Latest / Space News Today / Asteroids, Comets & the Latest from the DART Mission: A Cosmic Update | Space Nuts: Astronomy...

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Asteroids, Comets & the Latest from the DART Mission: A Cosmic Update | Space Nuts: Astronomy... · Space News Today

0:00
Hello again and thank you for joining us
0:02
on Space Nuts, the astronomy and space
0:04
science podcast and radio show on
0:07
community radio across Australia. My
0:10
name's Andrew Dunley. Great to have your
0:11
company in this the 607th episode of our
0:15
program. Can you believe it? And this
0:17
one is 100% dedicated to comets and
0:20
asteroids in one way or another. We've
0:22
got an update on the potential impact of
0:25
asteroid Y4 with the moon. And they've
0:28
been keeping an eye on this and they've
0:30
come up with an answer and it's uh it's
0:32
really clever the way they've done it.
0:34
Uh more news out of the Dart mission.
0:36
Something else has happened there. Yes,
0:38
it's on a collision course with nothing.
0:40
Had you worried there for a moment and
0:42
three Atlas is chemically unstable. In
0:45
fact, it's falling down drunk. We'll
0:47
tell you why on this episode of Space
0:50
Nuts.
0:51
>> 15 seconds. Guidance is internal. 10 9
0:55
Ignition sequence start. Space Nuts.
0:58
>> 5 4 3 2
1:01
>> 1 2 3 4 5 5 4 3 2 1
1:03
>> Space Nuts.
1:04
>> Astronauts report. It feels good.
1:07
>> Joining us again for another stint on
1:10
this little podcast of ours is Professor
1:12
Fred Watson, astronomer at large. Hello,
1:14
Fred.
1:15
>> Hello, Andrew. And uh it's nice to talk
1:17
to you. What a surprise.
1:18
>> Good to see you.
1:22
And we have got um a um a real rocking
1:26
program today.
1:27
>> Oh, I love it. Love it.
1:28
>> It's all about rocks and ice and
1:31
asteroids and something else which we'll
1:33
get to later that's not rock and ice. Uh
1:36
but um first an update on the potential
1:39
impact of asteroid Y R4 with the moon.
1:43
were a little bit worried that its
1:45
chances of hitting the moon were well I
1:47
think I heard in the early stages of its
1:49
discovery that people were quoting 20 or
1:52
30% chance of it hitting the moon that
1:55
kind of got wound back to a more
1:56
reasonable number. Uh but now they've
1:59
got some definitive
2:01
evidence of what's going to happen
2:05
that that's correct. Um, I mean, uh,
2:08
it's not just the moon that worried us
2:11
for a while with asteroid 2024 YR4.
2:15
uh because when it was discovered back
2:18
in 2024, as you might guess, uh Y4
2:22
um when its trajectory was analyzed and
2:26
you got to remember that an object is
2:29
only 60 mters across um which is flying
2:32
through space, you make observations of
2:35
its position. uh and if you've only
2:37
observed it over a short period of
2:39
period of time, the uncertainties in its
2:42
well both its past orbit and its future
2:44
orbit are very large. So it's what we
2:47
call the arc uh the arc of observation.
2:50
The the wider the arc of observations
2:52
that you can make, the more accurate is
2:54
going to be your assessment of where
2:57
it's come from and where it's going. Um
3:00
and so those early assessments uh
3:02
actually they were in early in 25 2025
3:05
when these calculations were made. Um
3:07
but it's it did suggest a small chance
3:09
that it might hit the earth.
3:11
>> Uh and that was very quickly I think I'm
3:14
sure you and I talked about this on
3:15
space.
3:16
>> Yeah, we did.
3:16
>> It was very quickly ruled out. Uh and
3:19
but as it sort of wandered on its way uh
3:23
early in 2025, uh there was still a
3:27
possibility that it might hit the moon.
3:31
Uh and the time that it would happen
3:34
would be uh 2035
3:37
uh was the uh basically the the targeted
3:41
time for sorry no is that right? 2032
3:44
>> 2032.
3:46
Yeah. Yeah, that's correct. Sorry, I'm
3:48
mixing up my numbers. You deserve when
3:51
you get to a certain age.
3:53
Uh 2032
3:56
um that there was a non-zero chance that
3:59
it would hit the moon. And the the story
4:02
what happened then was of course this
4:05
object is it's what we call a near-Earth
4:07
asteroid because it approaches near the
4:09
Earth, but it's not near the Earth all
4:11
the time.
