The cosmos, the final frontier, the galaxy beyond: Our collective fascination with outer space has always been strong. But with companies and public figures now dedicating huge sums of money to space exploration, it seems a new kind of space race has been born. In this episode of The Active Share, Hugo sits down with Chris Impey, an astronomer, educator, and author, to discuss the potential economic, environmental, and geopolitical ramifications of space exploration.
Comments are edited excerpts from our podcast, which you can listen to in full here.
What drew you to astronomy?
Chris Impey: I started as a physicist, as physics is the gateway to astronomy. Astronomy is sort of like applying physics outward.
What are the specific areas of astrophysics you've focused on? Are there some you feel proud to have been a part of?
Chris:
I've focused on extragalactic astronomy, or cosmology, and was able to make contributions in two areas. One was the study of extremely faint, feeble galaxies, or those that haven't converted their gas into stars. We try to do a census of what the universe contains, counting all the atoms and materials, but we only look at the bright things. We follow the starlight.But you can miss unevolved galaxies that haven't turned their gas into stars. I was trying to get a full census of the dim and bright galaxies so we can measure the matter of the universe.
I then became interested in active galaxies, or quasars, which are normal galaxies with a supermassive black hole in the center. Black holes are black, but the area around them is an incredible particle accelerator. They can outshine an entire galaxy by a factor of 1,000.
How has the role of technology in astronomy changed?
Chris:
Astronomy is a discovery science, where a lot of things we find were not predicted. That's what makes it fun. But it's also technology driven. When I was a Ph.D. student, the biggest telescopes I used were six meters long. Today, we're building a generation of 20- to 30-meter telescopes.The technology to make thin mirrors and large telescopes with incredibly accurate optics drives the field. Because when you study the distant universe, your photons starve. Some of the galaxies are so far away that only one photon arrives every second. It's a feeble amount of light and means we always want bigger telescopes.
The detector technology has also improved. People probably don't know that charge-coupled devices (CCDs)âthe devices in your phone that take picturesâare just consumer-grade, mass-produced versions of the pioneering detectors astronomers used in the â60s and â70s.
How much of the technological innovation is about making better telescopes?
Chris:
The field is always hungry for more telescopes and photons. The new telescopes are being built by a consortium of universities, countries, and national governments, but there's private money involved, too. Some of the world's biggest telescopes at Mount Wilson Observatory, Mount Palomar Observatory, and Yerkes Observatory in Chicago were funded by philanthropy.And there are many billionaires out there who are interested in science and astronomy. Yuri Milner has put $100 million into the Search for Extraterrestrial Intelligence (SETI) Institute. Bill Gates (Trades, Portfolio) has invested in these things, too. Astronomy draws technology gurus who appreciate pure science.
What about access? How do these telescopes and other technological advancements get divided up?
Chris:
There's sharing, but it's brutal. In Arizona, we make mirrors for our own telescopes, and then we sell them to other people. The Giant Magellan Telescope currently being built in Chile is a 22-and-a-half-meter telescope, but we'll only get 10% of the time on that, even though our contribution was the mirrors. Other universities in the consortium will have to raise money and put cash on the table.There are various ways time is divvied up, but it's hard to get. This is still true of the Hubble Space Telescope, where there are eight times more proposals than time available. And it's also a wild cardâyou may get three nights in July, but if they're cloudy nights, you'll have to come back next year. You don't get a dispensation for the weather.
What is the role of computer power in astronomy?
Chris:
Astronomy is a computationally intensive field in two ways. People think about science as mashing together theories and observations. But there's a third leg of the stool, which is computation and simulation. We've learned a lot about the universe by simulating aspects of it on computers.Understanding our complicated universe is demanding of central processing units (CPUs) and computer power, as is data reduction. Surveys being done by new telescopes will generate tens of terabytes of data per night. And because another few tens of terabytes will be generated the next night, we must parse through this data in real time because we want to be alerted if something's changing, if a supernova just went off, or if an exoplanet was moving.
