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← The Mars MAVEN Mission and "Dreams of Other Worlds" author Chris Impey - SA Hangout #7

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  1. JM: Hi everybody! This is Joanne Manaster,
    a blogger with Scientific American
  2. and I'd like you to welcome to this
    very special Scientific American chat
  3. that we are airing on the heels
  4. of NASA's press conference yesterday
  5. about NASA's MAVEN space orbiter
    that is expected to launch
  6. mid-November to head to Mars
  7. to look at the non-existent
    atmosphere of Mars
  8. and wonder, where did it go?
  9. So I'm joined today by two special guests
  10. who can enlighten us about
  11. both what's going on with the orbiter
  12. and about unmanned or robotic
    space exploration in general.
  13. So first, I'd like to introduce you
    to a NASA space scientist,
  14. one of the MAVEN scientists,
  15. Nick Schneider, from the
    University of Colorado in Boulder.
  16. He's with the Laboratory for
    Atmospheric and Space Physics.
  17. That's a mouthful.
  18. And he's one of the members
    of the Science Team.
  19. I'm actually going to pull up…
  20. He's an Associates Professor
  21. in the Department of Astrophysical
    and Planetary Sciences
  22. at the University of Colorado.
  23. He received his PhD in Planetary Science
    from the University of Arizona.
  24. His research interests include
  25. planetary atmospheres
    and planetary astronomy
  26. with one focus on the odd case
    of Jupiter's moon, Io.
  27. He is also the lead on the
    Imaging Ultraviolet Spectrograph
  28. on the upcoming MAVEN mission to Mars.
  29. He enjoys teaching at all levels
  30. and is active in efforts to improve
    undergraduate astronomy education.
  31. I'd go for that.
  32. Off the job, he enjoys
    exploring the outdoors
  33. with his family
    and figuring out how things work.
  34. What I have here?
  35. I'd like to show up something you've done.
  36. You are one of the authors on this book
  37. which I hear is in 7th edition.
  38. NS: That's right.
  39. JM: The Cosmic Perspective
  40. This is a beginning astronomy textbook.
  41. NS: Exactly.
  42. JM: Welcome Nick.
  43. I'm going to introduce Chris right now.
  44. Chris Impey is a
    university distinguished Professor
  45. at the University of Arizona.
  46. So you guys have a connection.
  47. And he's Deputy Head
    of the Astronomy Department.
  48. His research interests include
  49. observational cosmology,
    quasars, and distant galaxies.
  50. He has written 160 research papers
    and two astronomy textbooks
  51. but you say those are online, right?
  52. CI: Yeah, the one's repurposed.
  53. It's called Teach Astronomy
    so it's up there and free.
  54. JM: Oh, great. He has won
    11 teaching awards
  55. has served as a National Science
    Foundation distinguished teaching scholar
  56. a Phi Beta Kappa visiting scholar
  57. and the Carnegie Council's
    Arizona Professor of the Year.
  58. He is former Vice President of
    the American Astronomical Society
  59. and Fellow of the AAAS.
  60. He has four popular books
    actually now five:
  61. The Living Cosmos,
    How It Ends, Talking About Life,
  62. and the one that we are referencing today
  63. called Dreams of Other Worlds
  64. which is the Amazing Story of
    Unmanned Space Exploration
    .
  65. So welcome, Chris.
  66. CI: Thank you.
  67. JM: It's great to have you both here.
  68. Before we go forward
  69. in News of Space today,
  70. Chris Hatfield, Col. Chris Hatfield
    from the Canadian Space Agency
  71. who was on the ISS and returned recently.
  72. As we know he made
    a big splash on social media
  73. with his images, and singing,
  74. and his videos explaining his music.
  75. He has published a book
    It is out today.
  76. So if you haven't gotten
    you haven't heard of it, it's called
  77. An Astronaut's Guide to Life on Earth:
    What Going to Space
  78. Taught Me About Ingenuity, Determination,
    and Being Prepared for Anything
  79. And we at Scientific American
  80. will have him as a guest
    on November 14th at noon.
  81. So mark that on your calendars
    and join us if you can for that.
  82. So, let's talk a little bit about MAVEN
  83. before we talk about un-manned
    space exploration in general
  84. or robotic space exploration in general.
  85. There's a lot of interest,
    so why don't we do some of the details?
  86. When is this expected to launch?
  87. NS: MAVEN is slated to launch
    in the afternoon of November 18th.
  88. It's a short period every afternoon
  89. for a couple of weeks
  90. when all the planets are aligned,
  91. because we have to have the Earth
    in the right position relative to Mars
  92. and the right rotation of the Earth
  93. so that the spacecraft will actually
    get to Mars on time.
  94. If you ever wanted to know somebody
  95. whose life was controlled
    by the positions of the planets
  96. well, that's anybody trying to launch
    a spacecraft to another planet.
  97. JM: But not the rest of us.
  98. So what's in paper is not relevant at all.
  99. But actually there are several days
  100. so you have a window
    of several days during this time.
  101. NS: That's right, it's a couple of weeks
    and the main thing that happens
  102. if the planets go out of alignment
    it just takes a little bit extra fuel.
  103. And fuel is precious,
    it's our ability to maneuver
  104. when we get to Mars.
  105. So we really want to launch
    at that sweet spot
  106. early in the launch window.
  107. JM: That's fantastic.
  108. I'm excited because I'm going down
    for the launch, myself.
  109. The only other launch I've seen
  110. is the last space shuttle launch.
  111. I'm glad I got to see that one.
  112. So, I'm looking forward
    to watching an Atlis-5 go off.
  113. NS: Me too.
  114. JM: I'm really quite excited about this.
  115. So, as far as…
  116. We're wondering, for those of who did
    not catch the press conference yesterday.
  117. What is MAVEN going to do?
  118. NS: Sure, I'm happy to explain that.
  119. I'm pretty sure that
    the members of the hangout
  120. are going to be pretty familiar
  121. with the basics on Mars.
  122. A hundred years ago or more
  123. anybody who looked through
    the telescope on Mars
  124. really wondered what was going on
    with the change of the seasons.
