Latest / Star Trails: From Backyard Astronomy to Cosmic Wonder / The Invisible Architecture of the Universe, with Dr. Enrique Lopez Rodriguez

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The Invisible Architecture of the Universe, with Dr. Enrique Lopez Rodriguez · Star Trails: From Backyard Astronomy to Cosmic Wonder

• 0:07
  Howdy Star Gazers and welcome to this episode
• 0:10
  of Star Trails. My name is Drew and I'll be your
• 0:13
  guide to the night sky for the week of April
• 0:15
  the 26th to May 2nd. This week we're exploring
• 0:20
  a side of the universe you can't see, at least
• 0:23
  not directly. I sit down with Professor Enrique
• 0:27
  Lopez Rodriguez, one of the leading researchers
• 0:30
  in the United States studying magnetic fields
• 0:33
  and galaxies, to talk about the invisible structures
• 0:36
  that shape the cosmos. Later in the show, we'll
• 0:40
  take a look at this week's night sky. Whether
• 0:43
  you're tuning in from the backyard or the balcony,
• 0:46
  I'm glad you're here. So grab a comfortable spot
• 0:49
  under the night sky and let's get started. We
• 0:56
  tend to think of galaxies as massive collections
• 0:59
  of stars bound by gravity pinwheeling through
• 1:02
  space. But beneath that visible structure there's
• 1:06
  something else at work. Invisible magnetic fields
• 1:10
  stretching across thousands of light years that
• 1:13
  are quietly shaping how galaxies evolve. In fact,
• 1:17
  as you're about to hear, galaxies don't exist
• 1:20
  in isolation at all. They can exchange material
• 1:24
  across vast distances guided along these magnetic
• 1:28
  pathways. And at the centers of many of these
• 1:31
  galaxies are supermassive black holes, some actively
• 1:36
  consuming matter and blasting energy back into
• 1:39
  space, and others, surprisingly, almost dormant,
• 1:43
  as if they've simply shut down. In this episode,
• 1:47
  we'll step behind the curtain and meet one of
• 1:49
  the researchers helping us understand the hidden
• 1:52
  structure of the universe. Today's guest is Professor
• 1:56
  Enrique Lopez Rodriguez, an extra -galactic astronomer
• 2:02
  at the University of South Carolina, and one
• 2:05
  of the leading researchers in the United States
• 2:07
  studying magnetic fields and galaxies. Originally
• 2:11
  from the Canary Islands, his work focuses on
• 2:14
  how these invisible fields influence the evolution
• 2:17
  of galaxies, the behavior of supermassive black
• 2:21
  holes, and the flow of matter across cosmic scales.
• 2:27
  He's led major international research efforts,
• 2:30
  including a NASA -Sofia legacy program to map
• 2:34
  magnetic fields in nearby galaxies and has published
• 2:38
  nearly 90 peer -reviewed papers in journals like
• 2:42
  the Astrophysical Journal, Monthly Notices of
• 2:45
  the Royal Astronomical Society, and Nature Astronomy.
• 2:49
  And as you'll hear, his work is helping us uncover
• 2:52
  a part of the universe that may be shaping our
• 2:56
  reality. Here's my interview with Professor Rodriguez.
• 3:03
  Enrique, thanks for taking the time to speak
• 3:05
  with me today and welcome to the show. Well,
• 3:07
  thank you for having me. Tell me a little bit
• 3:09
  about yourself. How did you get into astronomy?
• 3:12
  Okay, I'm originally from Spain, the Canary Islands,
• 3:15
  these small islands close to South Morocco. The
• 3:19
  islands are volcanic in the same way that you
• 3:22
  think about Hawaii to the U .S., the Canary Islands
• 3:25
  to Spain. And these islands are very famous in
• 3:29
  astronomy because we have an international observatory
• 3:31
  there. Actually the largest telescope in the
• 3:33
  world is in the Canary Islands. So therefore
• 3:37
  we have a really good skies, like really, really
• 3:39
  good skies. I was also very lucky that the university
• 3:44
  in my hometown had a physics degree, so I didn't
• 3:48
  have to move because I was not able to go anywhere
• 3:51
  because my family didn't have enough resources
• 3:53
  to send me to another school. So then I did my
• 3:57
  bachelor in the Canary Islands. And then one
• 4:01
  of my professors told me about this exchange
• 4:06
  of grad students from the Canary Islands to the
• 4:09
  University of Florida. Lucky me, the chair of
• 4:13
  the Department of Astronomy in the University
• 4:15
  of Florida was from Spain. So I have a phone
• 4:18
  call with him. And then I think a month later,
• 4:21
  I was in Florida, just doing the PhD there. Well,
• 4:25
  so you come by it honestly you had very dark
• 4:27
  skies growing up and it inspired you. Yeah. Yeah.
• 4:30
  Yeah, that was a very very interesting there
• 4:33
  Well, let's get right into it. You're an extra
• 4:36
  galactic astronomer. Can you tell us what that
• 4:39
  means? Because that is a fascinating term. Yeah,
• 4:41
  so I'm basically study the galaxy evolution.
