Yeah, I I don't know if I stand with the right spokes.
That's right. It's
that this.
The fever is not in my eyes.
So i'm going to talk about
rotation of characteristics. The
So here is the the team over all this. Some of them are in the audience.
And
this is okay.
it's
it's all that again.
So it's.
If the paper related to this, just the the the the the
okay.
and the yes. So a few words about asteroids rotation in general.
Okay, so it is. Generally it's. It's it's it's it's it's it's it's a reflected life
our by the rotation
that's right
because it shows a different section
and all regions in different. I'll be those at the different faces.
And as we can just in most cases measure this integrated
that what we see is the variation in the in the in the line curve of the of the objects. Well, I just said, here it's reflected live, but it could as well be in several admission.
But this is not going to be the topic of this talk today.
It's gonna to see.
Okay, so why why this is the thing is interesting at all.
Basically, post information about formation conditions of collisional evolution.
both for individual objects and also for larger sample of stories of populations
most asteroids retained in the so called principal.
so they they rotate around the access to the highest.
It's not always the case.
because there is a so called
or
so in some cases called public. It is considered a temporary state.
and this long it's just relaxed to in a few 1 million years.
That's because of time scale, and it's it's it's probably caused by recent collision.
It's another object.
So the traditional view of the main asteroid. But okay, so there there is a main Us. Right. But that's I think I don't have to explain this.
It's a typical thing between the orbits of.
So in the main, but
there are, say, large asteroids, which are larger than 40 kilometers.
and they
but that's the traditional view. I'm. Showing here
they have a so called Maximilian distribution. Everybody knows this from the University, but to Mexican is, I don't want to explain this.
This should be the typical outcome of a Coll. Generally involved system.
Yeah, there are smaller asteroids which are considered
to be like a 150 meters to 40 kilometers in size.
and their distribution. The fragrance distribution is strongly non-profit.
because there are no gravitational effects that
45 this distribution i'm going to talk about this later.
and there are a very small asteroids for that we say 150 meters in it.
which can be hardly had to have together by everything only.
and they are probably monolithic fragments from the coalition of
Okay.
So still, why this is this rotational thing is interesting.
and the there is this typical usual figure that
someone can drill it's talking about.
This is the diameter versus frequency. But
and you are just putting everything every asteroid, you know.
And there is. This is a strange shape.
And basically what you can see here is a
a little bit around 2 point, something hours.
and in the diameter range of a few larger than a few kilometers.
There are no Western rates rotating faster than it. This is called the the spill barrier.
So the the main understanding of the speed barrier is that if these
it was just
because there is not enough
internal strikes to keep them together, it's just a gravity that keeps them together.
it seems to be a fairly good picture, because well, because we have this area here.
Well, it
you can.
of course. What are these guys here?
These are usually very.
and these are considered to be monolithic.
so they are not at to get their back. Every t they are have together by internal strength.
and you may also ask, okay, these are usually
discovered as near as asteroids, because obviously they are very small.
So if they are very far, they
you would simply not be able to see them
all right. So the other kind of interpretation is doing basically the same.
But instead of
diameter, frequency.
spin rate attitude
plugs.
and also you can draw the the kind of constant density curves.
So what is the density that is required to keep the asteroid together? If
it it's only the gravity, then
the that's kind of a
Okay.
So another thing is so called shape reconstruction.
which is usually done through the so called.
If you have an asteroid which
it's not strict, I mean in the simplest approximation it's.
Then, if you see it from, say, between their own view.
then you have a large
I'm.
If you'll see the same asteroid
from the direction of the polls. So all of you.
then you basically see nothing, or almost
nothing in the light.
So, as the the asteroid orbits the sun.
you are going to see the the lot, the the spin access.
Always it's a different direction.
which means that you will see different.
And from all these live
you can try to reconstruct the true shape of the asteroid.
and there are very sophisticated models that they that can do this for you.
So you get the the
they usually
nowadays. We have something like a few 1,000 asteroids
for which we know these shapes through these.
Okay.
it should be so.
Yeah.
So yeah. But rotation can also determine the shape of that.
And for
okay, so the the basic thing. Maybe I can spot this. It should be video. I hope it's starting. It's for demonstration. It's the earth
which is going to update, foster and foster.
so as it
it takes
Foster.
it starts to plateau. It's a so called mentor in this period.
but there is a certain speed computation of speed at which and the application appears.
and it's. The lowest energy state is not a flat thing anymore.
