Planetary Radio: Space Exploration, Astronomy and Science - Exploring Black Holes and Supernovae With NuSTAR

Episode Date: March 11, 2014

Principal Investigator Fiona Harrison provides an X-ray tour of some of the universe's most fascinating objects, Casey Dreier has analysis of NASA's 2015 budget plans, and Bill Nye sees the inherent optimism of science in the verification of another 715 exoplanets.Learn more about your ad choices. Visit megaphone.fm/adchoicesSee omnystudio.com/listener for privacy information.See omnystudio.com/listener for privacy information.

How to X-ray a Supernova, this week on Planetary Radio. Welcome to the travel show that takes you to the final frontier. I'm Matt Kaplan of the Planetary Society. NuSTAR is the first high-energy X-ray telescope in space. Principal investigator Fiona Harrison will share the secrets it is revealing about black holes and exploding stars. Bill Nye has a few enthusiastic words for us about the confirmation of 715 more exoplanets by Kepler scientists. And Bruce Betts finally gets his latest goody from the JPL gift shop, but only if he tells us what's up and offers a new space trivia contest.

Emily Lakdawalla is off this week. Taking her spot is the Planetary Society's Director of Advocacy, Casey Dreyer. We talked on the morning of March 4th when big news had just come from NASA HQ in Washington. Casey, thanks for jumping into this as we speak just really a few minutes after the big press briefing done by Charles Bolden and NASA's CFO. Yes, we have the president's budget request, so kind of kicking off the budget cycle for 2015. Within that budget request, NASA's top line drops down to $17.46 billion. That represents a cut of about $250 million from the president's last request and about $200 million from what Congress actually gave it last year. And we're talking about fiscal year 2015 here, which

federal year starts October 1. But there is this additional almost $900 million, which is just sort of what icing on the cake. Yeah, the Opportunity Growth and Security Fund, I believe is what it's called. And this all has to do with kind of political issues between Congress's spending caps on discretionary spending in the United States and what the White House would like to spend. There's a difference. So the president submitted a budget that fit the congressional limits. But in addition, they put out a $56 billion plan that said, this is how we would spend more money if we could close some tax loopholes and add some additional taxes on some obscure things. And within that, NASA would get $900 million more. It's very unclear where this goes.

It seems unlikely to me, and I think to most people, that Congress will act on any of these tax reforms anytime soon. Now, this is a very complex budget with a lot to talk about, and all we can do here is tease people a little bit and encourage them to look at your blog at planetary.org, where, of course, you follow this on an ongoing basis. But we have another longer conversation that people may want to check out. We're pushing it out online, but it is also going to be at planetary.org.

Probably we'll link to it from the show page, this week's show page, planetary.org slash radio. Just say a word or two about where this leaves planetary science. So planetary science, the administration takes a turn and starts adding some money back. It's still below for the third year in a row now. It still represents a cut from what Congress has been giving planetary science. But it's not as bad of a cut. So that in itself, I think, is progress. And we think now that NASA admits and acknowledges that planetary science has been underfunded,

we can use this and continue increasing the commitment to explore the solar system. The other big news, and which we'll see a lot more about, is that NASA also acknowledges the importance of going to Europa. They put in a small placeholder amount of money to start looking at a Europa mission. Now, this is a long way from going to Europa or even cutting metal or even knowing what they want to send. It's not the Clipper mission, from what we can tell. This is a different type of mission concept. We don't have a lot of details, but fundamentally, NASA is admitting and, again, acknowledging that Europa is important and deserves its own mission. So we're very happy with that. There is so much more for us to talk about, and you can hear us talk about it, as I said, at the link to a longer conversation with Casey Dreyer, the Planetary