• 4:46
  So I'm interested to know how galaxies form,
• 4:49
  what are the compositions, and then how they
• 4:52
  evolve from the beginning of the universe to
• 4:55
  nowadays. How did you get into that? That is
• 4:57
  a very specific field. So when you think about
• 5:02
  the universe, the main most common objects besides
• 5:08
  stars are galaxies. And then we always hear from
• 5:12
  the news or when you read books about the universe
• 5:15
  is expanding. Einstein have their general relativity
• 5:18
  that explain the whole universe. They're like,
• 5:20
  all right, so this interesting, but what's inside
• 5:24
  of this universe? And we know. we see people
• 5:27
  here, we see cars, we see stars, we see the planets,
• 5:30
  but then you start getting more interested, like
• 5:32
  what is beyond that? and you see that beyond
• 5:34
  the solar system is more stars. And beyond more
• 5:38
  stars is all inside of objects that we call galaxies
• 5:41
  that are all gravitationally bound by the motion
• 5:45
  of stars orbiting around the center of the galaxy.
• 5:48
  And then when you go beyond that, you see there's
• 5:51
  no single galaxy that we live. It's like thousands
• 5:54
  of them nearby to the Milky Way. You go a little
• 5:57
  bit larger and zoom out and say, okay, it's several
• 6:00
  trillions of galaxies moving in inside of space,
• 6:04
  and they're all moving away. Like, okay, now
• 6:06
  I want to know about this. So like, I want to
• 6:08
  know about the big picture, how this even form,
• 6:11
  are galaxies the same? They're not, why they
• 6:14
  are different? and what they make them different,
• 6:17
  and then how galaxies collide to each other,
• 6:21
  or how they destroy each other, how they form,
• 6:23
  and then I get into a rabbit hole, and I've been
• 6:26
  in that rabbit hole for the past 20, 30 years
• 6:29
  until now. And that rabbit hole is the study
• 6:32
  of how magnetism affects galaxies, correct? Yeah,
• 6:35
  exactly. So then you have another level here.
• 6:39
  So normally when we observe galaxies or the universe
• 6:43
  around us, we observe the radiation, the photons
• 6:48
  emitting from these stars, for example. But electromagnetism
• 6:53
  tells us that if you have charged particles moving,
• 6:57
  those charged particles generate a magnetic field.
• 7:00
  And those magnetic fields cannot be destroyed
• 7:02
  because monopoles don't exist. So then like you
• 7:06
  cannot destroy, the only thing that you can do
• 7:08
  is amplify them, meaning that you have more magnetic
• 7:13
  field lines per volume, or you can dissipate
• 7:15
  them. And that means that you spread the magnetic
• 7:18
  field in a larger volume, but you cannot completely
• 7:21
  destroy them. So that means like, okay, so if
• 7:23
  we are in a permeated magnetized universe what
• 7:28
  is the effect of this magnetic field so how the
• 7:30
  magnetic field affect the formation of stars
• 7:33
  how affect the dynamics of the of the gas how
• 7:37
  affect the accretion onto supermassive black
• 7:39
  holes. So I got more interested into that because
• 7:43
  you have the connection between physics that
• 7:46
  you can explain in the lab by a magnet and you
• 7:48
  put the iron dust around. And then you also connect
• 7:53
  the astronomy side, like how stars form. And
• 7:56
  then I've been for the past 15 or 20 years trying
• 8:00
  to estimate what is the effect of the hematic
• 8:02
  field. in the dynamics of the gas into supermassive
• 8:07
  black holes in the center of galaxies or in star
• 8:10
  formation and it looks like that they're very
• 8:13
  very very tiny energy of magnetic fields but
• 8:16
  they're extremely important to explain how stars
• 8:20
  form, for example. Well, you mentioned it yourself,
• 8:22
  galaxies are these groups of stars bound together
• 8:25
  by gravity and astronomy. We talk about gravity
• 8:28
  all the time, and gravity is not that I can do
• 8:31
  it, but relatively simple to calculate if you
• 8:34
  know the mass of something. How do you calculate?
• 8:36
  magnetism from afar like this. Right, yeah, so
• 8:40
  exactly. Well, gravity is the one that governs
• 8:42
  the whole formation of stars. For example, you
• 8:44
  have a mass and gravity makes them to collapse.
• 8:47
  OK, so now how do you measure magnetic fields?
• 8:50
  So we don't, we cannot send a manectometer anywhere.
• 8:54
  So what we observe is the effect of magnetic
• 8:57
  fields in material. For example, let's say that
• 9:00
  you have an electron. An electron is a charged
• 9:03
  particle with negative charge. So if you have
• 9:05
  a magnetic field, those electrons need to move
• 9:08
  along the magnetic field orientation. So have
• 9:11
  a specific trajectory, and these electrons are
• 9:14
  spinning around the magnetic field. So then we
• 9:17
  can measure that direction of the electrons that
• 9:21
  give you a specific signature electromagnetic
• 9:23
  wave. And then... measuring that signature that
• 9:26
  we call polarization, we can say, okay, this
• 9:29
  electron is not freely moving in space, it's
• 9:32
  moving along some direction, and then we can
• 9:34
  infer the molecular strength and the orientation
• 9:37
  of it. This is one way. And then the other way
• 9:40
  that I'm using for the past 10 years, I use dust.