  125. There was actually a suspicion
    that there was life on Mars,
  126. water on Mars,
  127. but by the time
    the first NASA probes got to Mars
  128. what they discovered instead
  129. is that the atmosphere now
    is next to nothing.
  130. There's no flowing water or evidence
  131. of abundant water on the surface
  132. and instead it's this really cold
  133. really dry planet.
  134. And yet, you look at those images
  135. and what you see from the spacecraft
  136. are dried up river beds
  137. river deltas filing up craters.
  138. There must have been
    a warmer wetter environment
  139. billions of years ago.
  140. And the only way that's possible
  141. is for there to have been
    a huge greenhouse effect
  142. with lots more atmosphere.
  143. Everybody's best guess
  144. is that Mars has lost
    80, 90, 99% of the atmosphere
  145. over billions of years.
  146. We used to think that
    the atmosphere on Mars
  147. might have combined with the surface.
  148. That's actually where limestone
    comes from on the Earth.
  149. It's carbon-dioxide being
    sucked into the surface.
  150. But the missions sent to Mars so far
  151. can't find enough evidence
  152. that the atmosphere
    re-combined with the surface.
  153. So we're left with the other possibility
  154. that the atmosphere escaped away to space.
  155. And so that's what MAVEN
    is going to go check.
  156. Is it possible
  157. that through the host of processes
  158. we understand that the escape rate
    of the atmosphere to space
  159. is large enough to explain
  160. where almost all the early
    Mars atmosphere went?
  161. And I can get into more detail
  162. about how we make
    those measurements, if you want,
  163. but I just wanted you
    to get the basic idea
  164. about what MAVEN's about,
  165. JM: That's interesting.
  166. So part of my interest in this
  167. is I was invited to come
    to a New Media workshop
  168. out there at the University of Colorado
  169. and to listen to you scientists talk about
  170. what MAVEN was all about.
  171. So I'm happy to follow up
    with this hangout
  172. for the Scientific American audience.
  173. One thing that was interesting was
  174. Why didn't we send a probe to Venus?
  175. We've sent probes elsewhere
    to look at the atmosphere.
  176. But why not Venus?
  177. I mean that's so obvious
    it's so close, but…
  178. I'll actually ask Chris
  179. to weigh in on this because
    you've just written a book
  180. about almost every single
    unmanned exploration craft
  181. that's been sent out.
  182. CI: I think that the trouble with
    planetary science now
  183. is there's so many good ideas to pursue,
  184. and so few new starts possible
    in the budget.
  185. You can't do everything.
  186. I was hanging out at JPL
  187. lecturing to engineers there
  188. and one of them was the lead
    on a Venus mission,
  189. a Venus lander,
  190. which got deselected at the last stage.
  191. When it got down to the final four
    it wasn't picked.
  192. And it was really challenging
  193. because, you know, Venus
    is a pretty nasty place
  194. and they had a mission
    that was going to land there
  195. take data for ten days
  196. before it got baked out and died
  197. and learn an enormous amount about Venus.
  198. So, you know, there are missions
  199. sitting there on the shelf
  200. from NASA people
    and people who work with NASA
  201. to do almost everything you could imagine
  202. whether it's Hydrobot
  203. melting through the European ice pack
    and looking for life
  204. or going back to Titan with dirigibles
  205. and sampling all the lakes
  206. or the more advanced Mars concepts
  207. that would actually look for life
  208. by drilling down to what we think
    might be aquifers underneath.
  209. There are all these concepts out there
  210. and not enough coin to do most of them.
  211. JM: Yeah,
  212. with the number of things we've sent out
  213. and we've learned a lot,
    it just seems infinite
  214. what else we could possibly learn
  215. if we could send every dream
  216. of explorers out there.
  217. Actually before we get back to
    the Mars atmosphere and MAVEN
  218. I was interested,
  219. when I first mentioned to my editor,
  220. I want to talk about this book
    and the MAVEN thing.
  221. Your subtitle is The Amazing Story of
    Unmanned Space Exploration
  222. and I was immediately countered with
  223. "Oh, that's not the correct term
  224. "the politically correct term
  225. "to use the word 'unmanned' ".
  226. And I inquired of you about that.
  227. So do you want to explain why you chose
    "unmanned" versus "robotic"
  228. despite the fact "unmanned"
    might upset people?
  229. CI: To be honest, that was
    a publisher decision actually
  230. They published a book
    and they get the deciding vote on that.
  231. "Robotic" would have been
    a better choice, I agree.
  232. And, we've had to take
    the various languages…
  233. Look at the evolution of the Star Trek
    the famous Star Trek line,
  234. "where no man has gone before" to
    "where no one has gone before"
  235. So there's been
    suitable and appropriate evolution
  236. of some of these iconic phrases
  237. JM: So, would both of you agree that
    "robotic" is probably
  238. just a better term, or a perfect term
  239. or is there an even better term?
    'Cause we've sent out telescopes…?
  240. And when I think of "robotic"
  241. I think of lots of moving arms
  242. and things that are grabbing things
    to bring back to analyze
  243. and less so just
    analytical equipment or optics.
  244. But, I guess, my expansion of "robotics"
    might need to expand.
  245. NS: I use "robotic exploration".
  246. CI: They do feel quite different.
  247. Orbiting telescopes
    or telescopes at the LaGrange Point
  248. they're just the technology
    we use on Earth to observe
  249. transplanted into space.
  250. And we remote observe on the Earth
  251. I don't have to go to
    Chili or Hawaii anymore
  252. because I can remote observe
    from my office.
  253. But I think "robotic" is appropriate
  254. for the planetary missions
  255. because they're literally
    like sense extenders.
  256. They're our eyes and our ears
  257. on another world, and we often
    operate them that way.
  258. JM: I'll have Chris give sort of
  259. a history of robotic exploration
    on Mars for us
  260. and then we'll go back and talk a
    little bit more about the MAVEN mission.
  261. So, think back to your book,
  262. what you've talked about
    the different explorers
  263. that have goneto Mars
    and what they've accomplished.
  264. Maybe their drawbacks
  265. and how we're improving on that?
  266. CI: Right, why I was interested in that book
  267. is that I think that some people
  268. just underestimate how fantastic
    these technologies really are.
