Rush Hour In Orbit: The Science (and Politics) of Keeping Satellites Safe

Published Jan 7, 2020

Physicist and global security expert Dr. Laura Grego fills us in on the past, present, and future of satellites.

In this episode
  • We learn what it means to "use space better."
  • Does anyone own space?
  • What does it take to keep satellites safe?
Timing and cues
  • Opener (0:00-0:42)
  • Intro (0:42-2:28)
  • Interview part 1(2:28-12:02)
  • Break (12:02-13:15)
  • Interview part 2 (13:15-24:16)
  • Statement on Iran (24:16-28:01)
  • Outro (28:01-29:00)
Related content
Show credits

Editing and Music: Brian Middleton
Research and writing: Jiayu Liang and Pamela Worth
Executive producer: Rich Hayes
Host: Colleen MacDonald

Full transcript

Welcome to the Got Science? Podcast. I’m your host Colleen MacDonald. There’s a lot going on up there in space and that’s our topic today. And like me, I imagine many of you are disturbed by the escalation of tensions between the United States and Iran. Stay tuned after the interview for a statement on the Iran situation by global security expert Dr. Edwin Lyman.

Generations of humans over the millennia have looked up at the night sky and marveled over the vastness of space, the distance of the planets, the cold indifference of the stars.

Those of us alive today might be the only humans who could ever say the night sky is looking back at us.

Thousands of satellites are in orbit around the Earth currently, helping us get through our day: from figuring out what to wear as we check the weather, to navigating real-time traffic on the way to work, to beaming entertainment into our homes when we get back. As a matter of fact, I just checked the Union of Concerned Scientists satellite database… and the latest number as of December 2019 is two thousand, two hundred, and eighteen operational satellites, doing various jobs above our heads.

A satellite database?, you might have just asked yourself. Yes, we have one! It provides a list of these space travelers, along with details about where they’re from and what they’re doing. It’s a nifty resource for the space-curious. We’ll link to it in our show notes or you can simply google satellite database and you’ll find it.

The keeper of the satellite database at UCS is my colleague Dr. Laura Grego, senior scientist with our Global Security program. She does a lot of other things too, although most of them are miles over my head… sorry.

Laura is an expert on space security and missile defense. She joined me to talk about what happens to spare parts and astronaut gloves when they’re left behind in space… how we keep all those satellites from slamming into each other in orbit… and the international committee she serves on that’s trying to keep space safe for the entire planet.


Colleen: Laura, thanks for joining me on the podcast again.

Laura: Oh, Colleen, thanks for having me back.

Colleen: So you're a two-time... Well, I don't want to say "a two-timer." You're not a two-timer. This is your second time on the podcast.

Laura: Yeah, yeah. Yes, this is my second time on the podcast.

Colleen: So Laura, I'm worried about space.

Laura: Well, we are the Union of Concerned Scientists, so we are often concerned about things. So I don't know about worried, but there are some trends happening in space right now, and some of them are pretty...worrisome. And then, also, there are some really big opportunities for improving human health and well-being and prosperity and good things on the Earth by using space better. So we definitely want to make sure that those two things don't interfere, that these sort of worrying, more militaristic uses of space don't interfere with the good things we get.

Colleen: So start by telling us what the different uses are.

Laura: Okay, yeah. So every day, you're using space, like all the time…your cell phone, not only the timing signal from GPS satellites is used to coordinate cell phone traffic, so that whole organizational system kind of relies on this timing signal. And then, of course, people use satellite-derived maps to get around, weather, it coordinates banking transitions, long-distance communications, satellite broadcasts. The ability to be, like, a global species and to be able to talk to people around the other side of the Earth any time you want, or transfer money, a lot of that is routed through satellites and space.

There are satellites that monitor the environment, so it keeps track of the salinity and temperature of the oceans, and it helps us understand how the climate is changing. And on a smaller scale, it helps farmers plan their crops and identify deforestation. There are new satellite services in the public sector which provide rapid-return, frequent views of the Earth. Not super-high resolution, but good enough that people can help keep their governments accountable or mining companies accountable. They say they're not going to flush the stuff in the river, you can see what they're doing.