4:12
>> Most of the time it's a long way away as
4:14
it goes around in its orbit around the
4:16
sun. and it sort of disappeared from
4:19
view essentially certainly from the uh
4:21
from the purview of groundbased
4:24
telescopes. There was not going to be
4:26
any way we thought of observing it again
4:28
until 2028 when it would make another
4:32
close approach, not one that had any
4:34
risk attached to it. But we didn't
4:36
expect uh to be able to see its position
4:39
in any detail until 2028, which we would
4:42
need in order to predict where it might
4:44
be in 2032, whether it's going to hit
4:47
the moon or not. Um but um there are
4:50
some scientists at uh who use the James
4:53
Web Space Telescope who tend not to let
4:57
uh faintness stand in their way because
5:00
that's why you couldn't observe this
5:01
object. It was just too faint. And sure
5:04
enough, uh early this year, last month
5:06
in fact, they've made two sets of
5:08
observations where they've actually
5:10
picked up uh the image, a tiny faint
5:13
image of uh 2024 YR4. Uh they've picked
5:18
it up and uh allowed um them the
5:21
calculations in uh to basically take
5:24
those new positions, the 2026 positions
5:28
into the orbit calculation. Uh, and what
5:31
they've done is they've ruled out any
5:33
possibility of it hitting the moon. So,
5:37
that's an unexpected story for us. I
5:40
didn't think we'll be talking about this
5:41
again until 2028. Uh, but no, we've
5:44
talked about it in 2026 and the web
5:46
telescope has come to the rescue. Um,
5:48
some people are disappointed, Andrew,
5:50
because um,
5:51
>> an asteroid hitting the moon uh,
5:53
especially if you know when it's going
5:54
to happen and you would know where it
5:56
was going to happen as well. Uh, could
5:58
have produced some um quite interesting
6:01
pyrochnics. It would allow spectroscopy
6:04
uh, which would tell you a little bit
6:05
about the asteroid's makeup as well as
6:07
the the makeup of the lunar regalith and
6:09
the lunar lunar um, terrain that it
6:12
smashed into. But that's not going to
6:13
happen. Uh and so for anybody like
6:16
astronauts who might happen to be
6:17
hanging about on the moon in 2032 and
6:20
there may well be both uh Chinese
6:22
tyonauts and uh western astronauts on
6:25
the moon by then. We'll um that that
6:28
will be a great relief I'm sure.
6:30
>> Yes. Yes. You don't really want a
6:32
mission interrupted by a piece of an
6:34
ice. Uh what would could you if if it
6:38
did hit the moon? Let's just play that
6:40
card for the moment. uh and you were
6:43
looking at it at the time, would would
6:44
you actually see it with the naked eye
6:46
or with a telescope?
6:47
>> I don't think you would with the naked
6:48
eye, but you certainly would with
6:50
telescopes and even maybe a relatively
6:52
small telescope. We've known I mean
6:55
certainly since the 1950s,
6:58
uh that rocks do hit the moon. Um and
7:02
often these are ones that are much
7:04
smaller than the 60 m of Y4. Um it's for
7:10
a long time I remember you know when I
7:12
was first getting into astronomy in the
7:14
1950s uh that um people talked and in
7:18
particular Patrick Moore talked about
7:20
these what what were called TLE's uh
7:22
transient lunar events uh and there were
7:26
flashes basically that amateur
7:28
astronomers kept reporting said every so
7:30
often there'd be something you know
7:32
they'd be looking at the moon through a
7:33
telescope and suddenly there'd be a
7:35
flash. uh and for a long time it was not
7:39
show not known really whether this was
7:41
due to some sort of residual volcanic
7:44
activity on the moon or whether it was
7:46
impact of asteroids and and large meteor
7:49
meteorites. Uh and um it was really once
7:53
we seen the Apollo results and got to
7:56
know the moon a lot better because of
7:57
the Apollo missions that it it was
8:00
deemed to be impacts that caused these
8:02
transient lunar events. uh and so uh it
8:05
would certainly be a 60 meter object
8:08
hitting the moon is quite significant uh
8:10
and that I don't think it would be naked
8:12
eye visibility but I you probably
8:15
wouldn't need that big a telescope to be
8:17
able to see it.
8:18
>> Wow.