  269. Just setting Mars aside for a minute,
  270. the Huygens probe to soft-land on a world
  271. nearly a billion miles away
  272. and then inspect it
    and find that it has
  273. this bizarre Earth-like lakes,
  274. and weather and cryovolcanism,
    and all this cool stuff.
  275. That's an amazing achievement
  276. and to go back to the beginning
  277. the Viking missions, long forgotten now
  278. most Americans were not alive
    when those missions were designed.
  279. They were 1960s technology
  280. Think of computers then,
    think of electronics then.
  281. And those two landers and two orbiters
  282. did amazing things.
  283. They did life-detection experiments
  284. that have not been surpassed since
  285. and one of which at least
    led to an ambiguous result.
  286. So, the Vikings were amazing missions
  287. for that time, 40 years ago
  288. and we've just continued
    the progression with rovers.
  289. Then NASA having gone for the
    bouncing bag landing mechanism
  290. which is kind of safe, very forgiving
  291. upped the degree of difficulty hugely
  292. with Curiosity and the Skycrane.
  293. So again, amazing technologies
  294. really high risk
  295. and high reward
    and high payoff activities.
  296. These types of missions
    absolutely push our technology.
  297. Now a geologist would tell you
  298. there is no substitute
    for bringing back Mars rocks.
  299. On Earth you could examine them
    molecule by molecule.
  300. But what you can compress into
  301. something that you can launch
    and will survive the passage
  302. and the launch, and the entry into Mars
  303. is still pretty amazing technology.
  304. The instruments on Curiosity,
    for instance,
  305. I think we absolutely push the envelope
  306. of almost everything
    we can do in technology
  307. when we design these kind of missions.
  308. NS: Yeah, Chris, if I can jump in here
  309. and add onto this
    you talk about high technology
  310. high performance, high capability.
  311. But part of the message
    that sometimes gets lost
  312. is that this is also low cost.
  313. If you think about every image
  314. ever returned by Cassini spacecraft
  315. or every rock ever picked up
    by a Mars rover
  316. the sum total of all this
    robotic exploration
  317. is less than half of NASA's budget.
  318. It's a small fraction.
  319. Putting humans in space
  320. as dramatic and as forward moving as it is
  321. and as much as I love that, too
  322. that's more expensive.
  323. What we can do with robots
  324. being so much more affordable
  325. we can go everywhere
    and we can go there now.
  326. So, it was really the immediacy
    of robotic exploration
  327. and our pervasive presence in space
  328. that makes it such
    a compelling subject for me.
  329. CI: And, of course, that advantage
    will just continue to grow
  330. because the robotic missions
  331. will become more miniaturized.
  332. They will benefit from Moore's Law
  333. and humans are always going to be tricky
  334. and difficult to sustain in space.
  335. Space is not a natural place for humans.
  336. We're sort of shading into a huge debate
  337. that plays out in our various communities
  338. of man versus unmanned
    or human versus non-human or robotic
  339. and it doesn't have to be either or.
  340. You're going to be talking
    to Chris Hatfield
  341. and when the astronauts
    like him or John Grunsfeld
  342. who we've had here a number of times
    and who's a hero.
  343. He walks into the auditorium
    and he gets a standing ovation
  344. from 200 astronomers
    the guy who fixed Hubble three times.
  345. So, there's no substitute for that either.
  346. But it's expensive.
  347. The space shuttle real cost
  348. was half a billion dollars a launch
  349. and a couple of shuttle launches
  350. buys you a really cool planetary probe

  351. so that's a hard trade-off.
  352. JM: I actually really liked
    your recap of the Hubble
  353. the entire Hubble
    building, launching, and repair
  354. in your book.
  355. It's worth visiting the book just for that.
  356. But I did really like that retelling.
  357. What I wanted to say
  358. now that Chris has
    talked about the different
  359. probes that are there
    that we sent there.
  360. Of course, we know
    we just had a government shutdown
  361. and this probably had you guys
    at MAVEN sweating... a lot
  362. but you got a bit of a reprieve
  363. and they allowed you to continue the work.
  364. Do you want to explain why you guys
    were allowed to get that exemption?
  365. - Sure
    - But the NAH couldn't?
  366. NS: So, the MAVEN project did stand down
  367. for a couple of days
  368. under the government shutdown.
  369. We were all very anxious
    and frustrated by this.
  370. This mission is ready to go
  371. and it's got great science
  372. but under the terms of the shutdown
  373. that's not enough to get the exemption.
  374. And even the fact that missing this launch
    window that I talked about
  375. and waiting in cold storage
    for a couple of years
  376. for the next chance would cost
    a couple hundred million dollars
  377. even that was not enough.
  378. But, what really mattered is the fact that
  379. built into MAVEN is a relay capability
    for radio transmission
  380. with the rovers on the surface
  381. and so it's really these ongoing missions
  382. that we need to preserve
    the capability for communication.
  383. That was the primary justification
    for MAVEN getting
  384. exempted from the shutdown.
  385. There are a couple of satellites
    around Mars
  386. that are capable of performing
    that relay function
  387. but they're getting
    a little long in the tooth
  388. and we needed to make sure that MAVEN
    would get there in this launch window
  389. to be able to fulfill that role as needed.
  390. Now we hope those other missions survive
  391. but the last thing you want
  392. is Curiosity, on the surface
    making great discoveries
  393. and no capability for
    the high data rate back to Earth.
  394. So that was what got MAVEN back on track.
  395. And we are on track
    for the launch on November 18th.
  396. Did I say November 18th?
  397. JM: Yes.
  398. CI: I can't resist commenting that.
  399. We're talking about how high-tech
    space exploration is.
  400. One of the areas where it's really
    behind the curve is communication.
  401. Probably some of your viewers may know
  402. that Vincent Serf, who is the architect
    of the original internet
  403. is now working with NASA
    on an interplanetary internet,
  404. because there are real problems
  405. with operating the internet
    beyond the Earth
  406. because you have missions
    with hour-long transmission times
  407. and they have to look up IP addresses
  408. and they have to get hooked
  409. into the patchwork quilt
    that is the internet
  410. and the protocols that go with it.