Colleagues of mine use that kind of imaging to keep track of the North Korean missile program in open-source intelligence. So there's lots of cool stuff you can do. And some of the new things people are thinking about doing are launching big constellations of satellites that would provide broadband internet globally. So to people that don't have easy access to the internet in remote places, they can easily talk to their family abroad, they can send money back and forth. They can get medical advice that they wouldn't have locally or regionally, because it doesn't exist.

Like I have... My husband's brother was in an accident in Somalia, and we got him medical advice here in Boston--it's filled with hospitals and really highly-specialized doctors, and we were able to get them to look at his brain scans, basically, and send the information back and forth, because they didn't have specialists nearby. So lots of good things.

Colleen: So there are commercial uses, scientific uses, military uses?

Laura: Right. Yeah, exactly. So something around 40% of satellites are commercial. So, companies selling a service, like satellite radio, or, you know, the capacity for a business in one continent to have video streams to their subsidiaries in another continent, or to securely transmit a bunch of data, or to broadcast satellite TV and stuff. And then, there's, of course, scientific satellites and civil satellites like, NASA and European Space Agency, and all those types of things. And then, there are military satellites. And that's around 15% of satellites.

Colleen: So who is the air traffic controller for all of these satellites? I mean, space is big, right? We know that, but are they getting crowded out at all? Where exactly are they, and who decides where they can be, and who can be up there?

Laura: Oh, so that's a great question, Colleen. So space is big, right? It is. And satellites...even the biggest satellites are kind of the size of a school bus or something....so they’re…I mean, besides the international space station. But we don't have Death Stars or giant structures, at least in our orbits. They're modestly sized. But there are currently around 2,000 actively-operating satellites. And we know that, actually, because at UCS, we have, for more than a decade, been keeping track of who owns what, what's working up there, what they do, where they are.

And then, there are tens of thousands of tracked pieces of debris, meaning stuff that was up there that used to work, it doesn't work anymore. Or maybe it's like, a bolt fell off a satellite, or an astronaut dropped a glove, or paint flaked off.

Colleen: So this is space debris?

Laura: Space debris, space junk. So stuff that's just floating there. So in contrast to what happens on the Earth, if you drop something, it falls to the ground and it sort of stays there. But if you let go of something in space, it generally continues with the same speed that it was going when you dropped it. And that speed is really high. It can be, like, 30 times the speed of a jet, the fastest ones, right? And they just keep going around and around. And it's not... Especially in low-Earth orbits, which are the closest ones, which are the...so where satellites that are looking at the Earth really are. That stuff is not going in an orderly fashion around a racetrack.

It's like a bunch of crossing orbits, where they're whizzing around. And fortunately, space is big enough, so they're not crashing into each other all the time, and we have a system for knowing where they are. And that mainly comes from the United States military, which has a set of ground and space-based sensors, think radars and optical sensors that look and keep track of what's up there. And it's not exactly traffic control, because it's basically just seeing where stuff is and reporting it. And when they can predict a collision is coming up, like, "You're going to get close to that person. So you two should...better talk, so you don't crash." They sort of issue that guidance.

But the question of if there's a crash coming up, who moves to the left, who moves to the right, whose job is it to move, what if I refuse to move, that stuff has not been sorted out. It's all been, sort of, everybody's self-interest is to keep crashes from happening and it seems to have basically always worked out so far. But right now, as I mentioned, we have around 2,000 satellites that are actively working. Some of these new space uses would require tens of thousands of satellites. And that's the kind of plan that, like, Elon Musk or Jeff Bezos...people who have planned these sort of constellations have tens of thousands in mind.

So that's an order of magnitude bigger than what we have. And the challenge of figuring that out, no one's really prepared to have to take control of that. And it is sort of like, whose job is it?

Colleen: Well, also, can they just put these satellites up there? Do they have to get permission from somebody?

Laura: Yes, they do have to get permission. So there are different types of permission you get. There's some permission for just launching. Launching is a big, pretty dangerous activity. You've probably seen it on TV, you know, the launch of a space shuttle or a space launch. It's big and powerful. So there are accidents that happen, and you want to really have that well-licensed and organized, and done away from people and stuff. So you need permission for launching. And that's generally given by the country that's hosting the launch.