• 9:44
  And dust is organic compounds made of carbon,
• 9:49
  nitrogen, oxygen, silicates, and iron. And these
• 9:53
  compounds are like micrometer size. And because
• 9:57
  they have iron, they align with the local magnetic
• 10:01
  field. Let's imagine that you have a lot of rice
• 10:04
  grains. And they're elongated, right? And these
• 10:08
  rice grains have irons inside. So then if you
• 10:12
  put a magnet around, they will all... aligned
• 10:15
  with the local magnetic field. And this is exactly
• 10:17
  what I'm observing in very far away galaxies.
• 10:21
  I see all this dust aligned with local magnetic
• 10:23
  field. This reminds me of, of course, the elementary
• 10:26
  school science experiment. You put a magnet down
• 10:28
  and put a piece of paper on it. Exactly. Put
• 10:30
  some iron filings and you see the pattern of
• 10:33
  the magnet. Exactly. Exactly. Exactly. You don't
• 10:35
  see the magnetic field. You see the effects of
• 10:39
  the magnetic field in matter. And this item that
• 10:43
  you mentioned is exactly what I observed. in
• 10:47
  galaxies. And how are you observing that from
• 10:49
  so far away? These dust grains have a very interesting
• 10:53
  property. So they're micrometer size. They're
• 10:56
  very close to stars. And the stars are radiating
• 11:00
  energy, mainly in the optical and ultraviolet.
• 11:05
  And then these dust grains absorb all that radiation.
• 11:09
  And when they're absorbing, they get heated.
• 11:13
  So then they have some temperature. have a temperature,
• 11:17
  then they are emitting radiation, because it's
• 11:19
  a black body radiation. So then if they emit
• 11:23
  a radiation, the only thing that we need to do
• 11:25
  is to build an instrument that is sensitive to
• 11:28
  that specific temperature, and then we can observe
• 11:31
  the radiation from those dust grains. Fantastic.
• 11:34
  Now, what instruments are you using to accomplish
• 11:36
  this? Yeah, so many years ago, I used to work
• 11:39
  for NASA. So it's a project called SOFIA, so
• 11:43
  the Stratospheric Observatory for Far -Infrared
• 11:46
  Astronomy. So we had an instrument called HOGPLAS,
• 11:50
  and this instrument is very, very sensitive to
• 11:53
  cold temperatures. And with this instrument,
• 11:55
  we put it in the back of a Boeing 747, very highly
• 11:59
  modified Boeing 747, all German. engineering
• 12:03
  because the Germans are the great engineers that
• 12:06
  collaborate with NASA and they were used to fly
• 12:09
  at 45 ,000 feet over the sea level. And the reason
• 12:12
  is because you need to go outside of the atmosphere.
• 12:17
  and cheaper than sending a spacecraft. So then
• 12:21
  we had this new instrument. We didn't know that
• 12:23
  works, so you cannot send it to space. It's all
• 12:26
  exploratory work. And the idea was to exactly
• 12:29
  observe magnetic fields in the universe. So we
• 12:31
  put it in the back of Boeing 747. We flew in
• 12:34
  the stratosphere a few hundred times. And then
• 12:37
  we took observations of nearby galaxies. Since
• 12:41
  day one, we start tracing those magnetic fields
• 12:46
  at large scale. So we see that this very tiny
• 12:49
  fraction like micrometer size are able to, dust
• 12:53
  grains are able to provide us the information
• 12:57
  of magnetic fields of several thousands of light
• 13:01
  years. So we are doing microscopic physics. to
• 13:04
  get microscopic tracer automatic fields. Speaking
• 13:08
  of working for NASA, I've seen your name attached
• 13:10
  to some images that I've seen on NASA's website,
• 13:13
  and I believe these are the images that show
• 13:15
  a galaxy, and you can almost see those magnetic...
• 13:18
  lines that are sort of superimposed on that.
• 13:22
  So that data collection you're talking about
• 13:24
  is how you produce those images. Yeah, exactly.
• 13:26
  So I have a program called Salsa. It's coming
• 13:28
  from my Spanish heritage. I wanted to call Salsa.
• 13:32
  It's the SOFIA survey for astronomical magnetism.
• 13:36
  I got archival observations previously done by
• 13:40
  NASA in the optical to see the stars, in the
• 13:44
  UV to see the star formation, in the infrared
• 13:47
  to see the dust. I combined them, all real observations.