It's going to deform to a shape called
this checker, Vm. I, you say, is considered, while as a
it's an easy approximation of the shape of asteroids.
So if you, if there's a
in the in the fluid. No internal strength strengths that approximation. It will be formed to this shape.
Okay.
another thing about that
is it. The driver of the long gravitational effects, the and the York effects
the apples. The fact is basically the red radiation of the absorbed sunlight.
which means a small force that pushes the rest of the
or outwards or along its orbit. So the effect, basically.
as it as I try to demonstrate it here is that the asteroid orbits the sun, which is here this way.
and the radiation is absorbed by the surface, but the so, the rare radiation, the next thing, one of the rare radiation of yours, not in the direction of the stone.
but it's a bit different angle. So let's say.
if August
on the surface is not not at the local. No, but that's 2 Pm. In the afternoon.
and this curves is a small force.
The direction of the force, whether it's, pushes the it's involved or out of it, or the rotation of the state. If it's such a great, it will move forward. If it's, probably it will move out.
If it is, of course, dependent on the
they affect the smaller and larger.
and it's also aggressive proportion of the size.
the of the asteroid.
So this is considered to be the main mechanism that can direct estimate to the nearest regime, and it's very important on the most important, the fact for potentially the service asteroids.
as it can
modify the orbit of the asteroid, you know, you know, relatively very.
There is the other fact which is pretty closely related to this. This is called the York.
It comes from the the names of these 4 guys here.
and this is that the sunlight can start to talk on the asteroid.
due to inhomogeneous surface features.
and this code is
an acceleration of the
so. This is again proportion if it's a proportional to the
at the size of the asteroid.
So the very fast rotating asteroids that we can see, or we have just seen in this figure before
was
probably it's gonna apply the New York fact.
kind of 2 effects out of 2 effects are, of course, coupled, because
if you have a different interpretation rate, then you have a different yeah of the effects strength.
Okay, so just for the if you know. But it's a pretty scope.
There was the the
which lived in the restaurant, which has a had a rotation
that was probably in the nearby.
All right.
Okay.
Okay. So
the next one. Yes, okay.
So if you want to to study.
we want to at least.
and then with you.
and of course, like pair of shape and multiple that box with the colors, if possible.
So before they meet 20 tenth majority of the.
This is also true for the.
and there is an important thing about these sections, and there are very strong biases in the experience.
determination.
what
what which usually considered in in this way. So there is a so-called report in bias.
so the not because the no detections are usually not reported.
I mean love detections
can be due to 2 small aptitude and or
to long rotation here. You
I mean it's pretty close related to this single type bias in the the goods targets.
I have rotation periods, or at least a half period
that fits into the single but
a single light which it makes it tough longer.
5. It was earlier. It should be longer than 8 other
me.
So
and
yeah. And if you just sort of a fractional life that may also lead to 4 experience.
and these problems are were usually not considered or recognized until certainly people just use the the the periods, and then they use, and
what someone reported without considering this.
So basically, we needed something that can continually measure longer than 8 are.
And the
So what is the location.
This is K. 2.
That's the most difficult mountain to, I think, in the world.
but that's why they have chosen the name.
But the the K 2 mission was the second flight mission of the capital space Telescope.
So
after the death of the third reaction Bill, so actually it had 4 at the beginning
2 of them died, so there was only 2 left.
So to effectively stabilize the the spacecraft against the solar radiation pressure.
they They found out this way
the position? They asked the the spacecraft in a way that it
it's the main accesses in the Atlantic.
so the
the radiation pressure can stabilize it.
So it's it's. There were so called campaigns which were
roughly 80 day long, observing windows
and and in this observing window, or it's campaign. The telescope looked at the same sky
she goes.
and then, because it was then moved as it was orbiting the sun.
is it moved from from the the this direction, and they tend to be the position to another fear.
But it's 8 days. It's very long. So it offered a very good possibility to observe
Well, as we are in the Atlantic.
We expected to have many
solar system targets, especially
so. Here are the fields
we had altogether 19.
The like this was interrupted.
because
because, you know, they they are now confused. Yes.
so it's. It was a a roughly about me to, and it was very effective in the sense that we could go down to 20 sort of magnitude
which can be in this sense hardly achieved by ground based telescopes, because in on on the ground you need a large
and you won't. Get
a long of serving time to observe magnitude, for example, on the large telescope.