But then, you also have permission to use the communication frequencies. Satellites wouldn't be useful if you couldn't talk with them and exchange information back and forth. And that gets done on a radio frequency...not light, but radio waves, and to kind of organize who gets which part. And so, you're not blasting the same frequency and interfering with each other, there is some coordination that happens. So there's some permission you ask. There's international permission, and then, domestic organization and regulation. So there's a couple layers of that. But that sort of...it was really set up for a different, much slower-paced sort of space environment, not an influx of tens of thousands of satellites.

So you can kind of see some things are already happening. The Starlink satellites...I don't know if you've heard this, but these are part of Elon Musk's idea for a broadband internet satellite constellation. And you can...astronomers can see them in their data while they're sitting on the ground, trying to sensitively observe parts of the sky. You see these streaks of light that come through, because satellites are as bright or brighter than the stuff that you're looking for.

Colleen: So it's interfering with that?

Laura: So it's interfering. So you have to be…you have to have a lot stronger regulatory framework.

Colleen: So is there something like the United Nations for space, or some sort of federation that...?

Laura: Well, it isn't as exciting as the federation. Actually, there is something exactly like the United Nations for space. The United Nations does have some responsibility for it.

[Break]

Colleen: What's an example of something that someone might do, where you would be reprimanded?

Laura: So there's this very valuable part of space that's called the geo-stationary belt. So satellites going around the Earth in low-Earth orbit are zipping around. They go around the Earth every 90 minutes. That's the period they have to stay in to stay up in space. But at a much further distance...at, like 36,000 kilometers, the time it takes to go around its orbit is 24 hours.

So if you line that satellite up at the Equator, and it goes around 24 hours and the Equator goes around 24 hours, it looks like it's just hanging in the sky. So you can imagine that that's useful for satellite TV, for example. When you see people's dishes on their houses, they're not tracking across the sky, trying to find the satellite. The satellite is in one place, and it just sits there. So those positions in geo-stationary orbit, which are these ones that allow you to broadcast really effectively and cheaply, are super valuable. And that gets allocated by this big bureaucratic institution called the ITU, International Telecommunication Union.

So you have to get permission. You say, "I'm going to be in this position broadcasting at this frequency." And they say, "Okay, that's you. That's the one you get." So if somebody were to wander their satellite into your space and start broadcasting at your frequency, sort of bumping you out of the way, that's a big no-no. So that would be something you'd get reprimanded, and you might not get permission to go back up there.

Colleen: So what are some of the...? What would some of the motivations be, on the broadcast level, of nudging into somebody's space? Because you don't have your own permission, and you want to get in on somebody else's signal? Or is there...

Laura: Yeah, I guess so.

Colleen: ...a nefarious reason?

Laura: Well, there are...I guess there are a few reasons. One, you wanted that spot and somebody else got it. And you're like, so what are you going to do about it? So I mean, there are some reasons... Because, as I said, they're valuable, you can sell these services. Another aspect, and this isn't why people do bad behavior, but they kind of... It is really first come, first served up there. And so, the countries that were technically advanced, fastest, have more access to it. It's not really equitable, in that sense. It might all be full by the time you get your country's satellite all sorted out, and you've assembled the money to do it, and you got ready. And it's like, "Oh, there's nowhere for me to go." That's not super fair. People don't usually do that and then get in someone else's way. But there is an element of inequitability.

There are other reasons people do this, and they are more nefarious. Like, there are some satellites that are launched, and they maneuver around, and they sort of intelligence-gather about other satellites. They're just like little spy satellites, like, "I'd like to know more about what my potential adversary's doing up here," "I want to see how they built their satellite," "I want to maybe intercept some of those signals and hear what they're talking about."

So they might not be interfering with the broadcast, but they might be getting close by. And that is definitely...that kind of thing is happening now, and it is definitely of concern amongst countries. They tend to be not quite as strong to condemn each other, because everybody kind of wants to do it.

Colleen: So is that happening on both military satellites and commercial?