But the ironic thing about astronomy data is that most of it is noise. When we're observing distant galaxies, most of the pixels in your image are just dark sky. We must sift out the small fraction of pixels where something interesting is happening. Data filtering is a challenge, but we can now use artificial intelligence (AI) to help.
How is AI impacting astronomy?
Chris:
AI and machine learning are having an impact on almost every field of science. The people who try to detect gravitational waves with big detectors like the Laser Interferometer Gravitational-Wave Observatory (LIGO) are using AI to try to filter out subtle signatures of the early universe or black holes merging.We need to use machine-learning methods to not just find the things we know but the things we don't know. But how can we anticipate an interesting phenomenon that we've never seen before? Machine learning helps with that because it can identify something that's potentially interesting without you having specified it beforehand.
Do you think we're in a new space race?
Chris:
It's an extraordinary time for space exploration. Two years ago marked the first time private companies had more launches to Earth's orbit than world governments, eclipsing that of the United States, Russia, and China in terms of space exploration.The value of the private space industry hit half a trillion dollars last year and is projected to double every three or four years. But none of these billionaire investors, such as Jeff Bezos and Elon Musk, are making money yet; their space programs are loss leaders. They're investing for a future that hasn't yet materialized, but they're innovating and creating.
What do you think is the motivation behind these programs?
Chris:
I think there are economic motivations behind Jeff Bezos' Blue Origin and Elon Musk's SpaceX. They are businessmen who have run successful companies, and so they have an economic model. SpaceX has partnered with NASA at a time when the United States couldn't put an astronaut in orbit after the space shuttle was retired, receiving multibillion-dollar contracts to resupply the space station.Elon Musk is also aware of the resources on the Moon and Mars. He has his eye on an actual economic model for the future, but he's driven by this visionary thing.
Similarly, Jeff Bezos has an interplanetary, Star Trek-like vision. Some commentators have even noted how he has been trying to make himself look like his hero, Jean Luc Picard. He has a misty, romantic vision while thinking of a real plan to make money, mine resources, and set up an economic enterprise in space.
Why do you think developing countries like India want to go to the Moon?
Chris:
For India, there's national pride associated with being a spacefaring country, and they should be proud. India has a very impressive technical workforce, but it also has very good space scientists and has developed impressive capabilities from a standing start.But the current Indian government is mostly concerned with national pride, as there's no obvious economic benefit for a still-developing country to engage in space activity. So, to say that India is sitting at a table with just a handful of countriesâRussia, China, and the United Statesâthat have been to the Moon and might go to Mars is a big deal.
Is space an enabler of a decentralized world?
Chris:
Space is like the Wild West. It's essentially unregulated, and the legal backdrop is almost nonexistent. There have only ever been two United Nations (UN) treaties that have dealt with spaceâthe Outer Space Treaty of 1965, which dealt with weapons in space and said that countries couldn't own the Moon, and the Moon Treaty of 1979, which talked about ownership but wasn't signed by any spacefaring power.But these treaties don't answer some of today's most pressing questions, and neither talk about commercial entities or private individuals.
The UN does have a working group that's released nonbinding guidelines for dealing with space junk, liability issues, and other conflicts. But until the major powers sign a new treaty, these guidelines have no teeth. Each country has its own interests, and they don't always overlap.
There's also growing concern that China, whose space program is so entwined with its military-industrial complex, might put weapons in space. We've already seen countries shoot down their own satellites just to test anti-satellite technology. When the Chinese and Russians did that, they created thousands of pieces of space debris, any of which could take out a satellite or space station.
How much risk is there that space debris could wipe out things like GPS or affect the Earth's climate?
Chris:
The amount of space debris is getting rapidly worse. Everyone benefits from low-Earth orbit activity, but no one is incentivized to take care of problems that arise from that activity. The sheer number of satellites or objects in low-Earth orbit is doubling every couple of years, and we're heading toward the possibility of 100,000 objects in orbit by the end of this decade.The collision rate is also going up. All the stuff already in orbit is degrading. Every collision creates pieces that collide with other pieces. In 1979, former NASA scientist Donald Kessler wrote a paper that argued that the increase of space debris will render low-Earth orbit unusable. Back then, it was just a theoretical calculation, but now, people are wondering if it could happen. Today, astronauts at the space stations must shelter in the central hub every month because of a possible impact.