Society's Director of Advocacy, at planetary.org slash radio. Bill, you've got to love that a spacecraft in one fell swoop, or one wonderful paper by a bunch of great scientists, and we talked to one of the leads last week, has just about doubled our knowledge of known planets in the galaxy. It is astonishing. You know, when I was in school with Carl Sagan and Frank Drake, also as at Cornell, the Drake equation, famous way of estimating the number of societies that

might be trying to get in touch with us, they would conservatively say, well, perhaps one out of every 100 stars has a planet orbiting it. Well, now it's apparent that every star has got planets orbiting it, and it just boggles the mind because it just increases the likelihood of Earth-like planets where there's liquid water, which we still presume is the best way to get a solvent for the chemical processes of life, fantastically increases the possibilities of that. As I always say, Matt, if we were to discover life on another world,

it would utterly change this one. And as we heard from Jason Rowe, our guest last week, who's part of this Kepler team, it's really just a matter of time before they confirm. I called it Earth 2. He said anybody who looks at this data, because the data's out there, there's some pretty tantalizing stuff there just waiting to be confirmed, and it probably will be. I mean, we're playing the hand we're dealt in the space-time continuum.

Matt, just think, perhaps a century from now, or your children, your grandchildren. Matt has two lovely daughters. Thank you. Your grandchildren, well, yeah, we could put a joke there, but I'll let it go. Your grandchildren could take it for granted that there's another civilization on another Earth-like planet. The future is amazing. It's amazing. This is what I always say about space exploration.

You know, Matt, this is what I told the president of the United States. The thing about space exploration is it's optimistic. Looking for these planets is inherently optimistic. You believe that there's something out there and you design an instrument, a spacecraft, to go looking

and you find it. It's nice to be in at least one little end of this human endeavor. And I'm thrilled to be talking to you about it, Bill. Thanks again. Thank you, Matt.

He's the CEO of the Planetary Society, Bill Nye, the science guy. Quick, name three space telescopes. I'm willing to bet NuSTAR didn't come to mind. That's the Nuclear Spectroscopic Telescope Array. Its boss is Fiona Harrison, the Benjamin M. Rosen Professor of Physics and Astronomy at Caltech. After just a year and a half up there, NuSTAR has already delivered results that have shaken up theories about some of the most exciting and mysterious phenomena in this universe.

The latest findings will help scientists understand how supernovae explode so cataclysmically. I recently visited with Fiona to hear more about that and other work by NuSTAR. Fiona, it's great to see you again, and congratulations on having this paper published, you and a lot of co-authors, in the journal Nature. Yeah, thanks. We were really excited about the result. Is this the first palpable public result of what New Star has in store for us? Well, actually, we had another result last year about measuring how fast a black hole was spinning. And that was a really exciting result. But this,

the special thing about this result is we really, we built NuSTAR to do this, to make the first ever map of the remnant of an exploded star in radioactivity. And we're going to come back to that and explain why NuSTAR was able to do this. And no other instrument has been able to pick up this data. But first, now you and I have spoken before because we did an event for another program that I do. But this audience, NuSTAR may sadly be new to many of them. Would you talk about what this pretty amazing X-ray telescope, why it is so important in this collection of telescopes, of instruments that we now have in space.

Yeah, so NuSTAR is the very first telescope that can actually focus high-energy X-rays. We've had telescopes in the past, big ones like you may have heard of the Chandra X-ray Observatory or XMM-Newton, that have been able to focus low-energy X-rays. But for the first time, getting to higher energies and being 100 times more sensitive and making images that are 100 times crisper than what's been possible before, we're able to study some of the hottest, densest, most energetic regions in the universe.

And the other interesting thing about NuSTAR is, you know, it's a first. It's hundreds of times more sensitive. But it's also NASA's smallest scale astrophysics mission. It's called a small explorer. And so this is the smallest standalone platform NASA does. This is the smallest standalone platform NASA does. And we were able to do this by developing new kinds of mirrors, new kinds of detectors, basically flying new technology. And this also partly explains why NuSTAR looks as interesting as it does. You have this beautiful model in your office here at Caltech behind us.

And it has basically two pieces with this huge boom between them. And that was expanded in space? Yeah, exactly. So the length, in reality, is about the length of a school bus. So 10 meters or 33 feet. Being a small mission, we had to launch on a small rocket. In fact, a rocket that fits underneath the belly of an L-1011 aircraft, in fact. So after launch, about nine days, we expanded this large mast out. It sort of looks like Tinker Toys. Yeah, it does. But it worked really well. And we were able to get the long separation we need

between the mirrors and the detectors to make this kind of telescope work. That must have been a scary moment, waiting to see if that would actually do what it was supposed to do in space. Oh, yeah, you know, so the Mars guys go on about their seven minutes of terror. This was 24 minutes of terror. As we watched it piece by piece unfold, you know, of terror. As we watched it piece by piece unfold, you know, 57 structural elements had to lock in place. But it all worked perfectly, just as we had planned. I knew what had gone into developing it and testing it. So I was nervous. But you know, the everything went right. Why is that length necessary? Is that because of the nature of the spectrum that it's looking at? Yeah, it's because of the way that you image X-rays, and in particular high-energy X-rays.