8:18
>> And so yes so yeah interesting
8:21
>> and especially you know sorry especially
8:23
if you could predict when and where it
8:24
was going to happen you'd have all the
8:26
amateur astronomers in the world of that
8:28
side of the earth facing the moon. Yeah
8:31
with eyes glued to your telescope. Yeah.
8:33
Um, now just need you probably to
8:37
explain how this works. But, uh, the
8:41
scientists using the James Web took
8:43
images 8 days apart. Is that that's
8:47
obviously significant because then they
8:49
get a straight line uh, observation. Is
8:52
that how it works?
8:54
>> No. What what happens is um, uh, in fact
8:57
what even just one of those observations
9:00
would have been invaluable. two is
9:03
devastatingly invaluable. It makes it,
9:05
you know, it increases your accuracy
9:07
even more. Uh because what they do, they
9:10
combine those new observations with what
9:14
we knew from its orbit the last where
9:17
when we observed it in 2024 25. So what
9:21
you've suddenly got is you've you know
9:23
the arc of observation might just have
9:25
been a few months at the end of 2024
9:27
early 2025. Now what you've done is
9:30
you've extended that arc by a year
9:34
effectively. Uh and that gives you a
9:36
much much more accurate uh value of of
9:41
uh what we call its orbital elements.
9:43
The the asteroid um is its orbit is
9:47
actually delineated by six numbers. Uh
9:51
and those are the orbital elements as
9:53
they're called. uh those numbers uh get
9:56
more accurate the more uh the longer you
9:59
can observe it for. So and and it's not
10:01
just the how long you can observe it
10:03
for. It's the interval between you know
10:05
what's the interval of time between the
10:07
observations which is what we've got
10:08
here. We've suddenly got observations
10:11
made a year later. It's it's absolutely
10:14
narrowed down the uncertainties in the
10:15
in the orbital elements. And so what we
10:18
can then do is another great word from
10:21
those orbital elements we can generate
10:23
what's called an ephemeris and ephemeris
10:25
tells you where the asteroid is going to
10:27
be. It's a future predictions.
10:29
>> That was what my MSE was on uh making
10:32
orbital elements and uh fem
10:36
of asteroids with a really new invention
10:39
called computers.
10:41
Yes. Yes. That I think that'll be a big
10:43
hit.
10:45
Well, it might be, hopefully not
10:48
depending on where you're standing. It
10:50
was certainly I'll tell you it was a big
10:51
hit with the um with the external
10:53
examiner, a gentleman in Glasgow
10:55
University by the name of Archie Roy. He
10:57
said, "Oh, this this work should be
10:59
published. People should be able to read
11:01
about this." Uh it never was, but uh the
11:04
one copy is actually behind me.
11:08
>> Yeah, it's one of the two thick volumes
11:10
at the end. The other's my PhD thesis.
11:13
I keep thinking of questions while we
11:15
talk about this. Um, but what I what I
11:18
find extraordinary is that the James Web
11:20
Space Telescope was trying to find
11:22
something 60 m in size from a distance
11:26
of 48 million kilometers, 30 million
11:29
miles.
11:29
>> Yep.
11:30
>> And it found it twice.
11:31
>> It's pretty fantastic, isn't it?
11:33
>> It would just pop above the the
11:36
background noise. you know, when you
11:37
when you're doing these observations,
11:39
you've got various sources of what we
11:42
call noise, which is basically
11:43
uncertainty. Uh, and um, these are
11:46
probably
11:47
very close to that noise level, but it's
11:50
just shown up enough that gives them
11:52
what they call what we call a three
11:54
sigma certainty. It's, you know, that's
11:56
the level of certainty that you need.
11:57
It's just a technical term for the
11:59
statistical analysis that's being used.
12:01
>> Um, I maybe they got help from AI as
12:04
well. I don't know.
12:05
>> Maybe. Yeah, it's possible. Um, I have a
12:08
doomsday question though.
12:10
>> Great.