• 13:50
  And then on top of that, I put the magnetic field
• 13:53
  orientation. It looks like the starry night of
• 13:57
  Van Gogh. There, right away, you can see, for
• 14:00
  example, the galaxy's spiral, you see spiral
• 14:03
  magnetic field. And then you see the spiral is
• 14:07
  more chaotic exactly in the region that you have
• 14:09
  star formation. So now just visually you say,
• 14:12
  oh, something going on here. So why I don't see
• 14:15
  this spiral. And then you go further and say,
• 14:17
  oh, the star formation is tangling or disturbing
• 14:21
  the magnetic field. And now like, all right,
• 14:23
  so then should be a relationship between how
• 14:26
  the star formation is doing in the terrestrial
• 14:29
  medium with what we know with the weather tech
• 14:32
  field. Well, I love that you mentioned Van Gogh
• 14:36
  because when I looked at those, I thought they
• 14:38
  do look like artwork. I don't know if you've
• 14:40
  ever thought about it, but you should blow some
• 14:42
  of these things up and do a gallery exhibition.
• 14:44
  I should, I should. You should do that. Yeah,
• 14:47
  I need to do that. They're really beautiful images.
• 14:50
  And of course, the galaxies themselves are beautiful,
• 14:52
  but then being able to see that dynamic. of the
• 14:55
  magnetism that you've traced on there, it's really
• 14:57
  incredible. And you're right, they follow the
• 14:59
  spirals. And well, that's a good place to talk
• 15:03
  about talking about centers of galaxies, because
• 15:05
  that's something you specialize in as well. Right.
• 15:08
  Yeah. So what we can do is like we can observe.
• 15:12
  galaxies that like, for example, spiral galaxies,
• 15:15
  they're very quiescent, but they're very normal,
• 15:18
  normal between quotation marks. And then we know
• 15:21
  that you have spirals and there is not much star
• 15:23
  formation. And this, you can use it as a sample,
• 15:27
  as a control sample. And then from there you
• 15:29
  can get more exotic, meaning you can go to galaxies
• 15:33
  that has a lot of star formation and is creating
• 15:37
  a lot of supernovae. uh explosions in this case
• 15:40
  when you compare it with the spiral trying to
• 15:42
  have a spiralmatic field now you have the magnetic
• 15:45
  field to be pushed away from the galaxy and i
• 15:47
  was like whoa okay so you have 10 20 super novice
• 15:51
  that is exploding in the center of the galaxy
• 15:54
  and they're not only pushing dust and gas outside
• 16:00
  the galaxy is also dragging the magnetic field
• 16:02
  away from the galaxy. And now like, okay, now
• 16:05
  it's not only the galaxy, it's also the surrounding
• 16:07
  environment of the galaxy is also magnetized.
• 16:10
  All right, okay, now we know that you have magnetic
• 16:13
  fields in the intergalactic medium. And again,
• 16:17
  if you have charged particles, they have to move
• 16:19
  through those magnetic fields so they can move
• 16:22
  freely. So now we know that we can trace in the
• 16:27
  magnetic field, we know how the material flows
• 16:30
  from galaxy to galaxy. That's one way. Then you
• 16:32
  can get more exotic took, and then you can get
• 16:35
  galaxies merging, and you have two galaxies in
• 16:38
  interaction. And they're like, okay, how the
• 16:40
  interaction make the, what happened with the
• 16:43
  magnetic field? And when you see these interacting
• 16:46
  galaxies, maybe... they grab one of the spiral
• 16:50
  arms and stretch and compress and then you see
• 16:53
  the magnetic field also are stretching and compress
• 16:56
  and you have like a bridge between those two
• 17:00
  galaxies with a very strong magnetic field connecting
• 17:03
  both of them. And that means that if you want
• 17:07
  to transfer material from one to another galaxy,
• 17:09
  you need to go through those magnetic fields,
• 17:11
  mandatory. too. So they cannot go and move freely
• 17:14
  and then fall using gravity. They have to move.
• 17:18
  Gravity is taking place, but they have to move
• 17:20
  through those lines. That is incredible that
• 17:22
  there are those connections, because I'm imagining
• 17:25
  we're talking about very, very long distances
• 17:27
  between the two, but yet they make that connection.
• 17:29
  Exactly. Yeah, I mean, we're talking about, I
• 17:31
  mean, our Milky Way. The galaxy that we're living
• 17:35
  is like 15 kiloparsec or so in size. I don't
• 17:39
  know, 30 ,000 years or something like that around
• 17:43
  there. So these two galaxies are like 10, 20
• 17:47
  kiloparsec away from each other. And now you're
• 17:50
  talking about a magnetic field that's connecting
• 17:52
  both of them of the sides of the Milky Way. Wow,
• 17:55
  that's incredible. Some of your... More recent
• 17:59
  stuff is about the idea of these galactic outflows.
• 18:02
  Is that the process you were describing just
• 18:04
  then about how they travel between galaxies on
• 18:07
  these? these waves of magnetism? Yeah, right.
• 18:10
  So exactly. So this is like galaxies, but then
• 18:13
  there are some galaxies that we call active galactic
• 18:16
  nuclei, so AGN. And these galaxies are powered
• 18:20
  by accretion onto a supermassive black hole.