You can't make a mirror like you do for optical light. You can only reflect X-rays at very glancing angles. And because you're only deflecting them a little bit, it means that you have to have a long separation, basically, between your mirror and the digital film that captures the image. What do X-rays tell us about the universe that we can't get from visible light and the other parts of the spectrum? Actually, a lot of things. X-rays are emitted from some of the hottest regions in the universe. Black holes? Yes, the regions near black holes and galaxy clusters,

places where you have temperatures of 10 to 100 millions of degrees. Those radiate very strongly, emit a lot of X-rays. And in particular, the regions near black holes are really fascinating. You know, once you get really close to the black hole, you get particles that are accelerated close to the speed of light, and matter that's falling onto the black hole emits light and gets boosted up into the X-ray band. And so we're actually seeing the region right near the black hole.

I feel bad because I forgot. I had also seen that announcement of your results regarding the spin rate of a black hole. Why was it so difficult to determine that in the past? Let me back up a little bit and explain that black holes don't live in isolation. They live in isolation. They live in galaxies with lots of dust and gas. And that dust and gas falls onto the black hole. And when it gets close, it organizes itself into what's called an accretion disk, a disk-like shape.

Sort of think of a pancake. X-rays can reflect off of this disk, and by breaking them up into constituent colors, we can actually understand the structure of the disk, and in particular, how close it comes to the black hole. There's been evidence from low-energy x-rays that the disk was coming quite close to the black hole, and this can only happen if the black hole is spinning. General relativity tells us that, that if you want to have something orbiting stably, it can come closer if the black hole is spinning. Just by using low energy colors of x-rays, it was very difficult to tell that this was a unique interpretation of the measurements. There were other theories about what could be causing the particular pattern of colors. And by extending to higher energies, we were able to basically

unambiguously show that the black hole had to be spinning fast. You know, it's funny because reporters ask me, well, how fast is fast? You know, how many miles per hour. And that's the fascinating thing about black holes is you can't answer that question. Because black holes are points in space. You can't draw, you know, an X on the black hole somewhere and watch it, you know, how fast it's going around. What I usually like to tell people is that spinning black holes have energy that you can tap. And this particular 2 million solar mass black hole that we looked at, if you just grabbed it and stopped it, you would get out enough energy to blow up the entire galaxy that it lives in. So it's really a phenomenon. And when you say 2 million solar mass, you're talking probably one of these supermassive black

holes that tend to live in the center of places like the Milky Way? Yes, exactly. So this particular black hole is in a galaxy called NGC 1365. That's its telephone number. So that is, yes, one of these supermassive black holes. Fiona Harrison, principal investigator for the NuSTAR high-energy X-ray space telescope. I'll be back with her in a minute. This is Planetary Radio. Hey, hey, Bill Nye here, CEO of the Planetary Society, speaking to you from PlanetFest 2012, the celebration of the Mars Science Laboratory rover Curiosity landing on the surface of Mars.

This is taking us our next steps in following the water and the search for life, to understand those two deep questions. Where did we come from? And are we alone? This is the most exciting thing that people do. And together, we can advocate for planetary science and dare I say it, change the worlds.

