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Brendan: Welcome to the 2024 season of the Astrophiz Podcasts.
My title is Brendan O ‘Brien and first of all, we would like to acknowledge Australia’s first astronomers, the Aboriginal and Torres Strait Islander individuals, the conventional homeowners and custodians of the land we are on.
This episode is produced on Yorta Yorta Nation,
… and we’d additionally like you to affect your native politicians to do extra to mitigate local weather change by shifting from fossil fuels to renewable vitality sources.
We’re now in our ninth 12 months of manufacturing with over 180 fabulous interviews with prime scientists from all over the world. Every month we produce two fabulous episodes: On the first of every month, Dr Ian AstroBlog Musgrave offers us his month-to-month sky information, plus a distinctive astrophotography problem. Then on the fifteenth of every month, we publish an interview with a main astronomer, astrophysicist, house scientist, information scientist, telescope engineer, mission supervisor or particle physicist, and we uncover their science journey and uncommon insights into how they suppose and conduct their superb analysis into precisely how our universe works.
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As we speak we have a sensational interview for you from Denmark with Dr. Hannah Diamond Lowe, who makes use of the world’s latest and most highly effective devices to probe the atmospheres of distant alien planets.
You’ll love her tales.
Brendan: Hey, Hannah.
Hannah: Hey, Brendan.
Brendan: As we speak, listeners, we’re zooming over 10 timezones to chilly Denmark for some slicing -edge science, and you’re invited to a very particular dialog. So as we speak, I’m fortunate sufficient to introduce you to Dr. Hannah Diamond -Lowe, who is a senior researcher in the exoplanet group on the
Technical College of Denmark, the place her groundbreaking analysis characterizes small exoplanet atmospheres utilizing floor and house -based observatories.
She is additionally the principal investigator of the Sizzling Rocks Survey, a giant observing program utilizing the now legendary James Webb House Telescope to take a look at terrestrial rocky exoplanets for their atmospheres as they orbit close by M-dwarf stars, as nicely as …. she’s received a companion program referred to as Sizzling Rock Stars which will measure the UV output of the M dwarf hosts with Hubble information.
These are the finest tasks names I’ve ever heard, Hannah. So thanks very a lot for talking with us as we speak.
Hannah: Oh, thank you so a lot for having me. It’s enjoyable to be right here.
Brendan: Okay, thanks. So earlier than we speak about your present exoplanet work, can you inform us the place you grew up, please, Hannah? And might you inform us how you first grew to become in science and house?
Hannah: Yeah, undoubtedly. So I am born and raised in New Jersey, East Coast of the United States. And I’m type of from the center of the state in a city referred to as Highland Park. So the space is a type of type of like dense suburbia. So I’m not truly one of these astronomers who did a lot of gazing up at the sky since there’s a good bit of mild air pollution.
I didn’t actually get into science and house till type of later in my education, however my dad has truly has all the time been fairly in astronomy. So like for Hanukkah, one 12 months I received a telescope and we would type of look at the moon and Saturn and I was into that for a whereas and then type of dropped it. However I suppose he was type of laying the groundwork for some astronomy later on.
Brendan: Okay. And what about these early college days and your earliest ambitions? And did your early ambitions change and evolve over time Hannah?
Hannah: Sure, there was a lot of adjustments in evolution. So yeah, as I talked about, there was like a small section of my childhood of wanting to be an astronomer, however… However there was additionally I wished to be an archaeologist, a political scientist, I suppose at one level a librarian was excessive on the listing. So I actually type of jumped round a lot.
However I suppose like usually, I simply all the time favored college and studying. And my favourite topics had been simply the ones the place I actually favored the academics. So at completely different factors, I actually favored English, math, historical past.
And even all by means of excessive college, I type of went again and forth and I was like, “Oh, I’m going to go again and jumped round a bit. However I didn’t get into truly type of focusing on science till I went for my undergraduate diploma at the College of Chicago.
In the US, we do this liberal arts schooling. So you have to take like a broad vary of topics, every little thing from math and science to historical past and literature. And then you select one thing to main in and type of research extra in depth. So I went into faculty type of pondering about possibly like I’d focus in anthropology or possibly linguistics, however undoubtedly I was pondering one thing in the humanities.
So at the finish of my first 12 months, I determined to do this research overseas program. And whereas I was learning overseas, I might take a course in astrophysics for non majors. So I might get my type of compulsory science credit score out of the manner and I received to spend a quarter in Paris. So Paris was nice, however I additionally actually, actually loved the non -major astrophysics course.
So after that, I type of determined to begin shifting extra over into the sciences. However I didn’t truly main in physics ’trigger at that level, there wasn’t sufficient time for me to graduate in time and take off the physics necessities … plus it was like ‘a lot’ of physics.!
So I truly majored in geophysical sciences, so I might take type of a extra numerous vary of science programs. So I took geology, biology, biodiversity, however I did take a lot of type of necessities in the physics division and in the astronomy division as nicely.
So yeah, then the relaxation is type of historical past.
I received extra and extra into analysis and astronomy and then type of that simply type of stored trending in that in that course ultimately.
Brendan: You should have had some inspiring academics and lecturers there?
Hannah: Completely!
Brendan: … and never solely did you get your first Bachelor’s science diploma in geophysical sciences, you did it with honours at the College of Chicago and then you went east to Harvard for your 5 12 months PhD in astronomy.
Now, for our early profession researchers … and we know we’ve received some listeners who are in that class. Might you inform us how you organized it and, firstly, why you made that huge transfer over to Europe to take up your first postdoc place at the Division of House Analysis and House Know-how at Danmarks Tekniske Universitet … the Technical College of Denmark. How and why did you do that, Hannah?
Hannah: Properly, firstly, glorious Danish pronunciation, I should say. Yeah, so there had been … there had been a lot of causes why that … some type of overlapping and some simply type of type of got here collectively. I suppose it would possibly be simpler first to reply extra the ‘How?’ since that was type of easy.
So, you know, in the final 12 months of a PhD, if you’re going to proceed in academia, that’s when you usually type of begin making use of for postdoc positions. And I was very not sure about type of the place I stood type of in contrast to different graduate college students.
So I utilized to a lot of postdoc positions. I suppose it was like 30. And I suppose that’s too many since a few of these I utilized to, you know, weren’t truly good matches for me.
However type of in the combine there was this place at DTU House, since they had been trying for somebody in exoplanet analysis that centered on small planets. So I, you know, I type of thought, “Okay, nicely, you know, throw that in the combine. “ So …so in all these purposes, however, however extra into the ‘Why?’ … I did have some concept that I wished to go to Europe for a postdoc.
I did a lot of my PhD in floor -based astronomy, and Europe has some of the finest floor -based telescopes and devices, however they’re additionally constructing the subsequent era of large floor -based telescopes. … And this is occurring in the US as nicely, however Europe is going to get there first. Yep, cool. Cool. So at the time I was making use of for a postdoc … this was the finish of 2019. … The launch of the James Webb House Telescope was supposed to occur at the starting of my PhD and had not occurred at all. So I was type of pondering … ‘Properly, I don’t need to rely on the House Telescope to launch if the timing is not going to work out for the three -year PhD.’
So I type of centered my postdoc purposes on floor -based analysis.
And that was, you know, a lot simpler to do for the kind of the European postdocs I utilized to. However I’ll be sincere, you know, one other motive was that I simply type of wished to have a change of tempo and have a completely different type of life expertise.
So I’m half British, and I grew up spending a lot of time in the UK. And I all the time had this type of curiosity of like, “Oh, possibly I might transfer to Europe at some level.“
However it didn’t occur for my PhD, clearly. So I thought, “Okay, possibly, possibly a postdoc was a good type of alternative to strive that. “ And actually, you know, I’ll be sincere, you know, even although I had a sturdy type of educational like pedigree, you know, College of Chicago and going to Harvard, I was actually burned out by the finish of my PhD. And I was not feeling very strongly about wanting to keep in academia.
I imply, I actually favored astronomy and I actually favored the questions, however the profession of an astronomer is not all the time simply getting to do the enjoyable sciencey components. So I thought, “Properly, if I’m not going to make it lengthy time period, I would possibly as nicely verify off some life objectives. “
And truly having that little bit of strain off type of being at possibly not type of the most prestigious place I might be at … and having a higher work -life steadiness actually led me again to having fun with extra truly going to work doing the type of nitty gritty stuff you have to do.
So I’m actually glad I ended up the place I did, however it was not such a clear path ahead all the time.
Brendan: Unbelievable. A nice mixture of strategic pondering … adventurism as nicely. As we’ll discover out a bit later, you landed in the good place for the analysis you’re doing at the second.
Okay, as we speak, the plan is to go again to the early exoplanet environment science, then have a fast look at your PhD, then hear about your newest discoveries and tasks.
However first, for our listeners, might we get the huge image? on exoplanet environment science, please, Hannah? What have been the huge milestones since 2001? It’s a science that’s been solely alive for 23 years., since a Hubble spectrum confirmed that sodium was current in the environment of HD 2094 58b.
Now, that’s fairly a mouthful! Simply earlier than you reply that query about the huge milestones, can you inform us, do you give nicknames to your goal exoplanets, Hannah?
Hannah: So I don’t usually give like nicknames for the planets, however the one you particularly simply talked about, HD 209458B. … that is one of the most well-known planets in exoplanet research.
So individuals have regarded at this for years and years and years. So that one, individuals will undoubtedly shorten to HD 209, or even simply 209 generally, which is take the first three numbers. However I’ll strive to keep away from throwing out too many planet numbers as a result of they can get a bit of a mouthful.
However if you do need a barely, type of, straightforward one, manner to suppose about them, as a result of it does type of appear a random assortment of letters and numbers, the HD half of HD 209 truly stands for Henry Draper, who was an astronomer in the 1800s who made this like catalog. And so this star was the 209 ,485th star in that catalog.
However Henry Draper in the 1800s would have had no concept that this specific star had a planet and that this would change into truly a well-known planet for exoplanet atmospheres.
Anyway, however sorry, again to the huge image. Yeah, in many methods we’re nonetheless type of portray the huge image of exoplanet atmospheres as a result of it’s, as you stated, simply such a younger subject.
However this was a main milestone. So in 2001, Sodium was detected in HD209 and I’s environment, and that paper was led by Dave Charbonneau . who was truly my PhD advisor. And yeah, shoulders of giants. Yeah, so this was a milestone, each for exoplanet science and additionally demonstrating the type of strategies we would use to pursue discoveries.
So this specific one was transmission. … transmission spectroscopy. I suppose you’ve had a few people on the podcast speak about transits. So transit is when a planet passes in entrance of its host star from our perspective.
And if you make the identical remark, however with a spectrograph that spreads out the incoming photons based mostly on their wavelength, you can then get a spectrum of the transit, or we would say a transmission spectrum. What that’s doing is that mild from the host star will filter by means of the planet’s environment on the manner to our telescopes, and any molecules current in the exoplanet’s environment will block mild at wavelengths particular to that molecule.
It’ll make the planet look bigger at these wavelengths, and in the end give us a spectral fingerprint of these molecules. So for a lengthy time, transmission spectroscopy was solely potential for scorching Jupiters, which are simply as they sound. They are planets the measurement and mass of Jupiter, however orbiting a lot, a lot nearer to their stars … truly nearer to their host stars than Mercury is to our personal solar. So very tight orbits. And these scorching Jupiters have prolonged puffy atmospheres that lend them themselves nicely to the approach of transmission spectroscopy.
So in this manner we’re detecting a host of molecules in scorching Jupiters, carbon dioxide, carbon monoxide in some instances, and we might type of try to decide possibly the place these planets fashioned in the disk as they migrated to their present place the place we see them now.
Brendan: Yep.
Hannah: So from there the remark strategies have expanded as nicely as the science.
So you can additionally take an emission spectrum, which is like a transmission spectrum, besides you watch as the planet passes behind its host star, and you strive to detect some thermal emissions, some photons from the infrared.
And we’ve additionally finished section curves. So that’s when you truly watch the complete orbit, and that offers you a wealth of info. And as these strategies have developed and we’ve constructed greater telescopes and extra steady and extra delicate devices, we’ve pushed to smaller and smaller planets. So a couple of key milestones had been detecting molecules in the atmospheres of sub -Neptunes, which are planets a little bit bigger and extra huge than the Earth, however additionally nonetheless comparatively puffy so we can nonetheless entry their atmospheres.
We’ve detected issues like water and methane in sub -Neptunes. And we’ve additionally detected flat featureless transmission spectra and we suppose this is the consequence of clouds or hazes in these planet atmospheres.
And I would say the final half of the huge image, which is very a lot nonetheless being painted, if you will, is like pushing down to even … even smaller planets, planets that are type of extra terrestrial in nature.
Brendan: – Unbelievable, that’s so cool. Okay, we’ve received the huge image there. We’re standing on the shoulders of giants. Now, can we have a fast look again at your PhD analysis to assist us perceive your private analysis trajectory?
You centered on the atmospheres of terrestrial exoplanets utilizing floor -based optical transits and the UV output of M dwarf host stars utilizing house -based UV spectra.
Now, what huge questions had been you asking and what issues had been you working on then that you had to overcome? overcome to get your PhD?
Hannah: Yeah, so that’s a nice query. So my PhD ended up type of having these two pillars, which was utilizing the floor -based telescopes to strive to observe terrestrial exoplanet atmospheres and then utilizing Hubble to strive to get UV spectra of their host stars.
The UV bit didn’t actually come until the finish of the PhDs, so I’ll deal with the first half, the floor -based telescopes, since I suppose I’ll speak a little bit extra about the UV bit later.
So I knew from the starting of grad college that I wished to do exoplanet analysis, and I had this undergraduate background in geophysical sciences. So I actually wished to be pondering about smaller, extra terrestrial, like, planets. The drawback was that I didn’t actually know what to do with the planets. … That was when I began graduate college, so this would have been the fall of 2015, there had been no terrestrial exoplanets that had been shut sufficient to us and additionally transiting so that we might truly research their atmospheres.
We detected lots with Kepler, however the Kepler terrestrial planets are too far away for us to do atmospheric comply with -up.
Brendan: – Yeah.
Hannah: However fortunately, in one of like very first conferences with my PhD advisor, he advised me that his former pupil, Zach Berta-Thompson, who’s now a professor at College of Colorado Boulder,.
Zach had simply found precisely this type of close by earth -sized planet transiting a close by star that we might truly look at for some atmospheric comply with -up. So principally as quickly as I received to Harvard, I utilized for time to use these telescopes that Harvard is a associate in referred to as the Magellan Telescopes.
These are six and a half meter twin telescopes at the Las Campanas Observatory in Chile. So I utilized for time to use a little spectrograph on one of these telescopes and I received it.
So I was ready to journey down the there and observe some of the type of early transits of this planet that had simply been found. So this planet was GJ 1132B.
Sorry, sorry for no enjoyable nickname. However I was ready to get a transmission spectrum of this close by planet. And it was fully flat. So not a lot of proof for an environment.
However given the telescope and instrument the place we had been solely actually delicate to comparatively puffy atmospheres. So the flat transmission spectrum was principally telling us that the planet was … we already knew the planet was comparable to the Earth in phrases of measurement and mass. It would possibly additionally be comparable to Earth in phrases of having a type of skinny environment tightly packed to the floor.
Or it might have been a naked rock or possibly have some bizarre excessive clouds. However this was principally the state of the artwork of what was potential at the time. So as a few extra type of terrestrial exoplanets received found that had been close by.
I would like go off down to Chile and strive to get observations with Magellan. And principally, I simply stored reporting flat traces for my complete PhD.
Brendan: Ouch!
Hannah: Yeah. However getting to journey to Chile and use these superb telescopes and be a half of that like observing neighborhood on the mountain was one of one of the actually type of nice treasures of my PhD expertise.
I completely beloved it. And then the aftermath of toiling away on analyzing this type of very noisy, floor -based information trying for tiny, tiny indicators that we had been, you know, be delicate to. That was robust. And particularly by your third or fourth flat line, it simply feels like you’re not actually doing that groundbreaking analysis you dream of when you go into a PhD.
So undoubtedly some highs and lows in that course of.
Brendan: I suppose it’s everybody’s dream to do some observations at Paranal.
Hannah: So this is truly not Paranal … that’s the mountain over. This is a smaller observatory, however it’s a very comparable location.
Brendan: Okay, so that brings us up to date.
Do you need to point out what would possibly be the very newest strategies and applied sciences that you’re utilizing to interrogate the atmospheres of exoplanets? You’ve hinted at them already.
What’s thrilling for exoplanet environment scientists proper now, Hannah?
Hannah: Yeah, I imply, I suppose 4 phrases, proper? James Webb House Telescope.
It’s actually simply opened so many doorways and given us entry to planets we haven’t been ready to research earlier than and additionally components of the type of. spectrum we haven’t had entry to or haven’t had entry to at the precision that James Webb can ship. I’ll strive to be like a little extra detailed about that. I’ll truly give an instance.
One of the early type of releases from JWST was a transmission spectrum of a type of scorching Jupiter we’d identified about for a lengthy time referred to as, right here comes one other boring title (laughs) WASP39B. And we had noticed this planet earlier than with Spitzer, which was a telescope that’s now been decommissioned.
However we had entry to these infrared channels, however they’re simply this huge type of photometric bucket. So you’re simply placing all your mild into this huge bucket. There’s not a lot of spectral info.
And simply from two huge mild buckets that Spitzer had, these two two photometric band passes, there had been hints of that possibly this planet had carbon dioxide.
However, you know, it was simply a trace that you can by no means inform something extra than that from Spitzer. We took one look with JWST. I suppose it was simply one transit. And you might simply see this lovely, clear function of carbon dioxide.
You know, you don’t want to go. and like dig into your fashions and do some fancy cross -correlation. It’s simply proper there. It’s simply obvious you in the face: Increase! Carbon Dioxide!
So that was lovely to see.! However even in this type of, you know, this was simply supposed to be a demonstration of what James Webb might do.
There was truly this second little bump type of proper subsequent to the huge CO2 function we had been seeing. And it was “Properly, what is this? “Like we weren’t anticipating this further little bump.
And what individuals suppose now is that this is truly the first detection of sulfur dioxide, SO2, in the environment of an exoplanet. And not solely is it, you know, it’s enjoyable to detect a new molecule, however what does that imply? And seeing this proof of photochemistry occurring in the environment of an exoplanet … which has by no means earlier than been, we’ve by no means seen proof of that earlier than, even although we type of suppose it ought to occur. So all that means is that sulfur dioxide is very simply damaged aside by excessive -energy photons coming from this planet’s host star.
So we shouldn’t actually be seeing it in the environment, however if we are seeing it, it means there should be a type of continuous cycle of the molecule being damaged, going by means of some chemical pathways, and then being reformed. This is a course of that occurs on Earth, it occurs on Venus. So, for instance, you know, we have oxygen in Earth’s environment. Photons from the Solar break aside that oxygen and permit ozone to type, which is of course very vital for us right here on Earth.
However simply that course of of photochemistry that is occurring, we’ve now additionally seen it occurring in an exoplanet. So this was simply type of like a thoughts -blowing bonus we had been not anticipating at all.
And I suppose type of all these early observations and in all probability for a lengthy time we are going to have these type of thrilling issues. You know, we’re going to look for one factor and finish up discovering one thing else or one thing we weren’t anticipating.
Brendan: Unbelievable.! And I requested you what’s thrilling and the timbre in your voice is conveying that pleasure very nicely. Okay, look, let’s do M-stars 101. And I did a search on the ArXiv server and discovered a paper you labored on which centered on M-stars. What are M-stars? M kind stars … and why are they the focus of your work ?
Hannah: Yeah … so going into exoplanet s … my PhD and exoplanets I did not suppose I would spend so a lot time with M stars however I’m so glad I did .
So an M star or we generally say an “M dwarf “ which simply means it’s nonetheless on the stellar primary sequence it’s a star like the solar is a star … it fuses hydrogen in its core, however it is smaller and much less huge. So M -dwarfs can be about 20% to 60 % the radius and mass of the solar … and they’re additionally usually a lot cooler. So the solar is round 5500 Kelvin and M -dwarfs will have a type of efficient temperature of round 3 ,000 Kelvin or a little bit cooler … a little bit hotter.
Brendan: – Yep,
Hannah: Okay. M-dwarfs have a few benefits if you’re in learning small planets and this is generally referred to as the ‘M-dwarf alternative.’
And these benefits are they, as I stated, are smaller. So if you’re trying for a transit, you’re trying for the relative measurement of the planet in contrast to the star.
If your star is smaller, that relative measurement of planet to star goes up in contrast to if you’re trying for a small planet round a a lot greater star. So that’s an benefit. M-Dwarfs are additionally a lot extra quite a few.
So our photo voltaic neighborhood is truly about 75 % M-Dwarfs. There’s not so many solar -like stars in contrast to M-Dwarfs. So you have extra alternatives to truly discover transiting planets and be ready to research them.
And lastly, as a result of M-Dwarfs are cooler, their “liveable zones” reside nearer in. So if you are in trying for temperate terrestrial planets and learning them, a type of temperate planet round an M-Dwarf would possibly be on an orbit of about 25 days. Now, that’s nonetheless fairly robust to observe … solely one alternative a month. However evaluate that to an Earth -like planet round a solar -like star in the liveable zone … that solely goes round as soon as a 12 months. So the 25 days truly appears a lot higher.
So this is why M-Dwarfs are targets if you are wanting to research terrestrial-like planets.
However they have a few drawbacks which have been actually enjoyable to study.
So an M -Dwarf is not simply a type of shrunken down solar. They truly have fairly completely different evolutionary histories. M -Dwarfs are lively for a lot longer time scales than a solar -like star. And they even in their type of center age on the primary sequence, they truly have very completely different trying spectral vitality distribution.
So in contrast to sun-like stars, M-Dwarfs emit a lot extra flux in the ultraviolet and excessive ultraviolet than their daylight counterparts. And that’s vital for my work … as a result of if you’re attempting to detect an environment round a terrestrial like planet, you are of course most delicate to the very outer areas of that environment, as a result of you know that will assist …. There’s extra probability for mild to cross by means of it.
However additionally these outer areas are extra inclined to a excessive vitality flux from the host M -dwarf star that … truly will get deposited in the higher atmospheric areas. So it doesn’t get down to the floor. It truly will get absorbed in the outer areas of a potential planet environment., so in case you don’t know what that star is depositing onto the exoplanet’s environment, you would possibly not actually perceive what you’re seeing, whether or not or not it is an environment with sure molecules. Perhaps the planet has no environment. You’re not going to get the full image except you perceive what the host M-dwarf is doing.
So that’s why I type of tried to deliver M-dwarfs into my analysis and tried to type of mix understanding M-dwarfs in the UV with attempting to characterize the atmospheres of terrestrial exoplanets.
Brendan: Unbelievable! That makes so a lot sense. Superior. (Hannah laughs) Okay, look thank you Hannah. Now there’s one other 15 papers you’ve labored on up on the ArXiv server and as you’ve talked about you’ve used information from Spitzer and Hubble.
You’ve additionally used the Chandra X -ray information to look at these scorching Jupiters and the scorching Neptunes and triple star techniques. You’ve been very busy … however your most latest work, clearly, as you’ve talked about, is all about rocky terrestrial exoplanets. Now, there’s two components to this subsequent query Hannah. …
Hannah: Okay…
Brendan: Are you trying particularly for Earth 2 .0 and for particular biosignatures?
And … this is a huge one. Might you inform us about your PI work and the Sizzling Rocks mission and how, not how, however securing remark time with the MIRI instrument on the JWST?
That is so cool. Now, Sizzling Rocks. appears each formidable and achievable and it sounds completely incredible. Your workforce should be over the moon with this one. (Hannah laughs)
What are they up to proper now? And when can we count on your atmospheric analyses of the targets you’ve chosen? When can we count on them to be revealed?
What’s the timeline Hannah?
Hannah: Yeah, okay. Massive query. To begin with the Earth 2 .0 query, I’m going to strive to make like a metaphor right here.
So I suppose that trying for Earth 2 .0 … you know, the course we’re shifting as a subject … to strive to look for Earth -like planets round solar -like stars and strive to decide if they have atmospheres or different properties comparable to our personal.
However simply as with buried treasure … it’d not be, you know, would possibly not finish up being every little thing you dreamed of … and all the gold and jewels, we additionally have to be conscious that what we would possibly not truly discover one thing that appears precisely like an Earth 2 .0.
And so we can both type of chill out about what we predict of as an Earth analog, however even extra importantly, again to my buried treasure metaphor, you know, isn’t it simply as a lot about the journey and the journey and, you know, the associates you make on the manner.
So on the manner we are literally growing the functionality to look for and detect an Earth 2 .0, we’re discovering so many unbelievable planets!
And we’re solely simply starting to be ready to characterize these atmospheres.
Brendan: Yep…
Hannah: So I don’t type of wake up each day pondering about Earth 2.0
Perhaps I would say I truly spend extra time pondering about Venus 2.0 … since usually the terrestrial planets we have entry to are hotter than the Earth.
Brendan: Yep …
Hannah: So it’s, I imply, for me, it’s extra about like there’s so a lot to study about exoplanets and so a lot simply to study about planets in common, populations, atmospheres, and pondering about the place our personal photo voltaic system matches into that is nonetheless a very open query.
We are able to nonetheless …. can possibly entry some type of Venus -like planets, hotter planets orbiting close to M -dwarf stars, however what about cooler planets? There’s planets out to the place possibly the place like Neptune is. What about the moons of these planets? So there’s so a lot type of discovery house that I suppose is price exploring. And if we if … we solely simply go strive to go straight for Earth 2.0 … we’re gonna miss a lot of actually attention-grabbing science that I suppose in the end will assist us extra to get there in the future.
Brendan: Yeah …
Hannah: So type of one of these adventures alongside the manner that I’m working in direction of is to ask whether or not or not terrestrial worlds round M -dwarfs can even have atmospheres at all.
So when I type of talked a little bit about M -dwarfs, they have these very completely different histories, they have a lot extra excessive vitality output, and this stuff can be damaging for exoplanet atmospheres.
So … So there’s been a type of, you know, this query for a lengthy time. Like, yeah, these stars current actually thrilling alternatives for detecting terrestrial exoplanets.
However does it cease there? Are these planets simply naked rocks? And if they are, that’s additionally attention-grabbing as a result of then you can research their surfaces and what these look like.
However in the Sizzling Rock Survey … we need to go after the low hanging fruit. So these are terrestrial worlds orbiting very shut to their M-Dwarf host stars and these M-Dwarfs are in flip shut to us so … so we get extra photons from them.
So this is vital as a result of even although I’ve talked a lot about transmission spectroscopy the Sizzling Rock Survey is doing like the reverse of that.
We’re going again to fundamentals. We are watching these planets in secondary eclipse, so when they cross behind their host stars, so like the reverse of the transit. And we’re utilizing the MIRI instrument the JWST as a photometer.
So as a huge photon bucket out at 15 microns, so nicely into the infrared. So we’re truly not getting spectra at all. We’re simply getting one huge information level out at 15 microns.
And we do this as a result of with the photon bucket you simply can accumulate many, many extra photons. And the secondary eclipse sign, so the type of, you know, you can suppose of the transit dip, it’s type of the identical factor in secondary eclipse, however a lot, a lot shallower. So you’re trying for this tiny sign, you want as many photons as you can get.
And the level of all of this is not so a lot to characterize an environment, however to ask whether or not or not an environment is even current on these planets.
So that’s the primary type of objective of the Sizzling Rock Survey. I will say to get the time to do this on James Webb is extremely aggressive and you want a lot of luck simply to get it additionally.
So it was a lot of onerous work by myself, my co -PI, Joao Mendonca, and additionally the complete workforce type of like pondering about this query early on. So it was a lot of work and a lot of luck to get that time.
And if you are out there and you have utilized for time on James Webb and like me been rejected many occasions, preserve attempting. It will occur at some level.
Yeah, so the place we are proper now with the survey is we’re simply at the starting. So we solely received our first remark at the finish of November. For the 9 planets in the survey, for most of them, we truly have to stack collectively a number of observations. So even although we received one remark, you know, we would possibly be ready for a second remark and the manner the James Webb scheduling works, you don’t have a lot management over that. So we don’t have any accomplished information units but, however we are at the moment in the information assortment section, and that is additionally coming with a lot of preliminary evaluation, and a lot of onerous work attempting to construct up these pipelines, these codes to analyze the information to be ready to do the finest we might do to strive to pull out this tiny, tiny sign. I am so, so fortunate to have a actually nice workforce of worldwide researchers who are actually excited about this work.
So as I stated, we have 9 planets in the survey and every planet has what we’re calling like a information set champion. So somebody who is accountable for getting that planet out to publication.
So they’ll do the lead evaluation and write the paper and this will type of be like their planet. And then there’s going to be tons and tons of future work to do and that’s going to of course type of be open to everybody. However I’m actually proud that all of our information set champions are early profession researchers, so they’re all both PhD college students or postdocs. And this is nice as a result of they have the time to actually dig into this information and get it to the place it wants to be. And of course I suppose it’s additionally vital to promote our college students and postdocs as they make their manner by means of the first levels of their careers. So yeah, the workforce is working onerous. We’re tremendous excited. We’re simply type of spinning up our type of bi -weekly conferences, attempting to evaluate pipeline outcomes. And, you know, a timeline is all the time robust. We’re hoping to get our first outcomes out by the summer time.
We gained’t have our first accomplished information set till the finish of this month. So even although we have made a few observations, we don’t have a accomplished information set on any one planet that we can begin pushing on.
So that’ll come in a couple of weeks although. Very thrilling time, however simply … simply at the starting. So I don’t have any like huge outcomes to share, however possibly I can give you a few hints.
Brendan: Unbelievable! That is so thrilling! And simply getting the time on the James Webb House Telescope is a enormous achievement in itself …
Hannah: (laughs)
Brendan: I can’t think about how aggressive it is. And look, simply a fast change of tempo right here. Right here’s a quote listeners from Hannah, which I know will astound some of you.
It’s thoughts -boggling, right here it is … quote. “There are extra planets than stars in the Milky Approach, and Earth -sized exoplanets are the most frequent.” Unquote. … Ha!
Hannah: (laughs)
Brendan: … Now w e know very nicely that science doesn’t all the time sail easily and we’re very blissful to put on our propeller heads. You’ve already challenged us fairly a bit. Might you share with us some particulars of a specific half of your small exoplanet atmospheric analysis that you’re working on proper now that’s driving you loopy or is astonishingly thrilling?
Or possibly it’s each, Hannah?
Hannah: Sure, so undoubtedly the most thrilling factor in my life proper now is the Sizzling Rocks Survey,
or I ought to say in my work life proper now is the Sizzling Rock Survey. And it is astonishingly thrilling and additionally driving me … loopy!
So it’s actually a combination of each. I suppose I’ve type of communicated a bit, you know, why it’s thrilling, the place we’re getting a first look at these planets, going to strive to perceive on a giant scale if these terrestrial worlds can even have atmospheres. However the piece that actually retains me up at night time is that the methodology we’re utilizing to do this, as I talked about, is, you know, the place the planets are passing ‘behind’ their host stars. And that means that the secondary eclipse sign has truly by no means been seen earlier than as a result of we’ve by no means had a telescope that might even detect it. And so what retains me up at night time is the idea of orbital eccentricity, which sounds tremendous boring, however it is actually terrifying.
Mainly, this is the concept that a easy mannequin of planets is that they’re on these completely round orbits, however there is truly normally some small quantity of eccentricity, and this was type of the factor that Kepler figured out again in the day … and the drawback is that if you have an orbit with sufficient eccentricity, then simply as a result of you see the transit doesn’t imply you truly know when the secondary eclipse is going to occur.
Brendan: Whoa!
Hannah: … and if you don’t know by a few seconds or a few minutes, okay, that’s tremendous. We all the time get time earlier than and after however if the eccentricity is excessive sufficient you might finish up being unsure by a few hours …
Brendan: Yep
Hannah: … and that is that’s too a lot … you can’t ask for you know tons and tons of time simply to possibly catch one thing or you can , however they want a a lot higher motive so a lot of work and a lot of you know emails to dynamicists and type of you know likelihood calculations went into attempting to make certain that we might truly catch these occasions.
Now, the enjoyable piece I’m going to share with you is we do have already from the program 4 secondary eclipse observations out of what will be a whole of 22.
And we suppose we are seeing the dip that we are trying for in all 4 of these observations. ..
Brendan: Good!
Hannah: … however we need to make actually, actually certain that we are not being tricked by possibly some noise, possibly an unfortunate systematic. So this means that we have to comb by means of all of the auxiliary information that James Webb collects whereas it observes and see if there’s something that would possibly be tricking us into pondering that this little dip is truly due to one thing else.
So, for instance, as JWST is settling into its life out in house, type of, it’s type of like a home that creaks a little bit.
So there’s these sudden, like they name them these “mirror tilt occasions” that have been noticed to occur. There’s nothing incorrect with the telescope, this is fully regular. However if one of these little mirror tilt occasion occurs, it simply type of creates a little shift, a little offset in your information
… and that’s tremendous. You can appropriate for it. And this one’s truly fairly straightforward. You can simply verify if that has occurred.
However if you don’t verify and one of these occurs, you would possibly suppose that there is an eclipse someplace the place there isn’t one, or possibly you would possibly suppose your eclipse is deeper than you suppose. And you’d have to be fairly unfortunate with the timing, however it’s actually not unimaginable.
So that’s a type of… of simpler one to verify for, however there’s many, many different little issues like, and, you know, in the end, we’re trying in this in the secondary eclipses … we’re trying for indicators at the degree of a few tens to a whole lot of components per million. So that is a dip. That is that sign is about 0 .01 p.c.
Brendan: Whoa!
Hannah: So it’s actually actually small. This is not one thing that was remotely potential earlier than JWST. So we’re already type of like pushing it to the limits of what we can detect. However it’s simply not an straightforward sign to pull out. James Webb can actually do it, however we’re not getting these like huge lovely transit indicators that possibly you noticed from like the … the huge press. releases from JWST. We’re trying for itty -bitty tiny indicators that we’re hoping are truly in the information.
So very thrilling … additionally very a lot driving me loopy.
Brendan: Wow, pushing the envelope.! Okay … Look, I’ve had a look at some of your revealed papers and I observed that you wrote a quantity of them when the code pandemic was at its peak again in 2021 and Denmark has been a success story in many methods with its “act quick and act with power coverage” … a bit like ours right here in Victoria.
Denmark got here by means of comparatively unscathed in contrast with some neighbouring and many comparatively sized nations. How did COVID have an effect on you and your household and what was the impression on your astrophysics analysis?
And what had been the classes that had been realized there?
Hannah: Yeah, I would say, you know, the, nicely, I’ll first to say, I was very lucky that my associates and household got here by means of COVID okay … and everybody’s tremendous and wholesome. I truly moved to Denmark in September 2020, so type of proper in the center of the pandemic, which was … you know, had like two masks on, you know, like barely consuming on the aircraft.
It was not the best transfer. However it was a lot extra managed right here in Denmark. There was a lot extra compliance with … you know, if there was a masks mandate in place, everybody wore their masks. When the vaccine grew to become accessible, everybody voluntarily received their vaccine and it meant that Denmark was ready to type of open up extra shortly and open up extra totally.
So, you know, even going again to the US type of some years later and there’s nonetheless type of half individuals are masking or there’s some small outbreaks … and Denmark was ready to, I suppose, fairly successfully type of lock down onerous however then open up a lot, a lot extra simply.
Now, this is a a lot smaller nation. And there’s a lot extra belief in authorities right here.
So that’s, that’s undoubtedly one thing they had been ready to do. However as far as it affected my analysis, you know, we had been type of inspired to restrict going into the workplace.
So I had to do a type of hybrid work from dwelling factor, which was a bit robust at first, as a result of I had no furnishings. So I would type of be like sitting on the ground …
Hannah & Brendan (each chortle)
Hannah: … you know, hooked into an Ethernet cable type of like typing away. However yeah, I fortunately had already had some analysis tasks that I was type of ending up for my thesis.
So yeah, it was undoubtedly robust to like type of begin collaborations right here, even with my coworkers, as a result of I wasn’t seeing them. And it’s, you know, it’s robust to type of meet individuals over Zoom and even harder to then type of have these conversations that can actually get a type of collaboration going. So I type of simply centered on ending up some work for my PhD.
And I would say I was fairly fortunate with I solely misplaced one potential transit remark due to COVID, as a consequence of a shutdown at the telescope. And in the better scheme of issues that’s manageable, the one type of, you know, the one upside to observational astronomy is … you know, … when a house telescope is taking your information, the house telescope can function even if you are not ready to go into your workplace. So, you know, as a result of I don’t have a lab, I was ready to preserve working.