• 18:23
  And this is where my thesis was about. So my
• 18:26
  thesis was about trying to trace the magnetic
• 18:30
  fields surrounding supermassive black holes.
• 18:32
  So the reason behind that is because every single
• 18:35
  model that is playing how matter go into a black
• 18:38
  hole requires the need of a magnetic field, but
• 18:43
  has not been observed yet. And then I'm like,
• 18:46
  okay, if there's some material, maybe this dust,
• 18:49
  I can trace the magnetic field using this dust.
• 18:52
  And I've been doing that for the past 20 years
• 18:53
  or so. I trace the magnetic field so you have
• 18:57
  the supermassive black hole, you have material
• 18:59
  in a disk. orbiting around the black hole, and
• 19:02
  the material is highly magnetized, and I trace
• 19:06
  the magnetic field and I measure the magnetic
• 19:08
  field that looks like a donut shape, like a circle.
• 19:11
  Like a donut. Like a donut, exactly. So, but
• 19:15
  then when we see this arctic -arctic nuclei,
• 19:17
  we see that the agent are also expelling a lot
• 19:21
  of material, and this expel of material we call
• 19:23
  outflows. In the black hole, we always say the
• 19:25
  black hole is a... Nothing can escape the black
• 19:28
  hole, but actually the black holes are very inefficient
• 19:31
  eaters of matter. So actually like 90 % of the
• 19:34
  material that go into the black hole goes away
• 19:36
  in form of energy. So only 10 or less than the
• 19:39
  percent go inside of the black hole. And that
• 19:42
  90 % of energy need to be released somehow. And
• 19:46
  that somehow is due to magnetic fields. So you
• 19:49
  can imagine, for example, solar flares in the
• 19:52
  sun. And then it's a lot of satellites that try
• 19:56
  to figure out how the sun is expelling a lot
• 19:59
  of plasma. And then when you see the very detailed
• 20:02
  images, you see some kind of like arcs. So they're
• 20:06
  called a flare. And these arcs are arcs and then
• 20:09
  these arcs kind of like break and then release
• 20:11
  the energy. Those arcs are created by magnetic
• 20:15
  fields. I feel like I remember seeing that. Yeah,
• 20:18
  the little loops that appear on the Sun's surface
• 20:20
  are created by magnetism. Exactly. And those
• 20:22
  loops open, like break, and release the energy.
• 20:25
  This is exactly what happened in the disks around
• 20:28
  supermassive black holes. You have these loops
• 20:31
  on top of the disks. And then this has the loops,
• 20:35
  the loop break and the release energy. And that's
• 20:38
  what we call outflows. And then those outflows,
• 20:41
  of course, have a lot of energy going out. You
• 20:46
  have supermassive black hole, you have a lot
• 20:48
  of energy, you have a lot of magnetic fields,
• 20:50
  you have a lot of mass, and that outflows can
• 20:54
  do a few things. One is that they don't have
• 20:57
  enough energy to leave the galaxy and then fall
• 20:59
  back. into the galaxy, and then you feed again
• 21:03
  the black hole, or can go into the intergalactic
• 21:06
  medium. So I'm very interested to know how these
• 21:10
  outflows evolve as a function of the power of
• 21:14
  the galaxy. It's amazing to think that they can
• 21:17
  actually escape the gravity of a galaxy like
• 21:20
  that. How does that happen, do you think? Well,
• 21:22
  there's a lot of energy being released, like
• 21:24
  a lot of it. So then it is about what is the
• 21:27
  velocity that you push into the system at the
• 21:31
  beginning when they're released, and the velocity
• 21:34
  is larger than the gravity. The velocity is larger
• 21:38
  than the gravity, so then they can escape. I
• 21:40
  mean, we can send, I mean, not the same, but
• 21:43
  we can send rockets to the moon, right? So we
• 21:46
  put a lot of energy in the back of a rocket to
• 21:49
  push it out. So you can imagine a very extreme.
• 21:52
  case scenario that you have a supermassive black
• 21:54
  hole with a lot of radiation and sometimes you
• 21:57
  push a lot of material away and have enough energy
• 22:00
  to lift the gravitational potential of the black
• 22:04
  hole. Okay and that energy just like you said
• 22:05
  it just dissipates into the into space or gets
• 22:08
  grabbed by something else. Yeah yeah exactly
• 22:10
  can go into the the intergalactic medium the
• 22:13
  medium between galaxies if have enough energy
• 22:16
  or can travel a little bit above and below the
• 22:20
  disk and then fall back due to the gravity and
• 22:23
  at larger distances from the galaxy. And you've
• 22:26
  tracked this at the supermassive black hole at
• 22:28
  the center of our galaxy, correct? Yeah, I do
• 22:31
  our own galaxy, but our own galaxy has a black
• 22:35
  hole that is not creating any material, so it's
• 22:38
  basically dead. The reason is because there's
• 22:41
  no material surrounding the black hole. Maybe
• 22:43
  in the past, the black hole was very active,
• 22:46
  and then it was pushing on the material, but
• 22:48
  right now it's just there, very quiet. And there's
• 22:52
  some material around, but it's not really going
• 22:55
  into the black hole at all. That's amazing that
• 22:58
  black holes... once upon a time being these theoretical
• 23:02
  objects and now you can look at them and say
• 23:03
  well this one's not as active as this one is
• 23:05
  and this one is doing more than that one that's
• 23:07
  incredible i've always been curious so we think
• 23:10
  most galaxies have a black hole at the center
• 23:13
  in some cases is that what force that creates
• 23:16
  the spiral shape of the galaxy itself you think
• 23:18
  yes so we think that most of the galaxies if
• 23:21
  not all has a supermassive black hole in the
• 23:24
  center supermassive means 10 to the six to 10
• 23:27
  to the 9 times the mass of the Sun. So you have
• 23:30
  a million times of a few billion times the mass
• 23:34
  of the Sun inside of the center of the galaxy
• 23:39
  of a size that can fit inside of the solar system.
