Natasha Hurley-Walker: How radio telescopes show us unseen galaxies
ناتاشا هيرلي - ووكر: كيف ترينا التليسكوبات اللاسلكيّة المجرات الغير مرئية
Natasha Hurley-Walker uses novel radio telescopes to explore the universe at some of the longest wavelengths of light. Full bio
Double-click the English transcript below to play the video.
when I was just six years old,
كنت في السادسة من عمري،
that the universe had to offer.
they took me on a journey,
to become a professional astronomer.
خبيرة في علم الفلك.
a starship anytime soon.
فضائية في المستقبل القريب.
is strange, wonderful and vast,
غريب، رائع وشاسع،
to be explored by spaceship.
اكتشافه من خلال مركبة فضائية.
to astronomy, to using telescopes.
الاستكشاف من خلال التلسكوبات.
an image of the night sky.
of our local galaxy, the Milky Way.
مجرة درب التبانة.
to a darker part of the sky,
موقع أكثر ظلمة من السماء.
of our Milky Way galaxy
hundreds of billions of stars.
a local corner of our universe.
زاوية محدودة لكوننا.
a sort of strange dark dust across it.
المظلم الغريب عبرها.
استكشاف زاويتنا الصغيرة من الكون.
our little corner of the universe.
like the Hubble Space Telescope.
مثل تلسكوب هابل الفضائي.
have put together this image.
observing just a tiny patch of the sky
مراقبة بقعة صغيرة جداً من السماء
held at arm's length.
اليد من مسافة ذراع.
hundreds of millions, billions of galaxies
أو مئات المليارات من المجرات
I can continue this journey.
أستطيع أن أكمل هذه الرحلة
use a very powerful telescope
استخدام تيلسكوب قوي جداً
if we just do that.
تكون قد تجاهلت شيئاً بارزاً.
everything I've talked about so far
يستخدم إلى حد كبير
just the thing that your eyes can see,
باستطاعة أعينكم رؤيتها فقط،
of what the universe has to offer us.
مما يمكن للكون أن يعرضه.
problems with using visible light.
في استخدام الضوء المرئي.
on all the other processes
that I mentioned earlier.
الذي تحدثت عنها سابقاً.
from getting to us.
من الوصول إلينا،
into the universe, we see less light.
كلما أصبحت رؤية الضوء أقل.
with using visible light
الضوء المرئي
a busy street corner.
زاوية لشارع مكتظ.
the siren just to mess with you.
فقط لأجل العبث معكم،
as the ambulance approached,
الإسعاف تقترب منكم
the sound waves were stretched,
تتمدد الموجات الصوتية،
and they appear bluer.
أكثر زرقة.
and they appear redder.
أكثر احمراراً.
blueshift and redshift.
والتحول الأحمر.
from everything else,
everything appears to be red.
تبدو حمراء اللون.
more deeply into the universe,
أعمق وأعمق في الكون،
are moving away further and faster,
بشكل أبعد وأسرع،
to peer deeply into the universe
you know, before the redshift kicks in.
كما تعلموا، قبل حدوث التحول الأحمر.
using this for decades.
affectionately known as "The Dish."
والمعروف وبشكل ودي باسم "الطبق".
that receive across a large band.
تتلقى موجات على نطاق واسع جداً.
to the center of the Milky Way?
عند توجيهه نحو مركز مجرة درب التبانة؟
straight through dust, so not a problem.
لا يعيقها الغبار، لذا لا توجد مشكلة.
of the Milky Way is aglow,
synchrotron radiation,
السنكروتروني،
spiraling around cosmic magnetic fields.
حول المجالات الكونية المغناطيسية.
strange tufts coming off of it,
with our own eyes.
interpret this image,
it's very low resolution.
أطوال موجية طويلة،
what is the color of everything in here.
للأشياء هناك.
of the Murchison Radio Observatory,
مرشيسون اللاسلكي،
to build radio telescopes.
اللاسلكيّة:
لا شبكات واي فاي، لا شيء.
أو تأثير اللاسلكي،
to build a radio telescope.
working on for a few years
a little time lapse of it being built.
and postgraduate students
والدراسات العليا
to build a radio telescope.
these radio dipoles.
الراديو الثنائية معاً.
a bit like your FM radio or your TV.
ترددات المذياع أو التلفزيون
across the desert.
covers 10 square kilometers
there's no moving parts.
to central processing units.
over the entire desert
resolution than Parkes.
bring them to a unit
بالوحدة
to a supercomputer here in Perth,
very interesting data
on supercomputers
المعالجة المركزية على الحواسيب العملاقة
of the entire southern sky,
All-sky MWA Survey,
but it hasn't been shown yet,
ولكنها لم تعرض بعد
of the entire sky.
بأكملها
some images from this survey.
بعض هذه الصور من هذه الدراسة.
is no longer dark with dust.
لم يعد مظلمًا بالغبار.
our nearest galactic neighbor,
of its more familiar blue-white.
الأزرق و الأبيض
Let's take a closer look.