  411. There's no way to do that right now.
  412. So, we actually have to design
    an entirely new architecture
  413. for interplanetary internet
  414. on which all of these
    space missions will depend.
  415. JM: That's really interesting.
  416. CI: It's been pioneered by the mission
    that's just gone to the moon, actually.
  417. JM: Bellary.
  418. CI: Bellary has been just pioneering
  419. some of the first transmission protocols
    under this new internet
  420. a protocol for planetary explor…
  421. JM: Is that built into the MAVEN, too then?
  422. NS: No, we don't have
    that advanced technology.
  423. JM: You have a picture
    of MAVEN behind you
  424. and you also have a model.
  425. Why don't you pull that forward
    and sort of explain
  426. what we've got going on
  427. so people have a…
  428. Because everyone's got this idea
  429. of what Curiosity looks like, right?
  430. Because there are just images all the time
  431. of the rovers displayed on the internet
    and everything.
  432. So, I thought we could get an idea
    of what an orbiter this type
  433. is going to look like and do.
  434. NS: Sure, and I'm glad you emphasized
    the word "orbiter".
  435. This spacecraft doesn't land
    on the surface.
  436. We just orbit the planet
    over and over again
  437. about every five hours, or so
  438. studying the different ways
  439. that the atmosphere
    can escape away to space
  440. and even what the atmosphere properties
  441. are high up in the atmosphere.
  442. But to give you a bit of a tour
  443. this is a 1/30th scale model.
  444. So the actual MAVEN spacecraft
  445. from tip to tip is about the size
    of a school bus.
  446. And everything that you see out here
  447. all this real estate, is the solar arrays.
  448. So we gather enough solar power
  449. to fuel all of our instruments
    all of our controlled electronics.
  450. Right here is where
    we keep the explosives.
  451. This is the fuel that we fire
  452. as we enter Mars' orbit.
  453. It has to slow us down
    all the excess energy
  454. that we arrive there with.
  455. And, so the actual
    rocket nozzles are down here.
  456. And this is our relay antenna
  457. by which we send
    our own data back to Earth
  458. and also any data from the rovers
  459. when they need us
    to perform that function.
  460. And when we talk about robotic exploration
  461. we might say that humans
    have five senses
  462. Well, I have to say that
    spacecraft can have dozens
  463. or you can choose from dozens
    of different kinds of senses
  464. when you're designing
    your robotic explorer.
  465. And Chris has already talked about
  466. how robots can be the eyes and ears
    and those analogies are really quite good.
  467. So, for example, you can see
    we've got these antennas here
  468. and we've got some
    devices out on the end here.
  469. These are like the ears of the spacecraft
  470. listening to the magnetic and electric fields
  471. as they change in the vicinity
    of the spacecraft.
  472. One of the things our spacecraft does
  473. is it actually flies
    through the atmosphere
  474. actually it flies this way.
  475. That's why the solar arrays
    are angled like that.
  476. As we fly through the atmosphere
  477. we have a handful of instruments
  478. that it's like smelling
    or tasting the atmosphere.
  479. Particle by particle they can see
    what the atmosphere is made out of
  480. and even how fast
    those particles are going
  481. and if they'll escape away.
  482. My baby is this instrument, right here.
  483. It's the Imaging Ultraviolet Spectrograph.
  484. It's the eyes of MAVEN.
  485. You might not know it
  486. but every atmosphere in the solar system
  487. is glowing like crazy in the ultraviolet.
  488. We have this instrument
    that can spread the spectrum apart
  489. and see how much carbon dioxide is,
  490. how much hydrogen, how much oxygen,
  491. all those different ingredients
  492. how they're distributed
    through the atmosphere
  493. and even, again,
    their chances of escaping.
  494. So this spacecraft is perfectly designed
  495. with every instrument onboard
    that's necessary
  496. to track all the different ways
  497. that the atoms and molecules
    of the Mars atmosphere
  498. can escape away to space.
  499. Did I leave anything out?
    Did you have any questions?
  500. JM: When you're saying it's going
    through the atmosphere
  501. were you saying that's towards the planet
    or away from the planet?
  502. Because there are some dips
  503. you are doing, like planned…
  504. NS: That's right.
  505. Let me get my other prop here.
  506. JM: Which will not be to scale?
  507. NS: I don't have enough hands
    to really do it right.
  508. But to keep things in perspective
  509. remember that a planet's atmosphere
  510. is really thin on the scale of the planet.
  511. Mars is considerably
    smaller than the Earth,
  512. larger than the moon
    intermediate-size planet
  513. but still the atmosphere
    is just about 100, 200 km down here.
  514. And our spacecraft is designed
  515. to swoop from high altitudes here, down
  516. and fly, skim through the upper layers
  517. where the air resistance
    is pretty significant
  518. and then come back up again.
  519. We're actually able to take
    images of the planet from up here
  520. and then we'll dip back down.
  521. And, every now and again
    we change our orbit,
  522. so that we go even deeper
    into the atmosphere.
  523. It's still far above where airplanes fly
    or anything like that
  524. in terms of density in Earth's atmosphere
  525. but it's a region of great interest
  526. for the upper layers of the atmosphere
  527. where gasses start to escape.
  528. So we call those deep dips.
  529. Nonetheless,
  530. it's pretty I won't say hair-raising
    I'll just say unnerving
  531. the sight that every orbit
    we dip down into the atmosphere
  532. that's just a little bit of friction
    and we come out again.
  533. It's why we need to have fuel
    so we can continue to tune the orbit
  534. and not dip down any deeper
    than we need to, scientifically.
  535. JM: So how long is this…
  536. How long is MAVEN's,
    your science project, supposed to last?
  537. And then I'll get to Chris
    about the longevity of things
  538. because things have lasted
    longer than we thought.
  539. So your project
    is slated to last how long?
  540. You'll be collecting data officially…?
  541. CI: The MAVEN primary mission
  542. is one Earth year in duration.
  543. We were hoping that we could
    slip in the fine print
  544. change one Earth year to one Mars year
  545. but it turns out they're tracking that.
  546. But one Earth year is enough for us
  547. to sample all the different
    conditions of the atmosphere
  548. especially how the atmosphere behaves
    when the sun kind of goes kablooey.