12:11
>> When, and we're going to talk about the
12:12
dart mission next because there's new
12:14
information about that uh, deflection
12:16
test. But when do you intervene? Like if
12:20
if we left it a couple of years because
12:24
James Webb couldn't find it and then we
12:26
realized it was going to hit Earth or
12:28
something to that effect. When is it too
12:31
late to intervene? it it's um with an
12:34
asteroid like that it's almost too late
12:37
already uh because you've only got so if
12:40
we'd observed this in 2028 and the
12:42
probability of an impact with Earth had
12:44
gone up I mean it that had disappeared
12:47
long ago so it's it's not a problem but
12:49
if that happened you've only got four
12:52
years uh and we're not ready quite yet
12:57
to mount an emergency mission I think
13:00
down the track we will be Having seen
13:02
what come out of the story we're going
13:04
to do next and
13:05
>> um I think down the track we will have
13:08
uh probably planetary defense uh rockets
13:12
and spacecraft almost ready to go uh so
13:14
that you could think about deflecting an
13:17
object if it looked as though it was
13:18
going to impact the earth but I suspect
13:21
with four years that's not very long for
13:24
a modified orbit to evolve into one that
13:26
will miss the planet altogether. Um, uh,
13:30
I think what would happen would be you'd
13:32
you'd mobilize a civil defense, uh,
13:36
resources because you'd probably quite
13:38
quickly get an idea where the collision
13:40
was going to be. You'd have a a circle
13:42
of uncertainty, but you would know
13:44
roughly where it was, which which side
13:46
of the planet was going to be facing it.
13:49
uh and a 60 m object. I mean, it's
13:53
probably twice the size of what exploded
13:55
over Chelabinsk uh in 2013. And we know
13:59
that that caused structural damage when
14:03
the shock wave hit the ground from 30
14:05
kilometers high and it was the broken
14:08
glass that caused all the injuries.
14:09
Nobody died. Uh but but people did get
14:12
injured. Um, and if you knew something
14:14
like that was going to happen, uh, then
14:17
you'd get the people out or get them in
14:19
bunkers or whatever. Um, because it that
14:21
that would be the most likely scenario,
14:23
an air burst. It may be what happened at
14:25
Tangaska actually.
14:26
>> Yes.
14:29
>> Yeah. I think the latest theory is it
14:32
was actually a atmospheric graze rather
14:35
than impact and caused
14:37
>> explosion downwards. Yeah.
14:40
>> Rading radiating out. Um the images from
14:42
that are incredible. You can look them
14:44
up on
14:44
>> all the trees.
14:46
>> Yeah. Just flattened. Unbelievable.
14:48
Yeah.
14:49
>> If you would like to read about the the
14:51
latest observations uh regarding
14:53
asteroid 2024 YR2, you can go to the
14:56
scienceblog.com website or you can go to
14:58
the issa website where they've published
15:00
the findings. This is space nuts with
15:03
Andrew Dunley and Professor Fred Watson.
15:06
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16:39
I believe that this nation should commit
16:41
itself to achieving the goal before this
16:45
decade is out of landing a man on the
16:48
moon and returning him safely to the
16:50
earth.
16:50
>> These nuts.
16:52
>> Well, we said we'd talk about it and we
16:53
got to talk about it. The Dart mission.
16:56
I think we should start by kind of just
16:58
revisiting what that mission was all
17:00
about and why. Well, we know why. to see
17:03
if we could move something that may hit
17:06
Earth one day off a bit so that it
17:08
missed us. Uh I probably just explained
17:11
it, but um yeah, this was four years
17:13
ago, wasn't it, Fred?
17:14
>> Uh indeed it was. That's right. 2022. Um
17:17
it was I think it was it September. Uh I
17:20
can't remember.
17:21
>> Good question.