• 23:44
  So this is the size of the supermassive black
• 23:46
  hole. Okay, so this black hole has a gravitational
• 23:51
  sphere. So meaning like how far away you need
• 23:54
  to be in order to be affected by the gravity.
• 23:58
  And that is only the very, very central part
• 24:02
  of the galaxy. So even though we see spiral galaxies,
• 24:06
  these spirals are not spiraling around because
• 24:09
  of the black hole. It's spiraling around because
• 24:12
  of the angular momentum of the of the disks so
• 24:16
  let's say for example you have a spherical cloud
• 24:19
  does a spherical cloud collapse and when they
• 24:22
  collapse have some rotation and then form a disk
• 24:25
  and that disk start rotating and that's the reason
• 24:27
  why we see the spiral is moving but they had
• 24:30
  nothing to do with the black hole. So it's not
• 24:33
  like this science fiction visualization of a
• 24:37
  black hole out there swirling around like everything's
• 24:41
  swirling down a drain. It's not like that. Yeah,
• 24:43
  in the central part of the galaxy, yes. In our
• 24:48
  distance from the center of the galaxy, we are
• 24:50
  not related with that. Okay, that's fascinating
• 24:53
  stuff. even though we are not affected by the
• 24:56
  gravitational potential of the galaxy, the dynamic
• 25:00
  of the galaxy or the evolution of the galaxy
• 25:01
  depends on what happens with the black hole.
• 25:04
  So the black hole is active, a creating matter.
• 25:07
  So that means a lot of energy being released.
• 25:10
  So that energy can affect the dynamic of the
• 25:13
  galaxy. For example, if our galaxy have an active
• 25:17
  galactic nuclei in the center, we will not be
• 25:19
  here, for example, because so much energy that
• 25:21
  it will destroy the solar system. That is incredible.
• 25:25
  That is incredible to think about. What does
• 25:28
  a modern astronomer do? What does your day look
• 25:31
  like? Because I imagine, especially with the
• 25:33
  work you're doing, you're not looking through
• 25:35
  telescopes maybe at all anymore. So what does
• 25:39
  your day look like? You have an idea, how do
• 25:41
  you chase it? All right, so my position as a
• 25:43
  faculty is a combination of research and teaching.
• 25:48
  right? So the teaching will have several classes
• 25:52
  during the year and then I teach all the way
• 25:55
  from no science majors about what astronomy is.
• 25:59
  For example, in this semester I'm teaching the
• 26:02
  dark universe so it's about or I call it our
• 26:06
  ignorance in the universe. So we don't know about
• 26:09
  dark matter. We don't know about dark energy.
• 26:10
  We don't know about expansion of the universe.
• 26:13
  And then I just show them what all this means.
• 26:16
  And then on my research side is research projects.
• 26:19
  So I have research goals. For example, my overall
• 26:23
  goal is understanding magnetic fields in the
• 26:25
  universe. So I'm an observational astronomer.
• 26:28
  So I use telescopes. So then I normally, during
• 26:31
  the year, I have to apply for observing proposals
• 26:36
  to use a specific telescope all around the world.
• 26:39
  For example, today was the deadline for a telescope
• 26:43
  in Chile. It's called ALMA. Atacama large and
• 26:47
  limited array. And then those ones allow me to,
• 26:50
  for example, observe thematic fields in the early
• 26:53
  universe or very, very close to nearby HGN. So
• 26:57
  I write the proposal, it takes me some time.
• 27:00
  Of course, you cannot go, sadly, you cannot go
• 27:02
  to the Atacama Desert, but they give you the
• 27:04
  data. For example, I also use telescopes in Hawaii,
• 27:11
  in the Canary Islands, Spain, Chile. and South
• 27:17
  Africa. And when you say telescopes, are we talking
• 27:20
  radio telescopes? It's a combination of optical
• 27:24
  telescopes, infrared telescopes, radio telescopes.