Okay, yeah. So
you
for the
not the whole field of you was not downloaded.
You have to select the pixels of your best target
in the case of the moving objects specific. Well, what we call banana
was
selected. So it's basically the I think it should move.
Should it
please
please move.
So you can see this target here, just moving around along
this. And yeah, so that that's that's the data that you get from from a
from K. 2 for for each of these targets.
Okay, so it's a
Okay.
So there are basically lots of targets that I can say that we observe, because I think you can easily identify. I mean
familiar names
from this from this figure.
So from
from here. Thus Germany and Trojans, Iranian, irregular satellites.
main bad asteroids, and so on.
So basically
we had many papers on on different populations of small bodies in the Solar System.
And finally, there is this paper. The first author is Victoria Caps Committee. She is now in Leyden.
finishing his
somewhere around these days.
And
yeah.
So the this this for the one which say left it's it's 66,000 through the object
to collected from the data of several K. 2 campaigns.
Okay?
Oh, is it too much? Okay.
Okay.
So so there are many talk, many, many
asteroids, especially the ones in, say, more specific populations.
like the Hildas or the the German Trojan populations.
and
which were observed by K. 2, and and there were a bunch of papers on on this.
and since they were relatively bright, I mean
2010 to something.
as you're gonna see.
they they provide it very good quality life for many of these targets, and these are, for example, very interesting ones, because
you can see that it's presumably a
and these were not really the same
in the ground based observations before, and also the number of the targets for the good product targets, for example, for
was
significantly increased by this
studies.
Okay, yeah. Oh, I think the main outcome of all these
Yes.
is that there is an over abundance of long.
So oh, whatever compilation we look at either. The the here does the and the main. But asteroids
there was an overview of
long rotation really is
in the and and that's
this. We also saw later in in the test data.
and also it was confirmed in the meantime by uplast. And
so
yes.
okay.
So here is the the figure from a chin of paper. Actually
that
but you can see is
the the black is the say, the old.
the gray is the the new main bad by the
and the the
yellow and big ones. The
and what you can see is there is a significant number of
which we are not seen previously in.
Okay.
So what can we expect among the
first? They are faith.
So there! There's always going to be a determination of the
Any detective one.
It's larger than
well about the 100 kilometer
range. So if you look at these sizes, these are the largest ups customer is that you can find in the main.
and it's also. What we see is just a snapshot. Whenever the the observation was done, when they offered to stop the some very slowly, so the speed
suspect. Angles do not change much within a decade.
So what you can obtain by this is is just one amplitude.
Basically
so, and they are too distant for you and your fax to have any notable effects.
So what we see is the result of formation for additional of facts. But the long gravitational for no gravitational.
Yeah. And it is expected that there is probably a large number of binary T, and it's the rotation state can be strongly if that's by T, I mean between the 2 components of the system
in this binary.
Okay, so no, it's
Yes, it's it's. It's. It's it's it's it's critical. For
I mean we are in the 2223 magnitude range. And
well, there are there.
It's not like
the previews, Georgia, Trojans, and so on were basically
for every object object he looked at.
It was good enough to provide. The
we had 66 stargets it's 37 a period of detection, and 59 up to the Uk: that's that's how you call the non the actions.
Yeah. And there is one thing which is important to recognize here that the noise is requested.
So for the the higher frequencies it always is pretty much costs, but around, say 2
of the day it starts to increase.
and at the lowest request it is roughly a factor of 2 higher than the high.
which means that we have a lower chance to detect a long notation period and show.
Okay, so here are some
connections
I don't know. Okay. So maybe there is. There is one with the a short but with the longer rotation period.
the low frequency.
and there is one where.
yeah of the the the primary frequency is on the high here.
But of course there's also a question whether it's a single team or a double week
life. I mean, if
you assume that it's a rotating.
that the
so you can investigate whether this one or this one is the more likely one here. This is the more likely one.
So we have a lot of roughly 5 or rotation period for this target. It's. I think it's very well, detective, despite the fact that it's 22,
32 magnitude in average.
Oh.
okay.
So
all the T. And it's also slow. So it can be the it's K. 2. Yes.
there are most more slowly rotating Tnos than in the scp. The S. Cdp. Spends for the
This was this was the collection of all asteroids plantation periods
from based measurements. Basically They also include some space data now.
but
that is like
questionable fate of this. It's. It's not to be discussed here.