  549. I'm sure that the viewers
    are aware of solar activity
  550. and the way that the sun
    can spit out
  551. extra energetic photons,
    energetic particles.
  552. Those are the processes that can
    strip away the Mars atmosphere.
  553. And we really want to study how the
    atmosphere behaves under those conditions
  554. and we should see that
    in our one Earth year primary mission.
  555. JM: So there's an anticipated
    major solar activity, right?
  556. That this is of concern as you guys arrive
  557. if I remember correctly?
  558. NS: The sun is unpredictable.
  559. We don't know what the sun's going
    to do when we arrive,
  560. You might be thinking about the comet
  561. that gets to Mars
    around the same time that we do,
  562. JM:That must be what I'm thinking of
    which is different.
  563. NS: Always something going on
    in our solar system.
  564. JM: Now, you will not be doing
    any sort of readings on the comet
  565. unless it affects the atmosphere, right?
  566. NS: That's too soon to tell.
  567. We're putting all that on hold
    until we're safely launched.
  568. I just needed to correct
  569. something that I said a minute ago
    and that is to say
  570. we are arriving at Mars
  571. while the sun is
    in a statistically active period.
  572. So that part was correct.
  573. But whether or not there's going to be
  574. a good solar storm the day we turn on
  575. we wish, but we don't know.
  576. JM: We don't know that for sure,
    that's one of those things.
  577. I want to pop back to Chris
    because, first of all,
  578. this area writing this book
  579. about unmanned space exploration
    is not your original field of study.
  580. This is not what you prefer to do
    but you're very interested.
  581. You've been allowed a lot of insights
    by the people you know.
  582. NS: Yeah, he chose the wrong field
    when he was young.
  583. CI: Well, I talked to people
    like Caroline Porco
  584. and she said it's like child-rearing.
  585. You've got to set aside
    an 18-20 year timespan
  586. to do something like Cassini
  587. I'm just a bit too much of an
    instant gratification kind of person.
  588. I like to go to a big telescope
    get my data, write a paper
  589. and be done within six months.
  590. So it's just impatience
    that's the only thing
  591. I do want to echo
    one thing Nick talked about.
  592. The trajectory, and the swooping
    in and out of the atmosphere.
  593. That's another one of the amazing…
  594. the orbital mechanics
    of the people that do this
  595. in the outer solar system
    or anywhere in the solar system
  596. it's pretty amazing.
  597. Cassini will by the end of it's
    equinox and solstice missions
  598. have done over a hundred flybys.
  599. And they of course
    re-program these in real time.
  600. Once you find out that ???
    is interesting you go back to it.
  601. And I think the closest approach
  602. was 22 km via Iapetus
    and that's incredible.
  603. And that's a billion miles away
    and you're swooping your billion
  604. multi-billion dollar hardware.
  605. NS: And don't forget that this
    was all pre-programmed
  606. weeks or months in advance
  607. because there's no two-way communication.
  608. No one's driving Cassini.
  609. CI: That's right. So, these are really
  610. remarkable feats to be doing,
  611. and the people who do that,
    they must be having a hell of fun.
  612. Just like the guy who was
    was the deputy PI
  613. of the Deep Impact mission.
  614. He was quoted afterwards saying
  615. "I can't believe they're paying us
    to have this much fun".
  616. NS: That's right, and every now and again
  617. somebody will come up to me and say,
  618. "Oh, are you a rocket scientist?"
    and you know, I get a little chuffed.
  619. But then I was put in my place recently
    when somebody said,
  620. "Huh, rocket scientist. I would never get
  621. into a rocket made by a scientist".
  622. It's the rocket engineers
    that really deserve the credit.
  623. You know, we get to go answer
    the big questions
  624. and that's what we consider fun,
  625. but boy, are we ever dependent
    on the ingenuity of the rocket engineers,
  626. and what an amazing job they do.
  627. JM: I have to interject this.
  628. I met a lady, who was an engineer,
  629. and she ended up writing
    a book for children
  630. about engineers, what do engineers do,
  631. because her own 5-year-old
    was looking at, like,
  632. a shuttle launch, or something, and said,
  633. "Oh, wow! Look what scientists get to do"
  634. and she goes "and engineers".
  635. "Engineers are the ones
    who make this actually happen"
  636. so, yeah, is very important.
  637. We don't have an engineer
    on the panel right now.
  638. We got two scientists...
    well, three scientists.
  639. But I don't do space stuff.
  640. Chris, I'd like you to speak quickly
    about this thing.
  641. We send… well, we've had a few
  642. where things have tried to give up,
  643. but then sort of revived themselves,
  644. they're able to work,
    but for the most part,
  645. we send these things out,
  646. and they have an expected lifespan.
  647. But most of the time they seem
    to be exceeding that lifespan.
  648. If you could speak on that,
  649. and what we can do,
    once we've gotten lucky.
  650. CI: And that's natural and good engineering.
  651. Of course, engineers like to have big margins,
  652. and those margins are not always…
  653. For a bridge, or anything,
    it's a factor of two or three.
  654. I think in space sometimes it's even more,
    like an order of magnitude.
  655. So, obviously the twin rovers
  656. poor Steve talking about Mars time,
  657. poor Steve Squires has been
    living Mars time for a decade,

  658. and he was only supposed
    to do that for three months.
  659. Because the second
    of his rovers is still working.
  660. There is another wonderful example.
  661. The Pioneers and the Voyagers
    now leaving our messages in a bottle,
  662. tossed into the outer solar system.
  663. They're putting out.
  664. Their plans are reduced to a fraction
  665. of a Watt of transmitted energy,
  666. but we've got big enough
    telescopes like Arecibo
  667. to detect that at a distance
    of billions of miles.
  668. These again, Ed Stone, whose at JPL,
  669. he's into his 80s, I think,
    and these missions
  670. are outlasting all of their investigators,
    some of them.
  671. And that's fine,
  672. because they're still returning
    useful data, and it's great.
  673. The problem, of course, is the project,
  674. and the money, and the funding
  675. sort of implies an ending point,
  676. and so it's horrible
    when you face the prospect
  677. of having to switch something off
  678. that's still working,
    or just not look at the data,
  679. or not run the instruments anymore.