• 27:28
  So that means that my day -to -day life is writing
• 27:31
  observing proposals to get new data, to go deeper
• 27:36
  into specific fields, or to do, for example,
• 27:39
  a large sample because I want to have a statistical
• 27:42
  sample of multiple galaxies. and then also I
• 27:47
  have my research team have grad students and
• 27:50
  postdocs so that means I need to find funding
• 27:54
  to support them so that means I need to apply
• 27:58
  for national grants for example the National
• 28:02
  Science Foundation or NASA or some private foundations
• 28:07
  that I gained so I submit some reports and say,
• 28:11
  this is the research that I want to do. It's
• 28:13
  important for whatever reason. And then give
• 28:16
  me, please give me some money so I can pay some
• 28:19
  graduate student for the next two or three years.
• 28:21
  So like you said, you were working with Alma.
• 28:23
  So you get your data back from Alma. What's the
• 28:26
  next step? Oh, the next step is be very excited
• 28:32
  first as I have new data now like what this data
• 28:35
  is about so because like every single time that
• 28:38
  I observe with a telescope in this case ALMA
• 28:40
  they give you new things and you spend the next
• 28:43
  year or two years analyzing the data quantifying
• 28:46
  the data meaning like you have to do a lot of
• 28:48
  statistics to make sure that how robust your
• 28:51
  measurements are and then once you have a result
• 28:56
  or that you are convinced that is in real. So
• 29:00
  then you need to have a interpretation, a scientific
• 29:03
  interpretation of that. And that requires a lot
• 29:05
  of communication with a lot of collaborators
• 29:08
  besides to yourself and the team that I have
• 29:11
  here, like what this all means. And then you
• 29:14
  have a lot of conversation with many people just
• 29:16
  to have a consensus and not be biased by my own
• 29:20
  ideas too. And then when all have, when I have
• 29:24
  a very robust interpretation, so then it's a
• 29:28
  matter of like writing the paper and publish
• 29:30
  it and then show it to the community and then
• 29:33
  see what they but think about it. What has you
• 29:36
  the most excited about where the field of astronomy
• 29:39
  in general is right now? So it's very exciting
• 29:42
  to have the James Webb out. I mean, since the
• 29:46
  launch three, four years ago, it's like revolutionizing
• 29:49
  astronomy. I think the next steps, we have the
• 29:52
  Vera Robin telescope in Chile, taking data as
• 29:57
  we speak. I think like the first three days they
• 30:00
  observe like 800 ,000 alerts of supernova explosions
• 30:04
  or something like that, which is insane. That
• 30:07
  means that we're going to have the next 10, 20
• 30:09
  years, we have more data that the whole astronomy
• 30:12
  have been taking in history. And that we have
• 30:16
  to deal with this data. How do we even analyze?
• 30:19
  tens of millions of galaxies. And moving forward,
• 30:23
  NASA is going to be launching a few space telescopes
• 30:28
  in the next few years. So you have the Roman
• 30:30
  Telescope, it's also doing a humongous survey,
• 30:33
  very deep observation, and you have to deal with
• 30:36
  the information of millions of galaxies. And
• 30:40
  now it's a combination of like, how do we use
• 30:43
  AI to deal with all this data? that we can trust
• 30:46
  the output of this data, but also what new science
• 30:50
  can we get from this, right? On the ground, we
• 30:54
  have Europe and US building the next generation
• 30:58
  of extremely large telescopes. These are 30 -meter
• 31:01
  telescopes in comparison with the 10 -meter.
• 31:03
  So for example, Europe, the European Southern...
• 31:08
  Observatory is building a 42 meter telescope
• 31:12
  in Chile. That's going to be first live, I think
• 31:15
  it's in six, five, six years each, something
• 31:18
  like that. So that's all new too. You want to
• 31:21
  have like new science. It's not about surveys,
• 31:24
  it's about detail. So they're like, if you want
• 31:27
  to know what is happening around the supermassive
• 31:30
  hole, you use that. If you want to know where
• 31:32
  the So the new James Webb telescope is observing
• 31:35
  galaxies in the elite universe. You go to the
• 31:37
  telescope and resolve it and see where the morphology
• 31:42
  of it. So it's just about the detail of observations
• 31:45
  of it. So I'm very excited for the next 10, 20
• 31:48
  years of using all this new telescope and see
• 31:51
  what we learn from them. So much data, we don't
• 31:54
  know what to do with it all. All the epic astronomy
• 31:58
  you're doing here, what still amazes you about
• 32:01
  astronomy? The pretty pictures. I'm very basic
• 32:05
  here. I was just like, show me a pretty picture.
• 32:07
  I was like, oh my God, this is so great. For
• 32:09
  my research, it's just have a new instrument
• 32:13
  in a new telescope and get the first light, the
• 32:16
  first image, which just excites me like it's
• 32:19
  no tomorrow. And then it really excites me to
• 32:21
  know I have a piece of knowledge of the universe
• 32:24
  that I'm the first person to have it in front
• 32:26
  of me and I need to figure it out. And this light
• 32:30
  just, I can stay. thinking about this for months.
• 32:36
  I'd like to thank Professor Rodriguez for coming
• 32:38
  on the show and being so generous with his time.