Laura: That's a good question, I think for the most part, it's military. There is a specialized technology. The ability to get up close to another satellite is actually not something that most satellites can do. They can maneuver a little bit to get out of the way and stuff like this, but the ability to just approach closely without the other satellite welcoming you, or giving you directions, like, "Here is where I am," that's a specialized technology.

Colleen: So, like, the difference between square dancing and ballet?

Laura: Yeah, maybe. That's a good one. Yeah, more coordination, more technique, more training. Yes. So you can...if you can master that technology, there's lots of things you could do. Like, you could go up to a satellite and repair it, or refuel it if it ran out of maneuvering fuel, or add to it. If you wanted to build some kind of structure in space...and you connect them piece by piece like Legos up there, you need to be able to manipulate. Or if you wanted to be able to bring down dead satellites that couldn't get out of the way on their own, you might build a little space tug that goes up and latches on and de-orbits something.

So that technology can be used in a variety of beneficial, or at least neutral, ways. But if you can get up close to another satellite without that satellite's permission, you can also do things like interfere with it or listen in. And that gets people nervous, because often, that's a military or national security thing. And they obviously don't love that, but again, there is no rule about how close you can get to somebody else's satellite. So...

Colleen: So it sounds like, with all of the potential for many, many more satellites, it seems like there's going to have to be a more concerted effort to control who's doing what.

Laura: Yeah. There's some movement to try to better regulate all satellites and commercial satellites, and have best practices about launching things. Most of that action is happening in the commercial and civil arena, because it's, I think, less controversial. You know, guidelines for new space actors so you make sure everybody understands how to preserve the space environment.

But of interest to me, particularly, and the reason I work on this is from a security point of view, because there's also very little guidance about space for national security uses. And there's a lot of potential for conflict there that I think has not been well-addressed, because countries like the United States, for example, has a very, let's say, global posture. There are 800 military bases all across the world, and the U.S. fights wars in faraway places. And the reason it can do that is, it's all stitched up together by this network, this backbone of satellites, that allows commanders to communicate with troops.

Navigation and timing through the GPS satellites allows precision-guided munitions, you have intelligence and reconnaissance, drones... Drones are basically piloted remotely, often from Nevada, and they are forward-based in the Middle East. And all that stuff, all that communication stuff, goes through satellites. They’re really militarily important, and other countries have some of that capability and see the advantages the U.S. gets and wants more. So China and Russia are doing the same thing, Europe. Lots of countries are pursuing this.

So they have these very valuable satellites that are providing this...what these militaries see as very essential capabilities. But satellites themselves are very fragile. You know, they're not easy to protect, they're not armored. And so, you might imagine that that is a difficult position, to have something so valuable and so vulnerable. And how do you protect it in a conflict? How do I keep somebody from attacking this thing that I value so much? And the fact that it's difficult to protect satellites, one of my concerns is, it just speeds everything up. If you think you're going to lose it, then you're going to use it faster.

So we don't have good guidance about how okay it is to target another country's satellites, or when it... We don't have experience with each other in battle that way, and we don't have a really clear set of rules about weapons in space, and when things are off-limits.

Colleen: So Laura, before you go, I do want to talk about space force. What's up with that?

Laura: So I think when you say "space force," your imagination goes all… all sorts of places, right? And we want to think of, what's the uniform…

Colleen: Absolutely.

Laura: ...right? And if you have a new branch of the military, each of them gets a band. So, what's a space force band going to be? That was one of my questions. And we get, like...gee, I don't know, "Do you get an anthem?" Lots of good, sort of cultural questions that we do want to know the answer to. But that was...so the question is, like, "What is it for, and do we need a space force?"

Colleen: It sounds like it's going to be a very active bunch of people doing something.

Laura: Right. So you're trying to imagine, what are you doing? And you're going, like, "X-wing fighter." And you're thinking weapons in space, and controlling the heavens, and all sorts of things. So the military uses space all the time. It’s really the backbone of what they do, the US military, right? And so they have these satellites that provide intelligence and navigation and targeting and communications, all this stuff. And it's really important to the way the military works, but they're hard to protect. And there are some complaints within the military, like, the Air Force is in charge of most of satellites, and Air Force is more interested in planes than satellites, and satellites aren't getting...space isn't getting its due attention.