  680. And those are real situations
  681. because, obviously,
    you can't start new things
  682. unless you stop doing
    some of your old things.
  683. JM: I'm going to move back.
    Thank you for that, Chris.
  684. I'm going to move back
    over to Nick about…
  685. So what will you do when you're
    past the one-year mark?
  686. Will it depend on funding?
  687. Will you still maintain
  688. the communications
    with the rovers on the surface,
  689. or pair up with ESA
    for future projects, or what?
  690. NS: The one thing we know for sure
    after our first year,
  691. is that MAVEN will be kept
    alive and operating
  692. to serve as a relay for the rovers
  693. for absolutely as long as possible.
  694. And obviously, the current rovers,
  695. and there's another one
    arriving in Mars 2020,
  696. but whether or not MAVEN
    is also doing science
  697. remains to be seen
  698. Every NASA mission, whether it's
    the Hubble Space Telescope
  699. or the rovers, after 90 days,
  700. goes through a very careful process
  701. where the team says,
    if you give us more money,
  702. here's the science that we can do.

  703. And so, they're thoughtful decisions,
  704. albeit with a tight pocketbook
  705. And so, we'll go through that process
    called "Senior Review"
  706. probably a handful of months
    before the end of our first year
  707. and we'll make the case saying,
  708. if you allow us to keep
    making measurements
  709. here's the science that we can accomplish
  710. It's a fabulous spacecraft.
  711. It's got excellent instrumentation on it,
  712. and I'm sure we'll make a very good case,
  713. but it'll be up to a bunch of people
    making these difficult choices.
  714. JM: How many instruments are on MAVEN?
  715. NS: You know, the truth is,
    I can't remember if it's eight or nine,
  716. but it's a bunch
  717. and some of them are designed
    for measuring the waves and the fields.
  718. Some of them are designed
    for the charged particles.
  719. Some for the neutral particles
  720. We're for photons, and some have two parts
  721. and some have three,
    and so that's why I can't quite keep track.
  722. Basically, we have enough instruments on,
  723. that an atom and molecule
    can't get away from Mars
  724. without us having a handle
    on that process.
  725. JM: We've noticed that.
  726. Chris, so, reading your book,
    I got the sense,
  727. the average seems to be a dozen.

  728. There's at least a dozen
    on every probe we send out.
  729. Would you say that's true?
    Did I get that right?
  730. CI: Yeah, a lot of mass emissions now
    are likely Swiss army knives.
  731. They have large numbers
    of instrument teams combining
  732. and Cassini is a classic example
  733. that these are
    multi-billion dollar missions.
  734. Hubble is an example,
    great space observatories,
  735. but NASA's also had enormous success
  736. with more specialized
    single purpose missions.
  737. My favorite two examples, of course,
  738. are Keplar, as it's PI, Bill Burouki,
    famously said,
  739. "it's the most boring mission
    you could possibly imagine".
  740. It's designed to take a picture
    of the same piece of sky,
  741. every six minutes, for years,
  742. and that's all it does.
  743. It's how dull?
  744. And then WMAT,
    a completely different concept.
  745. A sort of microwave satellite
    looking at the early universe
  746. also just doing a very simple thing,
  747. just scanning the sky,
    over and over and over again,
  748. drilling down in the systematic
    and random errors
  749. to make a microwave map,
  750. and that's all it can do
    but it's incredible.
  751. Those two missions hit,
  752. which cost a fraction of a billion dollars,
  753. more like, 100 million, say,
    which is of course not cheap.
  754. They do one thing exquisitely well.
  755. So there's sort of two ways to go
    with all of these missions
  756. JM: Now MAVEN,
    there were a lot of questions
  757. about cost in the press conference
    yesterday.
  758. Do you remember some
    of those numbers, Nick?
  759. NS: No, and I missed the last part
    of this press conference.
  760. Scientists you'll learn remember numbers
    to a factor of two, or so.
  761. But we have, of course, teams of people.
  762. The engineers are
    a little more precise in that.
  763. And the budgeteers more precise still.
  764. All I know is that MAVEN has not
    raised the alarms of cost overruns.
  765. We have a principle investigator
    who's made some hard choices,
  766. especially early on
  767. about how we're going
    to keep this mission from over-running.
  768. This is a real… the mark of what
    are called "PI-led missions"
  769. Principle Investigator Led Missions,
  770. where it's really on one person's plate
  771. to make sure that
    this is going to perform,
  772. do the science, and not overrun in cost.
  773. So the MAVEN definitely goes
    in the plus column
  774. and being in the university setting
  775. is one of the ways
    that we've really been able
  776. to keep the cost down,
  777. and we sure wish that
    more opportunities like this
  778. would be coming down the pike
  779. CI: These are hard tradeoffs too,
  780. because sometimes an idea comes along
  781. that you really want to add in
    to your instruments
  782. so it gives you a new capability,
  783. and you've got to fit it
    under that cost curve.
  784. The famous example I like,
  785. is that the Vikings were not
    originally designed with cameras.
  786. And Carl Sagan argued, he said
  787. "We're going to look really foolish
  788. "if there are polar bears on Mars
  789. "and we didn't have a camera
    to take pictures of them".
  790. He was joking, but his point was taken,
  791. and so the Vikings had cameras,
  792. and it's the evocative image
    of the surface of Mars

  793. that caught everyone's attention.
  794. And then fast-forward to Curiosity,
  795. and this was unfortunately a failed attempt.
  796. James Cameron was part of that project,
  797. and he was on the verge of having a design
  798. for an HD video camera
    to be part of Curiosity.
  799. It just couldn't make it under the wire
  800. of getting all specified and locked down
    before the launch,
  801. so Curiosity did not have
    the James Cameron connection.
  802. But keeping these possibilities in play
    is really important,
  803. even if it's a tough budget decision.
  804. NS: So, MAVEN by the way,
  805. does not have
    a visible light camera on it.
  806. When you think about
    the technology that's there
  807. for Mars reconnaissance orbiter,
  808. every camera has to be better
    than the one before.
  809. With all these other instruments
    that we have onboard,
  810. we couldn't take an even better camera.