17:22
>> About I think it was about then. Um the
17:25
so a really really clever experiment uh
17:29
conducted by NASA and a team of project
17:33
scientists. Uh what do you do to test
17:36
whether you can move an asteroid? What
17:39
you don't do is slap something into an
17:42
asteroid and see whether you can change
17:44
its orbit around the sun. And that's
17:46
because uh the orbits of planets,
17:49
asteroids um and comets actually as well
17:52
are very very stable. It's quite hard to
17:54
change them. Uh because you're talking
17:56
about, you know, lots of rather large
18:00
forces, gravitational forces and things
18:02
like that. So what they did was they
18:04
said, "Okay, we won't do that. What
18:06
we'll do is we'll find an asteroid with
18:07
a a moon." Uh and we now know there are
18:10
a lot of those. And they chose an
18:12
asteroid called Ditimos. Uh if I
18:15
remember rightly about half a kilometer
18:16
across uh which had a little moon called
18:19
Dorphos which is about I think 170 m is
18:24
the figure that comes to mind. This
18:26
little moon that goes around Diddimos
18:28
once in I've got a feeling remembering
18:30
it was about 11 hours its orbital
18:32
period. So you smash something into the
18:34
little asteroid moon. Uh, and what you
18:38
then look for is how the orbit of the
18:41
moon around its parent body, in other
18:43
words, the moon, the orbit of Demorphos
18:45
around Ditimos, how that changes because
18:48
something on that scale is much easier
18:50
to change than the orbit of an asteroid
18:53
around the sun. Uh, and as we all know,
18:56
it was incredibly successful. the orbit
18:59
of the orbital period of um Demorphus I
19:03
think it was reduced by was it 33
19:04
minutes I think was the the figure um if
19:08
I remember rightly the Dart spacecraft
19:11
I'm remembering these numbers from the
19:13
last time we talked about it I think it
19:15
was um uh three tons I think thereabouts
19:20
hit Demorphos at 6 kilometers/s
19:24
caused a huge plume of data sorry a huge
19:27
plume of debris not data, lots of data
19:29
as well, but debris too. Um, and that
19:33
was all in fact visible from Earth as
19:35
well as from uh things like the Hubble
19:37
Space Telescope. Uh, so it was a
19:40
experiment that was well uh devised,
19:44
well set up and had excellent results.
19:46
It did exactly it did better than what
19:49
um the mission scientists hoped. And the
19:51
reason why it did better was because
19:53
they there was a much bigger effect.
19:55
It's when you hit something at 6
19:57
kilometers/s, everything's vaporized.
20:00
The the surface that you hit, which is
20:02
actually a rubble pile, but the surface
20:04
you hit vaporized, as is the spacecraft
20:06
itself, and that vapor acts like a
20:09
rocket exhaust. So, it's not just the
20:11
nudge that you get from knocking
20:13
something weighing three tons into an
20:15
asteroid. Uh, it's also the sort of
20:17
exhaust effect that comes from that uh
20:20
as well. Um, so it uh and that that was
20:25
what was very hard to quantify. We
20:27
didn't really know what that would be,
20:28
but it was enough to make a significant
20:30
difference. So that's the backstory,
20:32
Andrew.
20:33
>> Yes. And you were right. It was the 26th
20:34
of September, 2022.
20:37
>> Okay.
20:37
>> Great. Yeah.
20:38
>> Yeah.
20:40
Do you want to just check the mass of of
20:42
the dart impactor while you're looking
20:44
there? So
20:45
>> correct if I've said it wrong. I said
20:47
three tons, but I might be wrong. I
20:49
can't remember. Okay, I'll do that. Um,
20:51
but I guess we could uh move on to
20:54
what's actually happened now. They've
20:55
done more analysis and and something
20:58
spectacular has happened as a
20:59
consequence of that event three and a
21:01
half years ago.
21:02
>> And the way it's happened is neat as
21:05
well because uh what you're looking for
21:08
um if you're looking at the way an
21:11
asteroid change an asteroid orbit
21:13
changes, you're looking for incredible
21:16
precision in space. uh and there are
21:19
limits as to how precise we can get uh
21:22
those measurements using telescopes.
21:25
It's all about the position in space of
21:26
the object. Telescopes are great at that
21:29
of course but there is a better way uh
21:33
for asteroids and that is to use
21:35
occultations and an occultation is when
21:38
an object like an asteroid passes in
21:41
front of a star and you can predict this
21:45
is going to happen. So what you do is
21:48
for an object that's only 170 m across
21:52
uh which is the size of demorphos um you
21:56
you you've got what you do is you space
21:59
astronomers along a line uh who are
22:02
observing and because you you're not
22:05
quite sure where the shadow of the
22:07
asteroid casting the light of the star
22:10
is going to fall. But with telescopes,
22:12
what you can do is you can see the dip
22:14
in a star's light as the asteroid passes
22:17
in front of it. It's what we call
22:18
noultation. And if you've got enough
22:20
observers on the ground, it gives you a
22:23
much higher level of precision as to
22:25
where in the sky that asteroid is. And
22:28
so that process was carried out um I
22:31
think last year. Um and uh so that means
22:35
that you've suddenly got very very
22:37
accurate measurements of the position
22:40
not just of of Dimorphus itself but also
22:42
the parent asteroid Ditimos. In fact, I
22:45
think it might be Ditimos um that was
22:48
used for the occultation. And so the
22:50
bottom line is uh that uh lo and behold
22:56
it didn't just the impact didn't just
22:58
change the orbit of Demorphos around
23:01
Dillimos. It changed the orbit of the
23:03
whole system, the pair of them around
23:06
the sun. And that is the first time, one
23:10
of the nice quotes in one of these
23:11
articles, it's the first time a
23:13
humanmade object has measurably altered
23:15
the path of a celestial body around the
23:17
sun. That's in a NASA statement.