So it's mostly this bureaucratic question, like, "How do we re-organize our space activities?" That has been the conversation. And the answer the president gave was space force. And some of that, I think, he just like...probably just liked the sound of it.

Colleen: It does sound good.

Laura: But there is some nugget in there, which is, I think, potentially problematic. So if you create a new branch of the military, that its job is just space. You know, are they going to be content, just safeguarding our navigation satellites and making sure everything work, sort of, Mr. Fix-It type of activities?

Or are they, like many bureaucracies, going to try to collect more resources and advocate for their existence, like, "Defend your life," "Well, we need weapons," and to hype the threat, and to just create momentum towards weaponization, just because the way you set up the bureaucracy. And that would be one problem of a space force, is that it just believes its own hype and kind of gets going.

Colleen: It's a little, gets too big for its britches?

Laura: Yeah, yeah. But my guess is going to be some sort of boring, bureaucratic reshuffling. That's what it looks like, for now.

Colleen: So something like space management, or...?

Laura: Yeah. So there has been...right. So recently, space...

Colleen: The space accountant?

Laura: I know.

Colleen: Well, Laura, thanks for joining me on the podcast.

Laura: You're welcome, Colleen. Thanks for having me.


Today’s podcast was recorded before the escalation of tensions between the U.S. and Iran. So, let me recap: On Friday, January 3rd, The Trump administration killed Iranian Major General Qassem Soleimani in a drone attack in Iraq.
  In response, on Sunday, January 5th, Iran announced it will no longer abide by the technical limits on its uranium enrichment program required by a 2015 nuclear agreement. 
  We asked physicist Edwin Lyman, a senior scientist in the Global Security Program at the Union of Concerned Scientists’ Global Security Program, to weigh in on the consequences of these actions Here’s what Dr. Lyman had to say:

“Iran’s decision to no longer abide by the technical limits on its uranium enrichment program required by the 2015 Iran deal is regrettable, but not unexpected.

“President Trump foolishly set the collapse of the multilateral agreement in motion in 2018 when he unilaterally pulled the United States out of the agreement and reimposed crippling sanctions on Iran, despite repeated confirmation by the International Atomic Energy Agency that Iran was complying with its terms. Sunday’s announcement, presumably in response to the U.S. assassination of Iranian Major General Qassem Soleimani, is the culmination of a series of steps over the past year in which Iran has been slowly and steadily weakening its compliance with various terms of the agreement. “Iran remains a signatory to the Nuclear Non-Proliferation Treaty, which prohibits it from developing nuclear weapons. However, Iran’s uranium enrichment facilities could enable it to produce highly enriched uranium—uranium enriched to greater than 20 percent of the isotope uranium-235, which can be used to make a nuclear weapon. While the Non-Proliferation Treaty does not prohibit Iran from producing highly enriched uranium for peaceful purposes or for naval nuclear propulsion, the 2015 agreement restricted Iran from enriching uranium to greater than 3.67 percent uranium-235.

“The 2015 deal’s numerical limits on Iran’s uranium enrichment program were intended to increase the ‘breakout’ time it would take Iran to produce enough highly enriched uranium to build a nuclear weapon if it were to make the decision to do so.

“The 2015 agreement could not have physically prevented Iran from acquiring nuclear weapons, but it would have provided additional time for the international community to respond before Iran could build a weapon. The extent to which the breakout time will decrease will depend on what Iran does next. Iran has said it will continue to fully cooperate with the International Atomic Energy Agency, which presumably will enable the agency to closely monitor any increase in the number and type of installed centrifuges as well as the quantities of enriched uranium at various levels that Iran produces and stockpiles.

“It is also important to note that Iran has made clear its decision is reversible if the United States ended its nuclear-related economic sanctions, which the 2015 deal required. Instead of ratcheting up pressure, which would give Iranian hard-liners the upper hand and could prod Iran to develop nuclear weapons, President Trump should take immediate steps to diffuse tensions, including recommitting to the terms of the nuclear deal. Only diplomacy—not military action—will make a peaceful resolution possible.”

Return to top

Subscribe: