See our second event from 6 August 2020 when we learned about the hunt for exoplanets and SETI from Sabine Graf!!
Summary:
Since the beginning of human cultures people wonder about other worlds. In this talk we learn about the different exoplanets discovered since 1995. The wide impact of that discovery on science was honoured 2019 with the Nobel prize for Physics for the two discoverers. We also learn about the methods of detecting exoplanets and the difficulties of finding a second earth. Towards the end we will take a look on the search for extraterrestrial life.
For more information on the Schnupper Praktikum offered by Sabine to students in the Köln region, go to physik.uni-koeln.de/schnupperpraktikum.html
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Planets and life beyond the earth following by an up-to-date astronomical press release before starting just a piece of information and also an announcement um you may already know but it’s worse to tell that we have planned our uh live streaming program every first thursday of months 7 p.m central european
Time you have asked us how uh it’s possible to be informed of the events that’s prettiest for straightforward you can follow us on facebook or instagram page with the name aotcon and we also keep posting the advertisement of the event on the facebook page of university of cologne
And good news is that we have already set up our next event and we are happy to inform you that this there at on third of september at 7 00 pm we are hosting professor kramer from university of bonn with an interesting talk about pulsars okay make sure you are comfortable
And you have your drink lean back and enjoy without further delay let’s welcome our today’s speaker and after a short introduction about what she is doing jump into the first part of today’s event welcome zabina and thanks for accepting our invitation thanks for having me okay i will give a
Short introduction about what you are doing and then you can start zabina is a third year phd candidate in astrophysics here in university of cologne she did also have bachelor and masters studies in physics in cologne her phd research is dedicated to simulation of planet formation however
As a side project she’s involved in testing calibration unit of metis instrument metis is going to be an imager and a spectrograph under novel infrared telescope elt stands for extremely large telescope in chile and it is going to get the first light in 2025 it’s also worth to mention that zabina is
Interested in involving school students in small exp a small experimental physics project to give them a taste of physicists the real life therefore she is moderating a program called ischnu palpa practicum to ask neighboring school students in a one day program in the university if you are interested
On that you can find more information on the address in the comments below this video good i believe uh that life beyond the earth is of the most absorbing topics in the astronomy saving we are looking forward to your talk please take over and go ahead thank you
I need to share my street screen yes sir so i hope everyone can see it you are good yeah perfect thank you very much boya for this very nice interjection and um i’m very happy to talk um about exoplanets and the search for extraterrestrial life an exoplanet which is a extrasolar planet
Which means the planet is outside of the solar system and it circles around another star since the beginning of human cultures people wonder about other worlds in this talk we learn about the different exoplanets discovered since 1995 and the first exoplanet was around the sundance star was pegasi 51 pikacy b
The star is 40 light years away and the planet has an evolution it circles around this its main star in 4.2 days which are 100 hours and the planet which was discovered is uh half the size roughly half the size of jupiter so it was it is totally different uh than
The planets we know in our solar systems we will talk about that later on so most of you have probably seen planets pictures of exoplanets most of them like my first slide our artist impression how the arches think exoplanet will look like but i can only show you
Very few pictures of exoplanets which are done by telescopes because they are so rare these two were one of the firsts made in 2008 and now we look at this system a little closer on the right system here we see the planet formal formal how b this
This is a little zoom on the planet which is in here the the planet um circles around the star uh in about six times of the distance of pluto and the sun so it is quite far away it’s 113 astronomical units which means and one astronomical unit is the distance
Earth’s sun so it is quite far away and the planet has roughly three jupiter masses and here we see the pictures of hubble it’s a it’s the space telescope and it was followed by the movement of the planet over several years um but we don’t know exactly how
We don’t know exactly how long it takes to go one time around the sun but we can guess it’s it has to be at least several hundred years um it was uh the direct um it was one of the most famous pictures uh during that time and it was published 2008.
Um the star form for malhot is at a distance of 25 light years and it has roughly um the mass double the mass of the sun and now we want to look at this picture a little bit More closely it is in the middle you have to to make the star a little bit to cover the start that we can actually picture the dust and the planets around that star because um the dust and the planet don’t emit light they just reflect light and otherwise if we
Don’t um shade the star um the light would be so the star would just over um we couldn’t see anything of the planet that’s why we have to cover um the central star to see the planets yeah the same method was also used for the left picture this
Here we see the star hr 8799 and it was observed 2008 uh with the gemini north observatory and the keg observatory and they actually were able to observe a whole planetary system and this planetary system is roughly 130 light years away from us and thanks to adaptive optics
It was possible to show the four planets yeah the star is one and a half times the mass of the sun and it was also published yes and it’s an infrared image and here in the middle you also see that the star is covered yeah like you have seen
They are different the exoplanets which were discovered or pictured are quite different to this system we know so but nevertheless what we do what the scientists did was to project what we know about our solar system onto the exoplanets they found the system is not internationally binding but um it is
Mostly used so for example we have two types of planets with terrestrial planets these are rocky planets like the earth’s mass mekkor and venus and the jovanian planets they are gaseous planets big planets like um neptune saturn jupiter and uranus and um but um because of the different things
We found because the location not only the size and the mass is important but also the location uh in respect to the sun is very important that’s why there is a further classification that you also say where it’s located that’s why for example you call them a hot jupiter because it’s a jupiter-sized
Planet but it is close to the star that but it would be a hot jupiter this would um be like um the name for the planet which was discovered in 1995 and for example um the planet uh former howard bay it would be called a cold jupiter because it’s far away
So um here we can see that a little bit more detail here we see the terrence group and then the giant group and here we see the different zones hot zone habitable zone and cold zone and here is the earth located it’s a earth because it’s a
So every planet which would be roughly the size of earth would be located here and um also within the uh distance uh which i have which is warm would be here but we also see that there are a lot of hot and big planets very close to the star which
Is not visible in our solar system as we know the bigger planets are outside we will talk about that later too and also you see there are some bigger cold planets um further outside found but there are only very few small macra resize planets found this has something to do with the
Observational bias we have we will talk about how we find exoplanets and that will explain the gap of observation um unlike the um uss enterprise from star trek we cannot fly to the exoplanet and scan the planet and figure out what the atmosphere looks like the size
And if there is life yeah we don’t have it that easy we have only this view we can look in our night sky and we see the milky way and the stars close to our area that’s why we can use the maybe almost obvious method it’s the direct method but it’s also
The most difficult method because you need very good instruments which are able to see those exoplanets as the planets are just reflecting the light and don’t shine by this themselves so um it is a very difficult task and we will talk about a telescope which we can do that later
It’s for example the elt you already heard of the indirect methods are much more successful because you can detect exoplanets which much smaller telescopes when i was in in 12th grade um from for one of the school works i was doing i was observing an exoplanet by myself
With this only 30 centimeter telescope at the max planck institute in heidelberg for astronomy in heidelberg and this is the reason why indirect methods um yeah you can also observe um what i observed was a hot jupiter because it’s much easier because um the undirect methods use the fact of for
Example the one which um several methods use the fact that planets have a bigger mass or are just bigger and the probability of passing through is higher and then they interfere with the mass they interfere with the planet with a star and they wobble or other things so we look a little bit
Closer to the to the method because for example this micro mazing micro microlensing yet the the mass of the planet influences um the the light curve which is coming from the star behind the bad thing about this method is you can only do it once because it’s a random event
It’s like a planetary system this one this is a planet um just a passes of a star in the background and um by chance it was detected um but there are also other metals like as dominant astrometry they use this method which i told you about the mass interference like um
The the mass of the planet and the star interacting with each other so um the star um starts to wobble so we look we look at the system from the top so we see actually the movement of the star but we can also use the same effect for the radial velocity so we
Look from the side on the system and the star and the planet moves like this and here we see that the light shifted from red to blue and there is another method where it’s also good to have a big planet is the trenches method um the planet passes in front of the
Sun and um it uh there’s a the light is is blocked by the planet and this makes a dip in the curve and we will take now a look at the transit mode method a little more for example we know this method from our own solar system
If venus or macro is passing in front of the sun we can see it actually the smaller the harder it is to detect it because the dip becomes much smaller we can see for example if an alien observer of our sun would look at our system and then
The earth would only make a dip of the um of the lightness of the sun just by 0.01 percent and the jupiter would uh already make a dip of one percent it’s a quite easy calculation you just look at the different here i showed you the calculation it’s quite easy you just
Have to um put the radii squared into um in respect to each other and um but to to do that um but we don’t want to find hot jupiters because um we were going to look for life on different um planets so we want to look for earth-like planets
Because we know on earth life was happening so we need very good telescopes like the space telescope kepler which can observe those dip from very faint from fair very faint telescopes so but we need we need to remember that the more the smaller the planet the better needs the telescope to be and
That’s also um true for the probability of happening it’s very difficult the probability of um transiting is higher the closer the planet is and uh the further away the planet the probability of passing through um the sideline of sight it’s it’s smaller that’s why um yeah the more
Hot jupiters more big close planets were detected than um the smaller earth-sized planets at a further distance but the the advantage of such a transit method is that you can also tell something about the atmosphere because the star rays passes through the atmosphere of the planet and rays interact with the gas
And with those absorption lines we can make conclusion um about the elements in the atmosphere and those but those absorption lines are also very very small that’s why you need really good telescopes to measure them and of course the bigger the planet the more you can see
And the smaller the planet the harder is to analyze the atmosphere that’s why this is something very new and we will talk about a telescope which will be able to do that as soon um yeah i already talked about the nasa kepler mission and we see that
In to uh that this planet uh that this mission really um detected a majority of the known um exoplanets and now we come to the e-elt it’s a european um extremely large telescope and it will like mention before have the first slide in 2025 and uh they are the goals to
Re-observe the exoplanets and make direct imaging and also then um analyzing the atmosphere of those planets and with thyroid imaging we have the advantage that we can image the planets which are not too close to the star but relatively small so um earth-like that that is the goal and this
Instrument will work in the mid-infrared range to detect oxygen and ozone and they are the university of cologne participates in developing the instrument mates which is on that telescope and there we will build a small part the warm calibration unit here and now we talk about this this bias of observation
While looking at the time scale of detection of those different planets here we see that in the early phase in the early phase bigger planets have been discovered and then with kepler um also through those um observational bias we also see that a lot of big planets very close to the stars have
Been discovered with kepler and now we come a little bit closer to my topic already in science fiction um a planet with two sons um where was um known let’s say the luke skywalker’s home planet tattoo in this uh in star wars was cycling around two sons in 1972 in 1977
And the first real exoplanet in a binary system was discovered in 2011 this is not long ago and it was kepler 16b and this was a gas giant similar size of saturn and um there are two different kinds of exoplanets in binary systems the one we know from star wars
Like the planet circling both stars like the earth circles the sun but just around two stars and we have a second type it’s called satellite s-type um the planet circles just one star and the binary circle each other yeah so there are different um systems and now it’s really interesting how um they
Are stable how do the planet form there and how do they reach the position and um yeah it’s it’s up to date science as uh the first uh planet was discovered uh 2011 so um there is a lot of um science going on and a lot of things happening right now
Um my um work is i simulate the system kepler 38 it’s also a binary system it is very tight those stars it’s only 0.4 you like um separation between the binary stars and the cinema major axis of the planet it’s 0.5 au so it’s roughly half the size of earth
Uh earth’s sun distance and but it’s a giant planet it’s a neptune-sized planet so um we don’t uh there are two different scenarios of how those planets could form one of them is that it formed further outside like the big gaseous planets we have in our solar system
But migrated inwards and this is um we we need to understand better and we do simulations and to know this the process to get to know the physical process behind it uh because we cannot observe that process because of the time scales we have uh we only have uh the one lifetime to
Observe and uh this planets it takes much more time to form a soul star in the planets and stuff that’s why we need to do simulations um yeah so here in the simulation the planet starts further outside and then migrates inwards and but how yoda would say a lot to learn you still
Have so there is a lot of things we all need to learn and there are new discoveries um yeah every day so it’s it’s quite cool so now uh we can go uh continue for the search uh for life um we we want to know if there is extra
Rest your life outside which we can see and uh we will also talk about what is needed for life to um um to to be and um yeah and how could they look how could that life look like and here we found it already this is like an artist’s impression
Of a binary system and this aliens or visitors on it or maybe we find a green guy um now we take a a closer look on what is necessary for life um first we need most famous is for example the word habitat zone i think everyone heard which read about
External extraterrestrial life heard about the habitable zone this is just a phrase for that it the planet could have liquid water because of the distance around the star every star has a different distance where this zone is possible here we see for example a sun-like star the habitus zone
Is further out and the smaller star has the habitat zone closer in and there are different aspects which which are important for example that um the lifetime of the star needs to be long enough for life to develop so a big giant star which has burns all the fuels within
Like 10 million years uh it’s it’s not a good candidate for life because um this the area that the life times are just too small that’s why we want to look to earth-like stars sun-like stars or smaller stars because the sun has a lifetime of 10 billion years
And earth is already 4.5 billion years old so there it needs some time for life to develop um now someone would guess oh yeah then let’s search for a small smaller stars than the sun then the the star lives longer than the sun and the life has more has
Much more to the chance to develop to see something but um there is a catch for example with klisi 581 it is 20 light years this distance and it has a planet d which was suspected to be in the habitable zone and it’s a super earth so it’s a slightly
Slightly heavier than the earth but there is a there is a problem it’s called um connected rotation and we know this connected rotation from the moon the moon is circling the earth and it’s always showing us the same side so we only see one side of the moon
And this connected rotation leads to uh if the planet rotates around a star that one side of the planet it’s really really hot in the other side of the planet it’s cold so if that planet has an atmosphere that would suggest that there would be strong winds to um
To to even out the temperature diff differential so this is not this is not a good place for life to develop because the atmosphere is very turbulent and with strong winds that’s why most of the surveys now go back to search for sun-like stars and planets around them but there are further
Factors for life for example the stability of the rotation for example we have the moon so our planet rotates stable around itself we don’t have a planet wobbling around and this this really leads to a stable climate which is needed for life to develop um also we need a cosmic cleaner
Like the jupiter we have a big giant planet in our solar system which attracts all those comets or asteroids um which come into our solar system and then um diverts them or make them crush into it so we don’t get hit by um by metro metroids too often and
Uh another factor is the magnetic field this protects us from the cosmic rays which really can destroys the cells and also from the solar rays when they when there is a solar storm so this is very important and um also which is very important is that we are in a
Relatively calm area which means there is no young star which is going to explode in a supernova soon and burst away our atmosphere or emits a very unhealthy race so this is a good spot that we are like in a calm and rather boring neighborhood in our galaxy yeah this is
These are just some of the um important factors which are needed for for life to develop and like you see there are a lot of factors so it’s quite difficult um yeah to to find um then um life because if you look for a moon in a different
You first have a star which is far away and you’re so happy that you can detect the star or see it with direct imaging but a moon around this this exoplanet is a lot smaller and also just reflecting so this really will need um top-notch cutting-edge technology in telescopes
And this will there will be a lot of things happening the next few years and decades so a huge area that’s why also the nobel prize was given to two physicists who discovered the first exoplanets in 2019 to open up that interesting field of exploration of exoplanets
So but also since the beginning of human culture people were thinking about other worlds or other life so for example the philosophers was metro doors from chios in in the fourth century um um a uh before um christ um he was asking um could there be other worlds for example
Or um immanuel kant uh in from 724 he lived to 1804 and he uh has written a very famous um book aldemaine natural sister and there he states the assumption that all stars are sons which could inherit worlds so i i give you for everyone who speaks german too
Who want to read the original passage here is the original passage yeah and um and there is this one formula which is often um cited when there is a discussion about exoplanets and let’s say this has to be this equation is not 100 um scientific it’s more like
Something where you can think about the factors which are needed to that life is possible uh intelligent life is possible and i think it’s a it’s a it’s a nice thing to think about but it’s more it’s it’s not a scientific um so for example uh heath was thinking about the average
Star formation per year in our galaxy you have to take in account and then the share of the stars his planetary system and then the average number of planets per stars with the hub in the habitat zone and if you have a habited planet these planets not all of them
Have life and then not all of those planets have intelligence life so there’s also a fraction of that and from those fraction of intelligence life the life also want to have needs to have interest in interstellar communication that we can know about it and then we also have to take
Into account the lifetime of a technically developed civilization in years and then um there are different answers to this scientific in this not so very scientific equation some people say like for example in the star trek universe they would say 150 000 intelligence life forms the equation would be hundred and fifty thousand
Um yeah and uh other people say it’s just one and hopefully it’s us and uh yeah so so this is a very um it’s it’s it’s a nice thing to think about but uh yeah also um it’s very um very unlikely for us to communicate to another intelligence lifeform just because
Of the way um the distances we have because if something is 40 light years away a planet then it needs the signal needs 40 years to travel and 40 years back which is 80 years okay this could be possible but the conversation would be very um
Rare but it’s more like most more likely that the planet which inherits life would be much much further away maybe in a different galaxy which we cannot even detect with our technology today so and the next galaxy is andromeda with i don’t know a lot more like yes
So it it’s impossible to communicate nowadays maybe we don’t know what’s happening so i hope i uh inspired you a little bit to think about it and um yeah and hope you’re also excited about the new science which come up the new discoveries which pop up
And yeah and take a look into that thank you very much and also thank you you for hosting me today oh yeah ah yeah thank you very much it was really fascinating um actually i was also thinking about the last equation non-scientific equation that you shared with us
Um i was thinking that you know all these requirements of the the life that these days the astronomer’s name is based on our experience about the life on earth and it can be also other things that we are not aware of and yeah and i was in this kind of thinking and then
I found myself in the middle of nowhere so i thought okay it’s better to stick to the criteria that we already know yeah yeah so i have questions but uh let’s uh tell our audiences that you can also keep posting your questions under the um video uh okay i have already some questions
Uh let me start with the questions of our audiences and then later i can continue with mine what is the likelihood of uh tests finding planets that contain organic life yeah this is a hard question to answer because this would mean i have a different let’s say
Think um fair kite in the word in english i have knowledge of things which are not yet discovered in science so this is uh this would be a wild guess and um but i personally um i think it’s much more yeah likely to find for example microbic life or traces of
A small life somewhere maybe we see traces in the atmosphere which um concludes that there could be life on that planet but a hundred percent sure um you can only be if you go there and take a probe and analyze it but this won’t be possible yeah that’s right
Uh i myself know of a recent studies that you know that except water organic molecules can be also an important criteria for having life uh interestingly people i mean astronomers could find those complex organic molecules which help them to predict a path toward finding rna
I would say it would be a very special moment when they really can find rna even though they are looking in the younger stellar objects but yeah we don’t know exactly uh it’s hard to find them in this space yes i think the next few years with the
New telescopes which are coming up there are a lot of telescopes also which ones i did mention the james webb and all other kinds of telescope also the elt in in 2025 so with those telescopes having first light i think there will be a lot of things happening the same when
Was happening when kepler was doing first light i mean this period from 2009 till 2018 i mean they regularly uh regularly were popping up um from nasa uh news like second earth found or so um there will be there will be a lot of news coming
As soon as those instruments go after a slide yes yeah that’s right uh okay the next question is that do exoplanets have liquid water on them yeah this depends on the location of that planet which circles that star so we to measure the atmosphere where we can detect traces of water
Is now a day is really difficult so they are but we can guess um about it so we know in our solar system we know how the sun works we know how the physics behind different stars work and so we can calculate the area in which the rays should be um
Still powerful enough to have a planet be warm enough with an atmosphere to to keep water liquid and um so that’s why we can say those planet could have liquid water in that area but yes but uh is it the case that all exoplanets have these i think the answer is no
No i mean um what what is when we look in our solar system for example mars a lot of scientists think there was liquid water on mars and also the range where um in the in the how it is still like on the edge of the habitat
Zone depending on what you take into account which parameters it’s inside sometimes it’s outside so um some scientists believe um that there is there was water that’s why there are so many missions now i mean um you heard probably a few missions are going to started already
This year are going to start this year and they are all looking for traces of water or life and um yeah so as in our solar system there are planets which is no water or we really have to search really really um hard for it um this is also possible for planets
Outside of our solar system that’s right okay the next question is that are the rising number of satellite constellation an issue for airspace observations it’s not clear to me are the rising number of satellite constellation uh if anybody in the community could guess what our audiences mean with this question
Uh okay we can go to the next question how much can we tell about the composition of exoplanet atmospheres at the last workplace how much can we tell about the composition of exoplanet atmospheres atmospheres yeah this is a very new topic and it’s it’s just started so um
I i remember there was an article i don’t have it right now um with me but there there um there was something beginning of this year or something that they found traces of water in an exoplanet’s atmosphere so they are already analyzing those atmospheres but um yeah this would require a small
Research of me to find out more information okay so we are looking forward to that yeah oops do you have us do you hear me yeah okay um and uh the next question uh okay great our audiences are keeping keep posting questions that’s very good why does jupiter not
Migrate inwards or did jupiter migrate involved some time ago okay i’m i’m not that into the topic of the physics of solar system but um the migration process happening in very very early stages of um of the development of a star so in this time where um the the disc the protoplanetary disc
Uh is full of gas and dust and um with that um there are different um physics comes to play which for example has to do you can look at it as we simulate it as a fluid we look at this like this and then there you can see that there are forces
Which are pulling the planet because of the capillary and rotation which are pulling the planet inwards and there are other forces because of this fluid like the gas um it behaves like fluid and that’s why we get a pull outwards and we get a pull inwards
And um in the net depending on the strength of those the fluid of those forces is either migrating inwards or outwards and this happens happened in um we think it’s a scenario um that this happened in those systems which are um which have planets very close to the stars
Because we know we we think that we know that the planet the gas the planets cannot um um develop there because of the heat and the winds you need the colder areas in the production is the stellar disc and maybe some question that is a very closer to what you already
Explained is that do we have another planetary system that astronomers have studied that closely or our information is only coming from our solar system in reality and the other information we have are based on simulations yeah um this this is i think before the first exoplanet was discovered also
We thought we know how planet formation works because we uh we studied our solar systems for several decades and we found new things but still we thought the rough the rough we understand the processes behind it and then then the exoplanets were discovered and they looked totally different so we
Needed to adapt our theory of how solar solar systems develop and so we know a lot from our solar system but as we have new insights or new information we have to expand that theory and this is possible through observations of different stages of exoplanet development for example we look in the
Infrared we can look at early stage in visible we can look at the more developed stage where the gas and gas and dust are already gone and stuff so this is very important the observation is very important but not only the observation we also need to see how those different stages fit together
And that’s where um simulations come to play to see how to connect those different stages and how physics uh very nice yeah yeah that’s right okay um do we have any idea what we what we would do if we ever found extraterrestrial life [Laughter] i think that’s a question that philosophers should
Ask yeah yeah i think when the voyagers we sent out the people we’re we’re thinking about it how to communicate with the aliens i mean they made those those symbols on the on the spaceships in case yeah aliens will find it so i think there are some people who thought about it and
A lot of movies make us have thought about it and so i don’t know maybe it would be nice if our audiences answer write their answer below this video right to see how people are thinking about that okay the other question is that do orbital resonances affect habitability yeah yeah yeah it depends
Um the i think as this stability and and the distance to the stars are um very crucial um i think um the influence so so um life can only develop if the planet has a stable orbit and yeah okay okay we so far we had a lot of