Your name carried to an asteroid. How cool is that? change the worlds. You can submit your name and then print your beautiful certificate. That's planetary.org slash Bennu. Planetary Society members, your name is already on the list. The Planetary Society, we're your place in space. Welcome back to Planetary Radio. I'm Matt Kaplan. Every bit of the electromagnetic spectrum has the potential to reveal more of our dynamic universe. NuSTAR is the space telescope that looks at photons close to the top end of that mostly invisible rainbow, very high energy X-rays. Principal investigator Fiona Harrison of Caltech is telling us what this powerful instrument has already taught us. Let's move to an equally fascinating phenomenon, and those are supernovae, which is what you addressed in this

paper. What you learned is, I guess, helping us to understand how supernovas explode. Yeah, exactly. So the measurement that we were able to make was in a famous supernova, the light reached us about 350 years ago. And this supernova is called Cassiopeia A, or Cass A for short. And it's one of the best studied supernova remnants across, you know, an optical and X-ray. But by going to high energy X-rays, we were able to do something really unique. And that was make a map of this remnant in radioactive material. Now, in low-energy x-rays, you can make a map of this remnant in basically the hot shrapnel that was blown out after the explosion. And you're really only

seeing things that are hot. When you're able to see radioactivity, which is produced when you have elements that are unstable and decay. So, for example, the element we were looking at is titanium, like in your hip replacement, decaying into calcium. That we can see whether the material is hot or cold, and it's also an element that's produced very near the dividing line between what falls onto the compact remnant and what gets blown out into space. You know, when a massive star burns all its fuel, massive star means eight times the mass of our sun or more, it collapses, and the center of the star collapses into what we call a neutron star or could even form a black hole.

The outer layers of the star sort of fall onto that and then get ejected outwards. You can see the remnants, sort of the shrapnel glowing for, you know, hundreds to thousands of years afterwards. These beautiful images that most of us have seen, I think. Yeah, very spectacular. Very spectacular in the low-energy X-ray, too, because you can see different elements like iron and calcium and magnesium, all the elements that are made in stars.

Yeah, yeah, yeah, star stuff. Star stuff, yeah. Star stuff. Star stuff, right. But the big question is, has been, you know, how do you get something that is imploding to turn around and explode, right? You know, the thing is collapsing and it's got to turn around and sort of, you know, it bounces off this core and you have a shock that expands out and blows a star apart. And this has been really hard to understand theoretically because most models, you know, you have stars are spherical. But spherical models fail to be able to blow up stars. People have suspected, and there's observational evidence, that somehow you go from something that's spherical to something that's distorted in some way to get the star to blow up. And different models suggest different things. Some models suggest the star gets really distorted, perhaps even so that it explodes out in jets, you know, something that would look really non-spherical. Other models have suggested that the core of the star literally sloshes around

as it's exploding, and that sloshing helps the star explode. I was thinking of like, you know, water in a kiddie pool or something sloshing around when I read the press release. Yeah, or, you know, water boiling or, you know, sloshing around. And these are theories that run on big computers. And you want to know, you know, we'd like some evidence for what's going on observationally. Is it really like a jet or is it like the sloshing? By being able to make this image in the radioactivity, which is produced, what happens is it's produced right at the dividing line between what falls onto that neutron star I was talking about and what gets ejected out.

So it really imprints what the explosion looked like. So you can think of it as a picture of the heart or the core of the explosion, right? And then after, you know, for the 350 years afterwards, it's just kind of coasting out, expanding, but it's not really changing its shape. So we could take a picture then, the core of this explosion, and it looks very, very much like the models where you have the star sloshing around before it explodes, and nothing like the jet that people had proposed previously. So you got some model builders who are very, very happy with your results and a few who

have said, okay, it looks like we were wrong. Right. Well, there are different kinds of explosions where there may in fact be jets. So they can't be too disappointed. But in this particular case, and I think this is evidence that in these what we call core collapse supernovae, so the collapse of a massive star, that this sloshing model is important. And it was exciting because after our result was released, we did get a number of theorists sending us their papers saying, see, see, I predicted this. So that was great. And it's science.

And, you know, science is a human activity. They have a right to be proud. But there's nothing like having the data to back up your theory. That's right. What is this going to mean for our understanding of supernovae and the importance that they play in the universe. I mean, you already said much of what we are made of came out of a supernova some billions of years ago. Right.

Yeah, that's why supernovae are so important to understand, because in the early universe, it was just hydrogen and helium and a little bit of lithium, but that's it. Everything else, all the calcium in our bones and teeth, the gold in your wedding ring, that was all forged in stars since the Big Bang. It's forged in stars and these supernova explosions. And it's also the supernova explosions that are important in distributing the material throughout a galaxy. So it can form disks and out of that planets and out of that life. So these are really very central to why we exist.