  811. But we'll be sending back
  812. some pretty cool images and movies
  813. of the planets at the ultraviolet,
  814. and that'll be a new contribution.
  815. Not so many megapixels though,
    not scientifically important.
  816. JM: I'm actually wearing,
    I'll have to come up closer.
  817. I'm actually wearing a necklace
  818. by this gal whose fascinated with Mars
  819. and this is Curiosity's
    first photo on Mars.
  820. So, she's taken iconic images
    that have been taken on Mars
  821. by Viking and all that
    she's then turned into jewelry,
  822. and I love wearing them because
    they are conversation pieces.
  823. So my little contribution
    to spreading the excitement
  824. of space exploration to the rest of the world.
  825. Let me just… There was a question
    I wanted to ask.
  826. Chris, is there anything else
    you'd like to add to this conversation
  827. of the larger picture
    of space exploration?
  828. CI: Well, I'll just make a guess
    for the future,
  829. which is that we're at a sort
    of interesting transition point
  830. in space exploration
    of the solar system or beyond
  831. or even of space astronomy,
  832. where we see this nascent private
    space industry, which is emerging.
  833. Just as well, since America can't get
    astronauts up into orbit, anyway.
  834. We depend on the Russians,
  835. and now we're going to depend
    on the private sector.
  836. I think that's going to start playing out
  837. in the business we've been talked about.
  838. Remember there are
    a thousand billionaires on the Earth,
  839. and any one of them could fund
    a really cool planetary probe.
  840. So if NASA gets stock on sending
    that Hydrobot to Europa,
  841. or going back to Titan
    with the dirigible technology,
  842. I think some billionaires might step in,
  843. and I think the whole game
    is going to get more interesting.
  844. It's kind of limiting
  845. when only a couple
    of governments are doing it
  846. and the governments
    get shutdown occasionally,
  847. and they have tough budget
    choices and so on.
  848. I think it will be more of a wild west,
  849. but there's going to be some
    really cool things that happen
  850. when the private sector and entrepreneurs
  851. actually start doing this stuff.
  852. JM: So, here's a question.
  853. Any idea how many project ideas
    are out there,
  854. and what percent actually happen?
  855. NS: It's a small fraction.
  856. Every time NASA has an announcement
    of opportunity with open categories,
  857. there tend to be dozens of missions
  858. for every one or two that are selected.
  859. And it's a different set of dozens
    for every opportunity.
  860. So, pretty soon, that's going to be
  861. hundreds of ideas that we're not doing.
  862. And I can't promise that
    they're all good or feasible
  863. with the current technology,
  864. but far more good and practical missions
    are not chosen
  865. because a nation hasn't found
    the will to fund it.
  866. CI: I agree. I mean, in some competitions
  867. you go down from 100 to 25 to 4 to 1,
  868. and the engineering,
    we've talked about the engineering,
  869. which is exquisite, and these
    are technically feasible.
  870. That almost never is the issue
    of why they weren't chosen.
  871. So, it really is more the will
  872. the money, the priorities and so on,
  873. which is why I think
    if there are more players
  874. some of these things
    that are sitting there on the shelf,
  875. NASA has the designs on the shelf,
  876. will actually happen.
  877. NS: Let me change from the billionaires
  878. that Chris talks about
    to the billion kids on the planet,
  879. almost all of whom are excited about space.
  880. And space is really the gateway,
  881. I think the best gateway
    to stem education.
  882. It's really important that we keep
    this space program going.
  883. It's now an international effort,
  884. so many nations participating to have this
  885. really excite the next generation.
  886. And before the viewers get discouraged
    about the state of affairs
  887. where we can't do
    everything that we want to,
  888. I want everybody to realize that everybody
    can play a part in this.
  889. And I think spreading the word about
  890. what NASA's big handful
    of operating missions are doing,
  891. if you have access to…
  892. If you are comfortable go out
    and volunteer in a classroom.
  893. Go make sure your taxi driver
  894. or your waiter or waitress
  895. know what's going on in space.
  896. Make this part of everyday conversation
  897. so people want to know what's next.
  898. What are we doing?
  899. Because in the big picture
    of the federal budget,
  900. this is not an expensive proposition
    that we're talking about.
  901. We just need to raise everybody's awareness
  902. that this is affordable and exciting
  903. and it paves the way for the next generation.
  904. JM: So actually, you guys
    will be happy to hear
  905. that I have feedback from my twitter feed
  906. and from my Google+ that we have
    a couple classrooms
  907. watching us right now.
  908. I'm so happy that teachers
    saw this and said,
  909. let's just share about this.
  910. The other thing… I do remember a question,
  911. and to me the answer seems obvious,
  912. but here's a question someone
    on my twitter feed asked yesterday.
  913. "So why are we going back to Mars?
  914. "Why not set our sights on an already
    predetermined Earth-like planet
  915. "that is way out there, an exoplanet?"
  916. So why Mars?
  917. NS: I'll do the "Why Mars?" again,
  918. and then I'll let Chris talk
    about the next exoplanet.
  919. We're doing Mars again because
  920. what MAVEN is doing there
    has never been done before.
  921. There's never been a mission
  922. that's basically looking at
    where the atmosphere goes.
  923. We've sent a large number of missions
  924. that figured out that there was
    a greater atmosphere in the past,
  925. but this is just about the biggest
    mystery on Mars, nowadays.
  926. Where did the atmosphere go?
  927. And none of the operating
    missions can do that.
  928. We've got to go back.
  929. CI: And I would also,
    just to echo and Segway,
  930. I would say that there's so much
    still to learn on Mars,
  931. and Mars is indeed potentially
    a habitable planet under the surface,
  932. so we need to figure that out.
  933. And we will always learn so much more
  934. about a planet in the solar system,
  935. than any exoplanet, however nearby.
  936. It's just there's no comparison.
  937. However, what happens to a planet,
    because planets evolve and change
  938. and Mars is the great example
  939. is going to be true elsewhere too.
  940. And so, as we start looking at our bodycount
  941. of habitable and Earth-like planets
  942. from Kepler and other missions,
  943. the context for understanding them
  944. when we have very little data,
    really we just have a size or a mass,
  945. and almost no other information
  946. our context for understanding them
    is still the solar system,
  947. is still the terrestrial planets,
    much closer to us
  948. NS: We must develop the capability
  949. to characterize those planets in greater detail.