And generally actually, simply being type of dwelling with nothing to do when nothing’s open, I was like, nicely, would possibly as nicely get some analysis finished. So it wasn’t too dangerous. … actually.
However I do suppose in phrases of … yeah … you requested about classes realized. I suppose everybody had a very completely different type of COVID expertise … and … it was undoubtedly a time of type of pondering a bit extra about my colleagues as type of human beings and their private lives … simply as a result of you’re zooming with individuals at dwelling and like … somebody’s child runs by.
And you know, it’s simply type of … it was having a bit extra type of compassion about … you know … “Oh this individual didn’t reply to my electronic mail” … and then you get on the zoom with them and it’s like their home is in chaos as a result of you know they’ve been working at dwelling and you know their partner and their children and their canine is you know barking and … it type of gave me like “Okay everybody right here is a individual let’s give some grace and give some give some time” … and I suppose a lot of individuals skilled that as nicely.
So I suppose it’s been in some methods optimistic for … for the subject and for type of educational life in common….
Brendan: Yeah, certainly. And look, whereas we’re on the matter of humanity,
Hannah: (laughs)
Brendan: ….and it’s a good segue right here, you’ve painted the huge image of exoplanet atmospheres … We’ve regarded at your early analysis and your most present work and we’ve gone all sciencey simply for a little whereas. However Hannah, would you like to inform us about some of the issues exterior your work at DTU house?
What brings you common … aaah … experiences of nice pleasure in your life?
Hannah: Pleasure? I strive to have a type of wealthy full life exterior of my work.
I suppose the work life steadiness is actually vital. And it’s been a nice type of life expertise to dwell in Denmark. I dwell in the capital metropolis of Copenhagen.
I dwell right here with my associate, so we dwell collectively right here from the U .S. So we’re all the time spending our weekends attempting to go someplace new in the metropolis.
There’s all the time type of artwork exhibits that are being put on, normally a live performance. you can see. There’s nice eating places, nice bars. So I actually like type of touring and exploring new locations.
So it’s been so a lot enjoyable to do that in … in a new nation. And it’s additionally been, you know, type of so a lot enjoyable to type of go round and see, you know, you can simply like take a prepare and be in a completely different nation in a completely different metropolis and coming from someplace like the U .S. that is. so thrilling and so novel. So that’s type of what a weekend will look like.
I actually like to camp and hike and go backpacking. So there’s been nice alternatives to do that. Not in Denmark, however in Norway and in Sweden, which are very close by.
So I’ve been taking a lot of benefit of that for type of a little longer, longer type of week trip. It’s been actually rewarding to to type of dwell someplace the place that’s anticipated and inspired to take that time to your self.
And so I’ve actually tried to take benefit of that and type of make certain I incorporate that, you know, for for the subsequent stage no matter I do subsequent, I need to make certain that I honor the life half of the work – life …
Brendan: Unbelievable. I’m having a bit of envy assault right here. Thank you. You’re educating, you’re mentoring graduates and undergraduates … aaah … you’re main your research teams, you’re a PI main an extremely proficient analysis workforce, and you have a lengthy historical past of giving invited talks to colleagues and open talks to the common public.
Is outreach an vital half of being an astrophysicist?
Hannah: Sure! I suppose it’s not simply an vital half, however type of an integral half to the job.
So what I do is primary analysis and most of my work is publicly funded by means of nationwide grants. And so that means that, to some diploma, taxpayer {dollars} go to make this analysis occur.
And that means that you have to give that again to the individuals. individuals and particularly if they’re simply to type of make that accessible. It took me type of a whereas to determine out what type of outreach I like to do.
I suppose a lot of individuals are actually excited about type of encouraging the subsequent era of scientists and I suppose that is extremely vital however I have actually by no means favored working with children and so I would type of do a couple of issues like that and simply be fully exhausted and not … not in a enjoyable manner.
And then in direction of the finish of graduate college, I signed up to be a half of this sequence referred to as the Beacon Hill lecture sequence. And it’s principally a set of programs that retired people can signal up for.
So these individuals are not essentially scientists or engineers or something like that in their skilled lives, however possibly have all the time had a private curiosity in astronomy. And now they’re retired, so they can, you know, take these lessons in the center of the day in Boston.
And so I gave an hour lecture on type of the subject of exoplanets.
And that was tremendous enjoyable! I beloved it!
I beloved getting questions from these, you know, actually individuals who, yeah, possibly they’re not going to have a second profession as an astronomer … however I suppose they are completely deserving of being reached out to … to type of clarify what’s occurring in the present subject of astronomy. So I’ve undoubtedly continued that.
There’s a comparable lecture sequence right here in Denmark referred to as the Folkeuniversitetet … So it’s like the Individuals’s College. So I have given lectures on exoplanets for a type of astronomy course that anybody in Denmark can signal up for. However once more, it’s normally usually like retired people trying to proceed studying and proceed being curious. And that’s been actually gratifying. So I’ve finished extra of that type of outreach after I figured out that … “Oh, I don’t have to go into elementary college school rooms.“
I can truly speak to type of the half of the inhabitants that I actually get pleasure from reaching out to.
And I suppose that’s simply ias useful …. since, you know, they’re the ones truly serving to to fund the analysis. And we ought to additionally focus on, you know, individuals at all levels of their lives attempting to study and being curious.
Brendan: Wonderful! Thank you very a lot, Hannah. Now, lastly, the mic is all yours. And you’ve received the alternative now to give us your favourite rant or rave about one of the challenges that we face in science … in fairness … in representations of range … or science denialism … I’ve received a lengthy listing right here … science profession paths … your personal ardour for analysis … or as you’ve hinted at earlier than … our human quest for new data. The microphone’s all yours, Hannah.