And what NuSTAR is doing is helping us understand this process that forges the elements and distributes them. Black holes, supernova. What's ahead for NuSTAR? Well, so we're very excited that a different kind of supernova called a supernova 1A. You may have heard of these because these are what are called the standard candles that have been used to find evidence for dark energy in the universe. Nobel Prize was one for that recently. They are different. They aren't the collapse of a massive star. They are the detonation of what's called a white dwarf

star. And one went off really close in a galaxy called M82. And this is sort of one in every century sort of event would we expect something, one of these to go off this close. And so NuSTAR is off looking at that. We don't know the results yet, but we should be able to, if not make a measurement, put strong constraints on the explosion models for those. And that'll be quite interesting because we don't really know if it's a single white dwarf star that's exploded or maybe there's two white dwarfs in a binary that, you know, merge and explode. You know, it's really not understood. How long is NuSTAR expected to keep sending

great data back home? We launched in the summer of 2012. We have a two-year prime mission. And we just finished writing a proposal to NASA to extend the mission for two more years. NuSTAR doesn't have any what are called consumables. There's no fuel. No cryogenic stuff. No cryogenic stuff. So it's really just how long things last and how long we keep doing great science.

And I'm optimistic that that'll be for quite some time. Best of luck with that. The other thing that I have to say is coming out of this, and I hope we'll be able to use at least one of these images on the page where this show could be found at planetary.org slash radio are really beautiful pictures. Now I realize that's false color, but my goodness, they're, they're just gorgeous. Yeah, it's amazing. It's sort of the truth is stranger than fiction thing that you just look and think, boy, something that weird up in the sky. The images are great.

The data is great. And, you know, we've got students and postdocs and young people all excited about, you know, what we're going to look at next. So that's very rewarding. You are in this very select, this very elite group of principal investigators with your own telescope in space. Does it feel like a kind of a club, a fraternity or sorority? Yeah, well, we have a big science team. But there is nothing like the feeling of going down the hall and saying, well, I think we should look at this next week. the hall and saying, well, I think we should look at this next week.

Or something exciting goes bump in the night. And it's up to basically me to say, okay, turn the telescope and let's look, of course, with lots of advice from my team. But, you know, so it does feel like a club. But also one thing that I really want to do and that we've proposed to do in the extended mission is to open it up so anyone can write a proposal and use NewSTAR. You could. You just have to win. But literally anyone in the world can say, I want to use NewSTAR to do this. And then that's a good idea.

It gets accepted and gets done. So I'm looking forward to that next stage because it'll be really fun to see what other people dream up. Let us know when you get there. We'll maybe help get the word out that folks around the world, I mean, who knows? I don't think you're going to get anything useful or worthwhile from me. there with something that would just be ideal for an instrument like NuSTAR with a source of high-energy x-rays that maybe nobody in these halls would have thought of. Yeah, well, you know, I just had somebody email me the other day suggesting that we look at Jupiter, so there you go. Maybe there is something in it. Congratulations once again on the paper, and I sure hope that that

extended mission happens and NuSTAR continues to reveal these high energy secrets about our, maybe not just the whole universe, but maybe even closer to home in our solar system. Thank you. Fiona Harrison is the principal investigator for NuSTAR. That's the Nuclear Spectroscopic Telescope Array, which is right up there now, looking at yet another supernova. She's also the Benjamin M. Rosen Professor of Physics and Astronomy at the California Institute of Technology, Caltech. We're going to talk to another Caltech alum in a moment. That's Bruce Betts, the director of projects for the Planetary Society, because this is What's Up. And I'm very happy to be sitting across the table from you

because I can give you your gift, your latest present from JPL soon. Not yet. You have to earn it. Tell us what's up. cool things matt things that are deserving of a present i'll be the judge of things like jupiter in the evening sky in the south looking super bright and then a couple hours later mars comes up in the east looking reddish and then a couple hours later saturn comes up in the east looking yellowish and then many hours later venus comes up look low in the east in the pre-dawn for super bright venus and you might be able to check out mercury below it closer to the horizon for the next week

or two we move on to this week in space history it was 1781 you remember what happened then don't you 17, no. William Herschel discovered Uranus. Now, see, I should have remembered that because I read a book that was largely about William Herschel. Quite a guy. Also very impressive, his sister. You have a crush on William Herschel's sister? She's very crushable.