  950. James Webb's space telescope
    will start to do that,
  951. but it's a big technological challenge.
  952. And, lot's of our favorite
    engineers and designers
  953. are working on it,
  954. but at present it's a pretty
    expensive proposition.
  955. It's actually considerably cheaper
    to continue learning more
  956. within our own solar system
  957. than it is to learn in great detail
  958. about the wealth of worlds
    that we now know are out there.
  959. JM: So, we've been talking,
    a little over 45 minutes.
  960. I would like to give both of you
    an opportunity
  961. to express anything else
  962. you'd like to express to our audience
  963. or maybe something
    I completely forgot to ask,
  964. and then we will wrap things up.
  965. So why don't we start with Nick?
  966. NS: No, no, go to Chris
    while I'm trying to…
  967. JM: Go to Chris.
  968. CI: Well, I just want to echo something
  969. that we've touched on a few times,
    which is, it feels like
  970. solar system exploration,
    study of planets nearby,
  971. is a mature subject
  972. that we've learned most
    of what we might want to learn,
  973. and that just simply isn't the case.
  974. Even with our close neighbour Mars,
  975. there're just a ton
    of questions and mysteries.
  976. And when we get to all those others,
  977. the best guest is there're probably
  978. a dozen habitable spots
    in the solar system,
  979. mostly in the outer solar sysem.
  980. And we're almost
    completely ignorant of those.
  981. And so when it comes to going
    to Titan or Europa
  982. or these really fascinating destinations,
  983. our level of ignorance
    is still almost complete.
  984. So it's still early days, actually,
    for solar system exploration,

  985. and especially in the context of biology,
  986. and where we might find it
    in the universe.
  987. NS: And if I could just step back
    for a broad perspective,
  988. Carl Sagan said,
  989. "There's one generation that gets
  990. "to experience this transition of planets
  991. "as points of light,
    to worlds in their own right".
  992. And men are ever getting a close look
  993. at these worlds with the latest
    generation of spacecraft.
  994. My brother's a political scientist,
  995. and he once said to me that
  996. "Everything that I said
    is going to be forgotten
  997. "in decades or 100 years,
  998. "but this transition of humans
    becoming spacefaring,
  999. "this is going to be remembered
    for 1000 years."
  1000. People will talk about this age,
  1001. and so for all of us
  1002. to appreciate this incredible time
    that we live in,
  1003. and this opportunity
    that we are given to participate.
  1004. Get everybody onboard.
  1005. Spread the word.
  1006. This is a real halmark of the age
  1007. that we have the privilege of living in.
  1008. JM: That's amazing. My final question:
  1009. When are we sending humans to Mars?
  1010. NS: When I was growing up
    I said I wanted to go to Mars
  1011. and raise chickens to find out
  1012. if they would grow larger in low-gravity.
  1013. It's become clear to me
    that I won't have that opportunity.
  1014. I would love it, if one of my kids
    had that chance.
  1015. I sure hope it doesn't go down
    to the generation beyond that.
  1016. It's sometimes said that it's too expensive
  1017. to send humans to Mars,
  1018. but our nation has
    apparently found the will
  1019. to spend that much money
    on other projects
  1020. that I think, will not be remembered
    in a thousand years,
  1021. and I would love for this effort
    to change the focus of our nation,
  1022. and even the efforts of the world
  1023. to make that next grand step
  1024. because I think that it is human destiny.
  1025. Robots lead the way, but humans
    can and must follow.
  1026. CI: And to answer your question directly
    we're talking 20+ years.
  1027. And then again I think the private sector
  1028. is already starting to step up
    and make ideas.
  1029. For instance,
    there's a well-publisized idea
  1030. for a one-way trip,
    which'd obviously save some money.
  1031. NASA first was outed on having
  1032. a very similar idea
    sitting on their shelf,
  1033. but it's not good PR for NASA
  1034. to send astronauts of to die on a…
  1035. NS: Yeah, I actually think that the space frontier
  1036. will be conquered by humans,
  1037. when humans are allowed
    to take the same kinds of risks
  1038. that they took when moving
    to Colorado and California,
  1039. when coming to the American west.
  1040. Individuals took risks.
  1041. Many of them lost their lives doing it
  1042. but the way that they opened
    for the rest of us
  1043. we'll remember forever.
  1044. I think it's like Chris says.
  1045. It's going to be the private sector
    and individuals taking risks
  1046. that will allow us to cross that frontier.
  1047. IC: And if you want to evoke
    the multi-generational future,
  1048. I recommend Kim Stanley Robinson's
    Mars trilogy,
  1049. Mars: Red, Green, and Blue.
  1050. Amazing evocations,
    not just of people on Mars,
  1051. but of the geology
    and the atmosphere, and so on.
  1052. They are mesmerizing books.
  1053. JM: Thanks for the book recommendation
  1054. because that's one of my platforms.
  1055. I love to get people to read.
  1056. Thank you gentlemen for your input today.
  1057. And thanks to the MAVEN team.
  1058. We will wait for the anticipated launch.
  1059. But thank you guys for a project
  1060. that's on budget, or under budget,
  1061. and on time, or under time,
  1062. and you guys are just meeting
    all these hallmarks
  1063. and making people happy.
  1064. They'll want to hire you again
  1065. NS: That's right. And let's go answer
    some more big questions.
  1066. JM: Well, thank you very much,
  1067. all of you out there
    in the audience for joining us
  1068. for this very enlightening
    discussion about MAVEN.
  1069. And don't forget, we're looking out
    towards November 14th
  1070. for Chris Hatfield to join us.
  1071. So, if you didn't hear,
    his book is out today.
  1072. So, if you want to pick that up
    and join us here
  1073. November 14th at noon
    for a Scientific American chat with Chris.
  1074. We'll get more of the human side
    of space travel,
  1075. and today, of course,
    we were just talking
  1076. about unmanned, or robotic, space travel.
  1077. So, thank you, Chris, and thank you, Nick
  1078. NS: So long, everybody.
  1079. CI: Bye.