Hannah: Thank you. I suppose I talked about at the prime that I all the time had all these pursuits in college earlier than touchdown in astronomy and one of them is that I’ve all the time beloved to learn and I love literature and even a little bit of writing to some extent however principally studying and as I’ve gone additional and additional in astronomy I discover myself pondering extra and extra about type of narrative and tales and how truly simply as vital of science analysis is the communication of that analysis. And there are tales about our analysis, there’s tales about ourselves, and being type of conscious of the place you are in a story or how a story has fashioned about your analysis … about your profession. I suppose it’s one thing that’s been actually, nicely, I’ve actually discovered it highly effective to suppose about just lately. So I’ll give type of a few examples or I’ll give two examples:
For instance, you know, my profession … profession story modified a lot when I received this Sizzling Rocks program accepted to JWST … and … you know, it’s very good to preserve a optimistic perspective. And this is a actually nice story to inform … I studied these terrestrial exoplanets as a grad pupil and sort of struggled.
And then, you know, lastly made it to this … this huge program that’s going to reply some of these questions that I am genuinely excited about.
However what’s type of hidden in that story are a lot of rejections and a lot of setbacks and actually some wavering on whether or not or not I wished to proceed even working in astronomy or not.
And, you know, my story from like two years in the past was a little bit meandering, a little bit misplaced in a manner. And then all of the sudden this one type of fortunate factor occurs and that actually turns the complete factor round.
And … And I suppose it’s vital to type of be conscious of how that story is altering. One, as a result of it can be, you know, in one sense, like, you know, “Hold going … it can change.!”
… however one other to type of bear in mind that like, this was not, you know, predetermined this, that there was no type of regular march in direction of the place I am as we speak.
It was … there was a lot of uncertainty. And I suppose there was simply as good a probability. that my program wouldn’t be accepted. And possibly I would have stored going and possibly not … who is aware of? And that’s type of … you know … you have to type of take these issues that the universe type of throws at you.
Brendan: Yeah. …
Hannah: … however I suppose it’s additionally vital to understand that science is additionally about storytelling.
And I’ll give one final instance. This is type of about a paper I revealed in 2022 … and I will give a nickname to this system … it’s referred to as the K23 system, and it has three planets.
And I’ll name these the three bears.
And the first planet closest to the solar, this is like the huge bear.
It’s a sub -neptune. It’s bigger, extra huge than the Earth. It’s puffier. And then there’s type of type of additional out from that. There’s a barely smaller planet made possibly type of between a sub -Neptune and a rocky planet in phrases of measurement and mass.
And then additional out, simply kissing the liveable zone of this system was this little planet that we thought was terrestrial. You know … “Ooh, possibly this is the good planet for life!”
You know, proper in the Goldilocks zone, you know, Goldilocks and three bears. Okay, so when I was first trying at this system, I thought … “Okay, this is cool” … we have three planets … they’re round a frequent host star, so I can type of put all this information collectively, use our fashions of atmospheric mass loss and evolution, and simply type of clarify the story that I was clearly seeing with these three planets … with one possibly completely in the liveable zone.
However whereas I was placing collectively the observations and fashions from my colleagues and type of digging into the literature, the… it wasn’t … the story was not becoming collectively.
They’re stored being these items that didn’t make sense. As an alternative of simply ignoring these, I type of tried to deliver these in and see what was occurring. And what I ended up with is truly a very completely different story … the place it truly appears that possibly these planets fashioned farther out than we at the moment see them and migrated inwards, which means that that outer planet that I thought was my … you know, … “simply proper rocky planet in the liveable zone” … I’m now pondering truly it’s simply a type of a lot smaller model of a sub -Neptune, one thing that has a puffier environment than we count on.
And the finest half of this story is that it wants an epilogue. So now there’s extra work to do to strive to take a look at that speculation, see what’s truly going on. However, you know, simply like with this system and with type of our lives actually … and something that occurs … simply type of studying by means of that scientific course of to be open to possibly the story is not going the manner you suppose it’s gonna go.
And that doesn’t imply it has to be worse. It simply means it has to be … it can be completely different and type of being open to that and open to a possibly even extra thrilling final result …
I suppose is actually vital in science and, you know, our careers and additionally in life.
That’s what I’ve been pondering about just lately.
Brendan: Unbelievable and you are certainly a storyteller.
You’ve mixed artwork, science, literature and storytelling all in one right here for the final hour with us Hannah …. Look … simply earlier than we go, is there something else we ought to watch out for in the close to future? What are you maintaining your eye on?
Hannah: Yeah … so please keep tuned for outcomes from the Sizzling Rock Survey!
… however I additionally suppose there’s a lot of actually attention-grabbing analysis. You know, undoubtedly something for exoplanets coming out of James Webb is going to be actually thrilling … however … I additionally simply need to make a fast plug to … don’t lose religion in your floor -based telescopes.
There is so a lot attention-grabbing work coming out of floor -based telescopes from excessive -resolution spectrographs. This is a complete different type of approach for attempting to detect atmospheres that I didn’t even get a probability to speak about.
However we are attempting to construct these subsequent -generation floor -based telescopes. And these actually are not, they’re not competing with JWST … they’re actually complementary and actually needed.
There’s some issues that you can do from the floor, make these very, very technically type of finicky devices that you want to continuously tune that you simply can’t do from house.
And so I don’t need individuals to suppose that, oh, simply ’trigger we’ve put up James Webb, we can neglect about all these superb floor -based telescopes that individuals work on, keep, and they are nonetheless producing actually thrilling science.
So I would say don’t lose religion in your floor -based observations.
Brendan: Unbelievable, and there’s some superb devices being constructed as we converse. Okay … nicely, thank you so a lot, Dr. Hannah Diamond-Lowe, on behalf of all of our listeners, and particularly from me, been actually thrilling to be talking with you … manner over there in Denmark … chilly as it is and scorching as it is right here.
Hannah: (laughs)
Brendan: Thank you particularly for your time in your superb schedule and the pressures to analyze all that lovely Sizzling Rocks information that the JWST is going to be or is and will be beaming down to you.
And good luck with your subsequent adventures, your analysis, your great weekends that you’ll have. and all your future travels, and our listeners can tune in to the work that the Exoplanets Group do.
They can see the individuals and their analysis. It’s all at Exoplanets–DOT-dk.
Could your profession proceed to be out of this world! Thank you, Hannah!
Hannah: Oh, thank you so a lot. This is so a lot enjoyable!
Brendan: Wonderful.
Hannah: Bye bye.!
Brendan: And bear in mind Astrophiz is free and unsponsored … however we all the time advocate that you verify out Dr Ian Musgrave’s AstroBlogger web site to discover out what’s up in the night time sky.
See you in two weeks. Hold trying up!