I'm sure at this point she is. She was a pioneer. She did a great job. Look it up. Okay. A little more recently, 2006, Mars Reconnaissance Orbiter arrived at Mars and, of course, still doing great, sending back fabulous data. Random space fact. That was not my head that you heard being pounded right there. It was a little Tarzan action from Bruce.

Okay. Kepler, the exoplanet-discovering spacecraft, able to sense a drop in brightness of only one one-hundredth of a percent when looking for a planet moving in front of its parent star. But wait. That is equivalent, according to their website, as well as the Earth and Space Calendar, to detecting the drop in brightness of a car's headlight when a fruit fly moves in front of it. Yes, impressive instruments they've got there.

Speaking of impressive, let's go on to the trivia contest. I asked you, what is the approximate range of elevations on Venus? So, in other words, on Earth it's about 20 kilometers from the top of Everest to the bottom of an ocean trench. How'd we do for Venus? You weren't talking about Botticelli's Venus, were you? I suppose I have to give it to people if they came up with that. We did get those rough dimensions just eyeballed, actually,

by Russ Black in Shoreline, Washington, but I won't repeat them here. That's probably good. I think you had something else in mind. I had the planet. Oddly enough, on planetary radio, I had the planet in mind. It was Doug Stern who won this time out. This was a challenge for people. The number of entries kind of went down, and people struggled.

We had more wrong answers than usual. Is it roughly a 13-kilometer range? It is indeed approximately a 13-kilometer range. But really, most of the planet is just flat. It is very flat, but it's got these big mountainous areas. But yeah, a lot of flatlands, a lot of prairie, minus the buffalo and the nice temperatures and the wheat. Well, Doug Stern, we're going to send you that Beyond Earth letterpress poster from Chop Shop at chopshopstore.com.

That's where you can check it out. It's a wonderful poster. It's so wonderful that we're going to give away one more. But I should tell you first about one other response that I got from Kurt Lewis, who said that clearly Venusians who are accustomed to such a flat terrain would not be happy with the hilliness of earth. That would be in addition to the fact, he adds, that they would explode. Oh, look at these terrible... Yeah, hard to sell to the Venusian Travel Agency, I suppose. Pack wisely.

Exactly. Now you can go on. All right. Next time, trivia contest. Here it is. What was the first time astronauts flew in a spacecraft not designed to re-enter the Earth's atmosphere. Kind of a risky proposition, but flying separately in a spacecraft that was not designed to safely re-enter the Earth's atmosphere.

I should be clear. Obviously, any spacecraft can re-enter the Earth's atmosphere. This one was not designed to survive it. Good clarification. That's fascinating. Go to planetary.org slash radio contest to get us your entry. By when?

At 8 a.m. That's the new time on Tuesdays, the 18th at 8 a.m. Pacific time. You just keep shifting times to keep people on their toes. I guess that must be what it sounds like. But really, there is some thought, rational thought behind this. Okay, you ready? I'm ready. All really, there is some thought, rational thought behind this.

Okay, you ready? I'm ready. All right, here we go. You can open it up. Here, there's the bag, a little JPL bag. Indeed. They are glow-in-the-dark. Glow-in-the-dark shaped rubber bands.

Yeah, they have little space shapes. Planets and rockets and stuff like that there. That's fantastic. I'm glad you like it. This is what the plastic wrapper sounds like. If it was open, you could shoot me with a rubber band. Oh, it is open. I spoke too soon. Say goodnight, Bruce. Go out there, look up at the night sky

and think about fur while I take this astronaut, deform him, and shoot him at Matt. Go ahead. And good night. Ow! Ow! He's Bruce Fetz, the Director of Projects for the Planetary Society, and he joins us every week here for What's Up. Oh, get up! Planetary Radio is produced by the Planetary Society in Pasadena, California, and is made possible by the elastic members of the Society. Clear skies.