23:20
>> That is incredible. And of course, the
23:23
obvious question is now, will we be able
23:25
to track where it will go versus where
23:27
it would have gone?
23:29
>> Yes. And and indeed that's already sort
23:31
of already happening because there'll be
23:34
further observations and it's the same
23:36
as we were just talking about in regard
23:37
to Y4. The longer the arc of
23:40
observations you've got, the more
23:41
accurate uh your knowledge of its orbit.
23:44
Now um the change in orbit is not much.
23:47
Um I can't remember how many days um
23:52
I've got the paper in front of me
23:54
actually the the main paper. um it
23:58
doesn't actually give us the the orbital
24:00
period of the pair around the sun but
24:02
they've changed that orbital period by
24:05
wait for it it's.15 of a second so it's
24:09
very I mean it's a matter of um you know
24:11
it's it's these two orbit between the
24:15
between the um orbits of Mars and
24:17
Jupiter they're part of the main
24:18
asteroid belt so they're their orbital
24:21
periods are probably measured in sort of
24:23
thousands of days or at least high
24:25
numbers of hundreds of days uh and to
24:28
change that by 0.15 of a second is not
24:31
very much. It speaks wonders for the
24:34
volumes for the uh accuracy with which
24:36
the orbit has been determined. But uh
24:39
it's look it it's it's it happened. It
24:41
has actually happened that we've changed
24:44
the orbit of an asteroid by hitting it
24:47
or hitting its little moon in fact by uh
24:50
with with a with a massive object. Did
24:52
you manage to find out how much it
24:53
weighed? 610 kg.
24:56
>> Okay. That's 840 pounds.
24:59
>> Yeah. So, it's less than a ton. Half a
25:01
ton. Yeah. I apologize for three tons.
25:04
That was the number from something else.
25:06
>> I reckon if they if they could have got
25:08
three tons up there, they would have
25:09
used it.
25:09
>> They would have done. Yeah. But but that
25:11
makes it even more spectacular. You
25:13
know, something weighing less than a car
25:16
clouting a the moon of an asteroid can
25:19
change the orbit of that asteroid and
25:21
its parent body. Um just to very quickly
25:25
since we're talking to a educated and
25:27
erodendite audience here the mechanism
25:30
by which that changed is so you think
25:33
well you've hit the you've hit the moon
25:35
asteroid how does that change the orbit
25:37
of the parent asteroid and what it does
25:40
hitting the moon asteroid gives you a
25:42
slight change in the position of the
25:44
barry center that's the center of mass
25:47
of the two objects their center of
25:49
gravity combined and it's that that has
25:53
changed its orbit. It's the Barry center
25:55
which of course includes both of the
25:57
objects. The Barry center is
25:58
representative of both Ditimos and
26:00
Dimorphus because it's the center of
26:02
mass between them. So changing the
26:04
position of the Barry center or the
26:06
orbit of the Barry center essentially
26:08
changes the orbit of the asteroid which
26:10
means that would something like that
26:13
threatening the earth and you had enough
26:15
enough years down the track for its
26:18
orbit to evolve so that it would miss
26:19
the earth. Uh, that might be a way to do
26:22
it.
26:22
>> Yeah, I know a few people named Barry
26:24
and they're always wanting to be the
26:25
center of attentive.
26:29
>> It had to cut, didn't it? Yeah, it did.
26:31
It did. Uh, it's a it's a great story.
26:34
It's a great read. Uh, you can pick it
26:36
up on the NASA website or you can go to
26:38
fizz.org.
26:40
Phys.
26:42
I got to do that from now on because
26:43
somebody came to us one day and said, "I
26:47
can't find this fi.org
26:49
thing
26:50
>> cuz it's not it's fizz phys uh yes but
26:55
uh it's great news out of that
26:56
experiment three and a half years post
26:59
event this is space nuts dunley with
27:02
professor Fred Watson
27:08
>> base here the angle has landed
27:10
>> space nuts
27:12
>> now to another piece of rock that has
27:16
been getting a lot of attention in
27:18
recent times I Atlas, the exo comet or
27:21
exoaststeroid. Is it a comet or an
27:23
asteroid? Fred,
27:24
>> comet. Comet.
27:25
>> Comet. Yeah. Uh, yeah. It appears that
27:27
it's um it's very different from
27:29
anything we've seen before to the point
27:31
where it's uh raging through our solar
27:33
system, stone drunk off its face.
27:38
Not quite, but uh its chemical makeup is
27:40
just way out of kilter with what we
27:42
would have expected.
27:45
>> Uh that's right. So, you know, this is
27:47
uh three eyeatlas is definitely the gift
27:49
that keeps on giving um because um what
27:53
we've got is a free sample from another
27:55
solar system that is careering through
27:57
our own solar system and near enough for
28:00
our telescopes to get details of it.
28:02
It's now actually receding from Earth um
28:06
and from the sun, but it's still
28:09
producing um gases from its icy surface.
28:13
It behaves exactly like a comet would
28:16
from our own solar system. Gets near the
28:19
sun. Uh the ice is basically turn into
28:22
gas directly. They sublimate and uh what
28:26
then happens is um we can sense what
28:29
gases are there, what what chemical
28:32
compounds are there by looking at the
28:33
spectrum of the what we call the coma of
28:36
the comet. That's the fuzzy area around
28:38
it that's caused by all this outging
28:40
material. And so, um, comet 3i Atlas has
28:44
recently been the subject of pro
28:47
probably the world's most powerful,
28:49
well, certainly the world's most
28:51
powerful millimeter wave radio
28:52
telescope. Uh, the array in the high
28:55
country of the Atakama, uh, the Alma
28:58
telescope, the Atakama large millimeter
29:00
submill array. Um, at about 5,000 mters
29:04
high, not very far from San Pedro de
29:06
Atakama. Uh, and when I went to try and
29:10
get in their back door one time, I
29:11
nearly um died because the air was so
29:14
thin and we didn't get in the back door
29:16
either.
29:18
So, uh, never mind. Uh, ALMA is fabulous
29:22
telescope. So, what's the story? Uh,
29:24
ALMA uh, which is run by various
29:29
different organizations. uh but the
29:31
scientists who have been observing a
29:33
three-ey atlas with it have looked at
29:36
the fingerprints the spectral
29:39
fingerprints of two molecules. One is
29:42
methanol which is a type of alcohol and
29:45
the other is hydrogen cyanide uh HCN.
29:49
It's a an organic molecule very common
29:51
in comets. Uh so both of those are found
29:55
in comets in the solar system. But what
29:58
is the surprise is the amount of
30:00
methanol. Uh it's as the um NRO
30:06
National Radio Astronomy Observatory
30:08
press release says uh ThreeI Atlas is
30:11
heavily enriched in methanol compared to
30:14
hydrogen cyanide. Far beyond what is
30:17
typically seen in comets born in our own
30:19
solar system.
30:20
>> You know, you know what it is, Fred?
30:23
>> Wait for it. You're gonna love this one.
30:25
It's inroxinated.
30:28
>> Oh
30:32
yes, I'll go with that. I um I know I
30:35
can just invented a new word. Well, he
30:37
did. Yes. And you probably need to be
30:39
reasonably in Roxinating in order to
30:41
invent it.
30:42
>> Yeah, I suppose so. And it's so early
30:45
anyway.
30:45
>> Yes. So early in the day. That's right.
30:47
>> Anyway, um the observing team just
30:50
coming back to a state of back perfect
30:52
back to reality, perfect sobriety. Um
30:55
it's um methanol to hydrogen cyanide
30:59
ratios of between 70 and 120 uh which
31:05
means it's among the most methanol rich
31:09
uh comets ever discovered. There's been
31:11
a few in the solar system that have got
31:14
high levels of methanol, but this is,
31:17
you know, it's up there on the extreme
31:20
end of this distribution. Um and and if
31:23
I may, I'll just read from there's a
31:25
very nice uh National Radio Astronomy
31:27
Observatory press release on this uh
31:30
which says these measurements imply that
31:32
the icy material from three Atlas was
31:35
formed by or experienced very different
31:39
conditions uh from those that shape most
31:42
comets in our own solar system. Previous
31:45
work with the James Webb Space Telescope
31:46
has shown that ThreeI Atlas had a coma
31:49
dominated by carbon dioxide when it was
31:52
far from the sun. And these new ALMA
31:54
results add methanol as another unusual
31:57
detail in its chemical inventory. It's a
31:59
very nice paragraph. So, it is unusual.