So the the point is that the the live blue thing is the it's let's go in the ground based data
with the peak, some that here.
and you can see that the K 2
shows much
shows
the detections at much lower for classes, so there is significant amount of slowly there slow potatoes also along
the Ts.
However, it is the very slow one in the
but this may be a selection effect due to the in case, noise at all.
And an interesting thing is that the average K. 2 T. No period is
roughly 24 h.
The previews lost in ground-based data was $8.
It's technically different from that.
Okay, yeah. You can also see here as a function of the absolute magnitude and absolute magnitude is all whole pride the an object could be for seeing
from one
as well.
So it's basically a proxy for size.
So the this means
that the size is increasing in this direction as the as we go, that is smaller.
So the Trojans and you guys are, of course, sample smaller objects than the the the the trust
simply because they are all for it for their way.
We cannot
see the small ones here, just the largest one. There is also something which is left here at CC. It's central, called Mexico. So one may ask why the called bicycles?
Yeah. So why because
the the
regular Thomas of low eccentricity or between roughly 44, 48,
you. So they they are somewhere here
and there. They are
that cause there to be 2
dynamic of groups.
The the Hope and the code. Once the the whole phones have higher inclination.
the
so what we see among the
that should should really be the the most pristine thing in the solar system.
So basically nothing happened to the cost, because in the last 4.5 billionyears.
so previews there was a study
by all
we said that, yeah, there is a difference between the
and the long, long course classical objects. It's a small say 1 h, a difference in the but it's an image. It's not really big.
but in our sample. It seems that
the in the cold
so actually the
but it's more likely to just you to the low number of.
and the real difference between the properties of these objects.
Okay.
So yes.
So it is something which we call the the
From all our sample, I think.
and only one matches
it doesn't solve. Very good.
The which it matches is this one.
It's a contact binary.
This is the the live curve with the 6 meter telescope.
Okay, it's
It's it's 22 magnitude. So
but we can clearly I detect basically the same.
I think just we cannot detect these very sharp
things due to the because it's a contact binary.
So you cannot detect this.
But the interesting thing is probably this one. This is from the
this is their
to go.
and they just do the the the period of frequency with the highest spectral power volume.
But I mean there are many others very close to it. So
which is the which is the good one? I mean. I think this is a good one. But anyway, anyhow.
and if you look at papers
about what you see is very similar to this. So someone just pick something along with the highest probability. But I mean, who knows?
So the number of
apart from our work, of course.
is considered to be roughly 10 to 20.
It's a very, very low number.
I mean all together, we had something like 120 of any kind of
which means that this is 120 is. Many of them are just upperly or something.
and they want which good quality, notation. Periods usually have a large.
I mean, these are not only rotate fast, and have live, live, but they are also the rightest objects to near region.
and
I mean Robert Sokach is going to talk about this a few weeks in in this seminar.
There is the case of Ares, which was a very interesting thing.
because the pivots work support the notation periods. Industry are
to 14.6 day range
and all with 90.9% profit us.
Of. Of course it none of them were right, because
it's it's 15.8 days.
which is.
and actually it was confirmed by independence data from a group in the Us.
They just contacted us after the paper appeared. So
it's it's pretty much this one. Yes.
so all the rotation previously in the future reliable at all. That's a good question. We have something like 20
lost the bomb
for all of which are, which can be considered as reliable.
But
oh, okay, it's a complicated to go.
So here is
cumulative number of what it's called probability, but it's a number just to mobilize it's called the Probability Cooperative number of objects with a certain
and the black one is out here.
I think there's yeah there isn't
the version of this. Just it just for me to remember what
they think. So
So the blackboard here is the is our K. 2 T. No curve. I think it's. Yeah, says this for.
and the other ones are from basically ground-based data.
I mean, the the red one is from graph based data.
Yeah, and also the the the other one is a main that
it also from ground based data.
so that you in 2,029
and
Yeah. So what you can see is that at at low aptitudes there's a huge that. That's why why I drove this yellow thing here.
So there is a huge discrepancy between
the the ground based data
and our K. 2 data. This is.
we think, mainly you to the fact that the the sections are not reported
in the ground based observations. This this can be very
extremely misleading when interpreting this figure. For example.
it goes.