دعونا نأخذ نظرة عن قرب عنه.
towards the galactic center,
that I showed you earlier,
التي عرضتها سابقاً،
has gone up by a factor of a hundred.
مئات المرات.
the lowest frequencies red
المنخفضة بالأحمر
tell us about the physical processes
عن الأحداث الفيزيائية
along the plane of the galaxy,
we see little blue dots.
سترى نقاطًا صغيرةً زرقاء.
is that they block the red light,
about these star-forming regions
and the color tells us that they're there.
فتخبرنا أنها هناك.
around the galactic plane,
gathering up material,
mystery to astronomers
لدى علماء الفلك
of high-energy electrons in the plane
ذات الطاقة المرتفعة في المستوى
radiation that we see,
by supernova remnants,
good at detecting supernova remnants,
في اكتشاف المستعرات النجمية،
a new paper out on that soon.
I wanted to go further.
أريد أن أذهب أبعد.
interesting object in the top right,
أشياء مهمة في الزاوية اليمنى،
two huge plumes going out into space.
ضخمين يظهران في الفضاء
between those two plumes,
are only visible in the radio.
we wouldn't even know they were there,
لن تدرك أنها هناك،
than the host galaxy.
What's producing these jets?
that we know about
That's why they're called that.
ولهذا سميت بهذا الاسم
of the light around them,
or a cloud of gas comes into their orbit,
من الغاز في المدار
glows brightly in the x-rays,
can launch the material into space
يمكن أن يطلق المادة في الفضاء
one radio galaxy. That's nice.
لاسلكيّة واحدة، هذا لطيف.
at the top of that image,
and that's just because it's further away.
black hole at its center
at nearly the speed of light.
than what I've shown here.
the full extent of the survey,
of these radio galaxies.
من هذه المجرات اللاسلكيّة.
supermassive black holes.
and it will be published next week.
of the galaxy with this survey,
even more in this image.
to the dawn of time.
it was a big bang,
as a sea of hydrogen,
and galaxies switched on,
from neutral to ionized.
is at very low frequencies.
of any of the objects in my survey.
sensitive enough to pick up this signal.
حساس للغاية لالتقاط هذه الإشارة.
radio telescopes in the world.
a new radio telescope,
تلسكوب لاسلكي جديد،
times bigger than the MWA,
من مرشستون الحقل الواسع،
and have an even better resolution.
tens of millions of galaxies.
stars and galaxies switching on,
ABOUT THE SPEAKER
Natasha Hurley-Walker - AstronomerNatasha Hurley-Walker uses novel radio telescopes to explore the universe at some of the longest wavelengths of light.
Why you should listen
Dr. Natasha Hurley-Walker recently completed an astronomical survey of the entire southern sky, revealing the radio glow of our own Milky Way galaxy as well as hundreds of thousands of distant galaxies: the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey. Unlike previous work, GLEAM is the first "radio color" survey, observed across such a wide range of frequencies that the unique spectrum of every object can be used to understand its underlying physics.
An Early-Career Research Fellow based at the Curtin University node of the International Centre for Radio Astronomy Research, in Perth, Western Australia, Hurley-Walker is part of the international Murchison Widefield Array (MWA) collaboration, spanning thirteen institutes across six countries. At her fingertips are tens of petabytes of data collected by the MWA since 2013, which she processes using powerful supercomputers at the nearby Pawsey Centre. Hurley-Walker earned a PhD in Radio Astronomy at the University of Cambridge by commissioning and using a new radio telescope to perform its first science observations. The experience directly transferred to the MWA, which she also helped to commission.
The MWA is a precursor to the Square Kilometer Array (SKA), what will be the largest radio telescope in the world, set to come online in the 2020s. By developing software and techniques to deal with data from the MWA, creating pathfinding maps of the sky and training a new generation of astronomers in cutting-edge techniques, Hurley-Walker is working to lay the scientific groundwork for the commissioning of the SKA. In 2016 Hurley-Walker was awarded an Australian SKA Fellowship in order to visit the SKA headquarters and transfer lessons from her commissioning experiences as well as develop her survey into a useful calibration model for the SKA.
Hurley-Walker is passionate about scientific outreach and keynoted talks in 2013 and 2017 at Astrofest, Australia's largest public astronomy festival. So that anyone in the world can see the sky with the same radio eyes as her, she created the GLEAMoscope , an interactive online viewer that shows the universe at radio wavelengths compared to other frequencies, including the more familiar "optical" spectrum. It being the 21st century, there's also an app: check out GLEAM on the Google Play store. In 2017 Natasha won the "Best Timelapse" category in the Astofest astrophotography competition with her colleague John Goldsmith for their creation of a composite video showing both the optical and radio sky. For more detail on Hurley-Walker's work, check out her article on TheConversation.
Working with cutting-edge data is tough, but sometimes hides serendipitous gems which Hurley-Walker has unearthed, like the faintest dying radio galaxy ever discovered, whistling plasma ducts in the Earth's ionosphere and some of the youngest and weirdest radio galaxies ever found. View a complete list of Hurley-Walker's publications.
Natasha Hurley-Walker | Speaker | TED.com