32:03
It's an object that shows all the
32:06
characteristics of a comet, but we're
32:07
seeing all the extremes. And and maybe
32:10
that shouldn't surprise us because it we
32:12
do know it has come from somewhere else,
32:14
not our own.
32:16
>> Prompts the question, does that mean
32:18
where it's come from might be quite
32:20
different to our system?
32:22
>> Yeah, that it's Yes, that's right. It
32:23
could, you know, it it would certainly
32:26
lead credibility to any idea that um
32:30
chemical ratios within other solar
32:32
systems are not necessarily what we find
32:35
here in our own solar system. In other
32:38
words, you know, there could be quite
32:39
different chemistry going on
32:41
particularly in the early history of
32:43
those solar systems. We think a lot of
32:45
these compounds like methanol and
32:47
hydrogen cyanide. Uh we think a lot of
32:50
these are formed very early in the
32:52
history of a solar system in the cold of
32:55
space. Molecules, atoms combine together
32:58
to form molecules. And we know that
33:00
there is a very very rich chemistry out
33:03
there which was kind of unexpected
33:06
really. I mean when I was a young
33:07
astronomer we thought always in terms of
33:10
just elements. The elements that we can
33:12
see in the atmospheres of stars,
33:14
hydrogen, carbon, calcium, uh iron, all
33:17
of those. But now such a lot of what we
33:20
do with the um you know with the arsenal
33:24
of wonderful astronomical instruments
33:26
that we have today. We can look at the
33:28
chemistry of these things, the actual
33:30
chemical reactions that uh go on in the
33:33
laboratory of deep space.
33:35
>> Yeah. Uh, some something you don't know
33:36
about Fred is he's been in astronomy so
33:38
long that he got in trouble at school
33:40
once for throwing an apple at Isaac
33:42
Newton. So,
33:44
true story.
33:45
>> Yeah. Yeah. Yeah. Yeah. Yeah. I got the
33:47
cane for that. But
33:48
>> yeah, I got the cane a lot at school,
33:50
too, but not for throwing apples. I did
33:52
throw a sandwich at a teacher once, but
33:54
um yeah, I was egged on to do that and I
33:56
fell for it.
33:57
>> Was it silly?
33:58
>> No, no, I can't remember what was on.
34:00
Probably something hideous that I ate
34:02
when I was a kid. If you ragged on, it
34:04
must have been an
34:05
>> Yeah, that was was a very silly move and
34:08
I'll always regret it. Um, okay. So, if
34:11
you want to read about that uh what u
34:14
constitutes a um a rather drunk rock in
34:17
space, you can go to the NA National
34:19
Radio Observatory website where they've
34:21
published their findings. And Fred, that
34:24
brings us to the end. Thank you so very
34:26
much.
34:27
>> It's a great pleasure, Andrew. Always
34:28
good to chat. And we'll see you again
34:30
next time. We will on a Q&A edition. Uh
34:34
Fred Watson, Professor Fred Watson,
34:35
astronomer at large, joining us every
34:37
week, twice a week in fact, for Space
34:40
Nuts. And uh if you would like to visit
34:42
our website, please do. Uh one thing we
34:44
could use for our Q&A episodes, uh audio
34:47
questions, we are desperately short of
34:49
them. There's some weird quirk that at
34:52
the beginning of every year they dry up,
34:54
and we don't know why that is an
34:55
anomaly, but it is a thing. Uh but if
34:59
you go to our website
35:00
spacenutspodcast.com
35:02
and click on the ask me anything tab at
35:04
the top, it's just labeled AMA. You can
35:06
send us your questions or comments. We
35:08
uh welcome them. Don't forget to tell us
35:10
who you are and where you're from. And
35:12
thanks to Hugh in the studio who
35:14
couldn't be with us today because he
35:15
went out on a bender last night and got
35:17
inroxicated. Boom boom. And from me,
35:21
from me, Andrew Dunley, thanks for your
35:23
company. See you on the next episode of
35:24
Space Nuts. Bye-bye. Space Nuts.
35:27
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35:29
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35:31
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