What do you think of space mining? Are there meaningful resources we can extract and bring back to Earth?
Chris:
If you judiciously select one of the near-Earth asteroids half a kilometer in size, you would have roughly $2 trillion worth of precious metals, as well as a similar number of rare, valuable Earth commodities.We have the technology to mine. NASA knows how to steer things in space and attach rockets to asteroids. We could bring an asteroid into orbit and then mine it at leisure. But nobody has determined how much it will cost to deliver the material to Earth. I think mining asteroids is feasible, but the devil is in the details.
Is a future for humankind off-Earth a possibility?
Chris:
I think off-Earth habitation on viable, self-contained bases will happen, but it won't happen right away. We forget space is an extremely hostile, unforgiving environment. We were not made to be in space, and it's too expensive to ship things to the Moon, let alone Mars.But the good news is that the technology to do so exists. We can take Martian soil and use electrochemical methods to turn it into slump block to make a hardened shelter for protection against cosmic rays and radiation. We can also take that same soil and extract water from it, and then separate the water into hydrogen and oxygen and make rocket fuel. All the things we need, assuming we can grow food, are there.
Another piece of this is 3D printing. There will be robots and 3D printing behind many of these first settlements without having to involve large crews of people. But Mars and the Moon are different beasts. It takes eight months to get to Mars and eight months to get back, all on a spaceship that would need almost two years' worth of food, water, and supplies. Getting to Mars for the first time is a huge undertaking. The Moon is much more manageable at only a week away.
Then there's the geopolitical angle. We know that the Chinese have done some impressive things in the last few years. They're close to completing a space station that will be done around the time the International Space Station may be de-orbited. Their space program is growing at the rate of their economy, and they're still investing a huge amount of money. They want to show that they are the world's great superpower of the future. That means a lot of things on Earth, but it also means being off Earth, too.
If you were invited, would you go to Mars?
Chris:
I don't know if I'd go to Mars. It's a huge commitment and extremely risky. But I would go on Richard Branson's quarter-million-dollar, zero-gravity flight or go to the Moon.You serve on the advisory council of Messaging to Extraterrestrial Intelligence (METI). Is there life elsewhere besides Earth?
Chris: METI is an offshoot of SETI, launching in 1959 at the Radio Observatory in Virginia. It's an experiment using radio telescopes to listen for signals that have an artificial origin or don't have a natural, astrophysical cause.
It's also an intellectual exercise that asks, âWhat message would you send that could be meaningful to an alien of unknown function and form?â That's challenging because we can't assume language or culture. Biology may be different, too.
One simple answer is to send out mathematical theorems or prime number sequences to show that we understand mathematics (if we assume mathematics is universal).
Before Stephen Hawking died, he famously said we shouldn't message aliens because they might be malignant. But the few METI experiments that have been done hold little proximate danger because the targets are hundreds or thousands of light-years away. It would be centuries or millennia before we would even make contact.
It's a numbers game. One of astronomy's great successes in the last few decades is the discovery of exoplanets, or planets around other stars. There are about 5,800 confirmed exoplanets, and we can reliably project that number across the Milky Way.
We also know that many of these exoplanets are Earth-like. They could have liquid water, a local energy life source from their star, and carbon-rich material. With potentially 10 billion to 20 billion habitable worlds in the galaxy, it seems implausible that none of them ever developed biology.
The real estate of time is interesting, too. If you look around the galaxy, the earliest Earth clone could have formed 8 billion years before the Earth. We know the Earth formed well into the history of the universe, so it's statistically unlikely that there is no other life out there or that we're the first creatures to attain our level of intelligence and technology. These potential signals are worthwhile things to listen for in the hope of making contact.