• 32:41
  What struck me in that conversation is just how
• 32:44
  much of the universe is hidden from us. It's
• 32:47
  remarkable to think that something as small as
• 32:49
  a dust grain containing tiny amounts of iron
• 32:52
  can act as a kind of compass. revealing the structure
• 32:56
  of these unseen forces that are shaping structures
• 32:59
  as enormous as galaxies. With research led by
• 33:04
  scientists like Professor Rodriguez, we're slowly
• 33:07
  piecing together a universe that's far more dynamic
• 33:11
  and far more interconnected than it first appears.
• 33:15
  If you'd like to learn more about his research
• 33:17
  and see the images we discussed in this episode,
• 33:20
  I'll leave a link in the show notes. After a
• 33:39
  quick break, we'll be back with a look at something
• 33:42
  closer to home, this week's night sky. Stay with
• 33:45
  us. Welcome back. As we close out the month of
• 34:01
  April and step into early May, the night sky
• 34:04
  offers a gentle transition from darker, moonless
• 34:08
  evenings earlier in the month to a bright and
• 34:11
  beautiful full moon rising at the end of the
• 34:13
  week. Throughout this week, the moon is in its
• 34:17
  waxing phase, growing brighter with each passing
• 34:20
  night. Early on, you'll find it as a waxing gibbous
• 34:24
  rising in the afternoon and shining well into
• 34:26
  the evening hours. But by Friday, May 1st, the
• 34:30
  moon reaches its full phase. This is the Flower
• 34:35
  Moon, a name that comes from the abundance of
• 34:38
  blooming plants this time of year. And while
• 34:41
  every full moon is worth a look, this one is
• 34:43
  what astronomers call a Micro Moon, meaning it's
• 34:47
  a bit farther from Earth than usual and may appear
• 34:50
  just slightly smaller in the sky. Earlier in
• 34:53
  the week, before the moon becomes fully illuminated,
• 34:56
  take a moment to look along the line between
• 34:58
  light and shadow, the lunar terminator. That's
• 35:02
  where craters and mountains stand out in sharp
• 35:05
  relief, offering some of the most dramatic views
• 35:08
  you can get through a small telescope. Now, turning
• 35:12
  to the planets. This is something of a split
• 35:15
  -sky week, with the brightest worlds divided
• 35:18
  between evening and morning. Just after sunset,
• 35:21
  look toward the western horizon and you'll immediately
• 35:24
  notice Venus. Brilliant and unmistakable, shining
• 35:29
  like a beacon in the twilight. Higher up, Jupiter
• 35:32
  continues to dominate the evening sky, steady
• 35:35
  and bright, and still one of the most rewarding
• 35:38
  objects to observe through a telescope. If you
• 35:41
  happen to be out before sunrise, there's more
• 35:44
  to see. Low in the eastern sky, Mercury, Mars,
• 35:48
  and Saturn form a loose grouping near the horizon.
• 35:52
  They're not especially bright right now, and
• 35:54
  you'll need a clear view to the east, but if
• 35:57
  you catch them, you're seeing the tail end of
• 35:59
  a quiet planetary gathering that's been unfolding
• 36:02
  over the past few weeks. Now, this time of year
• 36:06
  also brings something special for deep sky observers.
• 36:10
  We're in the midst of what astronomers call galaxy
• 36:13
  season. The familiar constellations of winter
• 36:16
  are slipping away, and in their place the sky
• 36:19
  is opening up to regions rich with distant galaxies,
• 36:24
  particularly in the constellations of Leo, Virgo,
• 36:27
  and Coma Berenices. Leo is easy to spot, high
• 36:31
  in the sky after sunset, marked by a distinctive
• 36:35
  backwards question mark shape. Just beyond it
• 36:38
  lies Virgo, a sprawling constellation that contains
• 36:42
  an entire cluster of galaxies some 50 million
• 36:46
  light years away. With a telescope and especially
• 36:50
  under darker skies, you can begin to pick out
• 36:53
  faint smudges of light. One particularly beautiful
• 36:56
  region is known as Markarian's Chain, a gentle
• 37:00
  arc of galaxies stretching across space, visible
• 37:04
  as a delicate pattern when conditions are right.
• 37:07
  And, if you're just using binoculars, don't miss
• 37:10
  the Beehive Cluster in Cancer. It's still visible
• 37:14
  early in the evening and remains one of the most
• 37:17
  rewarding open clusters in the sky. By the end
• 37:20
  of the week, the full moon takes over, brightening
• 37:23
  the sky and shifting our attention closer to
• 37:26
  home. That's going to do it for this week. If
• 37:33
  you found this episode interesting, please share
• 37:35
  it with a friend who might enjoy it. The easiest
• 37:38
  way to do that is by sending folks to our website,
• 37:42
  StarTrails .Show. And if you'd like to support
• 37:45
  the show, use the link on the site to buy me
• 37:48
  a coffee. It really helps. Be sure to follow
• 37:51
  Star Trails on Blue Sky and YouTube. Links are
• 37:55
  in the show notes. Until we meet again beneath
• 37:58
  the stars, Clear skies everyone!