over the space flight programming. For instance, the parachutes that bring the crew capsules back home from the International Space Station that SpaceX and Boeing use, those are inspired by Apollo engineering. But there’s a lot of also Space Shuttle legacy hardware in the SLS. those are RS-25 engines. Those four engines on the core stage came from the Space Shuttle Program, so there’s a lot of legacy hardware and knowledge in this program.

IRA FLATOW: Something that kind of flew under the radar this week because of Artemis was testing out a new kind of heat shield on Mars. There were– they came up with something new. Can you talk about that?

BRENDAN BYRNE: I think you’re referring to the heat shield that ULA launched–


BRENDAN BYRNE: –recently. Yes, this is an inflatable heat shield. And from all accounts– of course, I was focused on Artemis, but the accounts that I read that everything went very well on that one. So a heat shield is extremely important, so it’s good to have a few more in your arsenal.

IRA FLATOW: Let’s go to Rich in New Smyrna Beach, Florida. Hi, Rich.

RICH: Hey.

IRA FLATOW: Hey, go ahead.

RICH: –afternoon. How are you all doing?


RICH: Hey, I was wondering, Brendan, what– with all the– I’m in New Smyrna Beach. I get to see the launches all the time, walk out in the front yard. We’ve got so many satellites going up with SpaceX and NASA and DOD. How do they keep from hitting one another?

BRENDAN BYRNE: [LAUGHS] That’s a very good question.

RICH: Are there crosswalks or bike paths?

BRENDAN BYRNE: It’s actually a very good question and something that is becoming more and more of an issue, of this collision avoidance. The Department of Defense is working on it. There’s all sorts of organizations that are calling on this. When Artemis launched, they actually had to calculate what window this crosswalk, as you mentioned, that it could actually launch in that it wouldn’t hit anything.

This is not like a standard satellite that kind of goes into the flow of what’s already in orbit. It’s punching through that flow. So they actually did had to calculate where everything is in orbit, and as more and more stuff gets up there, things die. Things could crash into one another, creating even more debris. So space traffic and space junk and space debris avoidance is a really big issue, and it’s something that a lot of agencies want to get on top of now before there’s something catastrophic that happens in space.

IRA FLATOW: Hope that answers your question. Thanks for calling. The Artemis program isn’t just NASA. It has involvement with the European Space Agency and Canada and other nations, too.

BRENDAN BYRNE: That’s right. Yeah, a lot of these agencies are helping build some of the hardware that’s going to be going there. There’s going to be an international crew on these Artemis flights. We’re going to have other than just NASA’s astronauts there, and Gateway, which Jim Frey spoke about a little bit, will be also built by different countries. The parts will be built by different countries and different commercial entities as well.

But also some other countries have their own plans to go to the moon. China has announced plans to send three uncrewed missions to the moon. Russia has signaled it wants its own moon program. So the moon is going to be a very busy place in the next few years.

IRA FLATOW: All right, we’ll be watching and hoping you’ll help us keep track of it, Brendan.

BRENDAN BYRNE: I’d be more than happy to, Ira. You know I’m happy to chat space with you anytime.

IRA FLATOW: I know, and we could go on all day.



IRA FLATOW: Brendan Byrne, space reporter at WMFE in Orlando, host of Are We There Yet? That’s a great question. Are we there yet, podcasts? Thanks for being with us today.

BRENDAN BYRNE: Anytime, Ira. Thank you.

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