Questions from audiences let me ask my own questions um we are you can still posting your questions but meanwhile i’m going to ask mine um the first question i had was that you nicely explained what exoplanets are okay they are planets orbiting around the stars except our sun and you also mentioned that
In 2011 they could find a binary system right it was my question that if they could find any planet around a multiple system like a not a cluster but three or four stars which shows a planetary system around yeah this is probably also something about definition how you define
What is a binary system what is a multiple system because the distances between between those stars can be really far and still be connected gravitationally but just loosely so for example if a binary system a tight binary system uh could also be somehow in connection with uh
A third star but the third star is so far out that it the it’s not influenced but of course um the chances for a stable orbit the more forces um are acting on that planet it gets difficult and difficult to keep a stable orbit and not be ejected or
Pulled onto the star so so the chances are must much higher the less stars are involved and it gets more complicated with more stars and but also if the stars are really distant then per definition it could be multiple star but they are far far away
Then the other thing that comes to my mind while you were presenting different method to detect the exoplanets i was thinking uh how do astronomers know which kind of planetary system are facing these to select the best method to detect that exoplanet yeah i think it’s just surveys it’s it’s they they look
Like kepler they look at so many stars and measure them um look this one method because kepler can only mess with the transit method and they just uh it’s a chances like it’s um if you measure a lot of stars you have a higher probability of finding
Um exoplanets and this is how you do it you cannot look at the star and say this star it has an exoplanet and i will just measure this star and find the exoplanet you can you can do that if you know that star has exoplanet and revisit
Uh and re-observe that with the other telescope and to prove to revisit and see that it’s really a exoplanet that the signal is regularly and stuff this you can do with one telescope and choosing one star but to really find and hunt exoplanets you need surveys that means they just
Want to go and check the whole sky and find them okay very nice explanation and another thing that is kind of common not question it was very interesting for me that one of the criteria for finding life is to have let’s say cosmic cleaners i think you phrase it as this
It was very interesting while it seems that our solar system as a whole made earth a habitable planet right yes there are so many factors tiny things which influences um that we we are here today and talk about this topic um that um these are just a few
Major factors but of course there are south and other smaller things to play come to play when uh um doing the course of life to develop yeah yeah i have two more questions from the audience is the inclination of the heirs axes also decisive for its habitability you mean probably
Yeah i think this of course um it’s stables like it is today and also um the mild climates are also um For it depends uh if you look at life i mean there is life which is happening at volcanic areas or wherever we think there is it’s so um yeah um microbic life can happen a lot of places so it hot would be probably enough but we know for um for us
For for the other life forms which are more complex in microbes it is nice to have a climate which is not too hot not too cold and so um i think it really um helped the the different climates we have on earth to develop this variety of life yeah but um something
This is not my research topic so it is just yeah that’s right a bit far from this and one let’s say kind of technical question is that how small can a telescope be to discover an exoplanet this really depends on the system you are looking at
To discover it’s always good to have a good a big telescope in space to observe a lot of automatically but if you want to revisit one like the one maybe an exoplanet which is close to the earth which has a big um a big planet like a hot jupiter circling
You can go down like i discovered it with a 30 centimeter telescope i think maybe you can go a little bit smaller but i mean you need a telescope which is very stable you need to have accurate um yeah you have to follow it over like four or five hours accurate
So you need um you need a good ccd chip like a camera on top so um yeah i don’t think it’s possible just with your um by neculas or like a little telescope like 10 centimeters and put your normal camera behind like you need a cooled camera for that
And so um and i don’t know um probably those um institutions like observatory or something they don’t put those cameras on a smaller telescope than probably 30 or something so um it it has to be um yeah in it makes no sense to put a high detection camera on a small telescope so
That’s why i think so 30 should be okay yeah good we get a lot of questions today and i think maybe we can finish the this section of the event thank you very much davina it was very nice to have you in our second event with this inspiring presentation and topic uh
You can stay with us towards the end or if you have other things to do please feel free to leave the meeting um yeah thank you very much i’m excited uh on the other topics coming up okay great so then thank you all for accompanying us until now i hope you have enjoyed
So far and i hand over to alina for the second half of our event which is press release please alina