What you can do is to try to to model that. What is the background? Population of objects that can produce this kind of cumulative distribution.
and, for example, just a fine.
It tries to
kind of objects. Contact binary. This is with the longer sailing, scheduling, scheduling blue.
Okay? So they scatter the reflected life in a certain way.
and the same contract binaries, but the longer it's it's, it's different kind of scheduling, though the log work is the
the most the possible
in in this. In these distances basically we is that
that's a there is a very high efficiency that
if it but it arrives from the direction of the spot, is it back to the direction of the stuff.
So these are kind of to experience. Let's say
so. What you can see is that these are the some small modifications that? And what is the ratio between the size of the components in the conflict by the system?
But you can see that it's it's very well. It is
by these these great curves, which are the contact binaries by the long birds scattering, and they
all other which you could try, and that if it's on the extremely far from this one.
So in this paper we did not want to say that.
and we have.
as we explained it, because it can be explained by probably many things, but it's interesting to see that whole different from anything as it so before.
Okay.
at all.
Yeah.
all right. You cannot see the upper part here by some reasons. But what I want to show is, it's not our work for for 2 slides
it's a it's a by.
and co-workers to summarize in a in a paper in in 2,001, and they took
all the large main asteroids and observed them by they, basically
the Via TV at the sphere, in most cases
to get a result of the.
and from this result images they determined
how these objects are.
So, for example.
the the
the property that measures how they are is here called Aspirin City.
It's basically deviation from the spherical solution of the object.
and
we, with the increasing size, the the clearly goes down.
I mean in the older of a. We are here at 100 kilometres, so 2, 300.
We are over the at the very low aspirations, so the objects are probably around
It's it's it's basically the same thing. The whole watch, the deviate from the
it describe the same thing.
Okay, there is a a slide
by us for texting. We groups You can see by the colors, because
I mean the the largest 10, sorry! The smallest ones are
A and S. 5 asteroids.
and the larger ones are
something related to C 5.
So the about from the same composition as you are going to just see here.
Yeah, because
what you can also calculate from this is, of course, that what's the average of the of the objects, I mean for s 5 or the related types.
It's rather around 3 per centimeters, so they are very rocky.
if you and probably have a low quality, and if you go for C type asteroids.
then it's roughly 1.5 cup per cubic centimeters, so head of higher for it, and probably for things. They like the material as well.
Okay, so this is another
complicated figure. I I we try to explain it.
It it all belong. I I can
so black black curve here. Okay. So what we see here is the diameter
of the objects.
Where is the
so?
The black curve is from the the the
this is the kind of average code
it's totally the life of aptitude goes down instead of aspirinity used to the life of aptitude, but
in this sense it means that if you have a smaller live kind of amplitude, the maximum.
So this this is this is the
the
Okay. So the blue are all our Tnos in different ways. That's let's just consider this one. This is the they say the good call with, considering also the
not connections.
what we see here is, there is a huge discrepancy between the 2 curves, and there is a factor of 2, 3, at least, between the and the main. That.
Why is it strange? It's changed because
Tnos consider to have lower densities
and lower internal strength, and it means that they should become a spherical at smaller sizes.
This is obviously not the case.
at least not
as a proxy for this.
so could they have a higher compressive chance. It's very unlikely
for 10, obviously a large fraction of binaries here.
maybe contact binaries. It is, of course, a possibility
what
it can also be that you can to see more of video or irrigation from the surface.
I mean, this is what we kind of.
We don't see in the main, but in the main that they, the the surface of asteroids are very homogeneous
with
the same, although practically every ref.
and this cannot be explained by the low
that it is of the character, but objects, because to have this kind this aptitudes.
the densities should be very, very low in the order of 4.1 kilometers, which is way too low, you know, for the capital.
Okay? So conclusions
or other open questions
so it could detect
long rotation period around the
i'm not confirmed. So there are a lot of targets not seen previously, so there is a hook. The whole picture about the general characteristics of the and invitation has to be considered.
and there is an overview of the
okay in in the K. To mention that's all about the populations also on Tnos. So what is the conditional or or other evolution that can lead to the observation rates.
and in general have higher.
so could it be, goes by larger audio variations or or large fraction of contact binaries. So these are the the questions that that remains of the
out of work.
And then thank you for your question.
Okay.
thank you. And
any other questions, please.