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Ep333: James Webb Telescope · Kidcast Daily

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  Spin the wheel, Let's take a ride.
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  Sports and science bursting from inside a world of wonder.
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  Open wide. Come.
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  On. Kids, let's amplify kid cats.
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  Daily starts your day. Fun and laughter come your way.
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  Sports and trivia games galore. You're tuned in to kick ass
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  daily. From sports and science to
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  history and technology, we got the coolest stories and facts
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  waiting for you. Today we are exploring the James
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  Webb Space Telescope, a powerful observatory that helps
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  scientists study space in amazing detail.
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  You might hear people call it JWST for short.
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  It orbits far beyond our moon and collects light from objects
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  that are very far away. By studying that light,
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  scientists learn about how stars and planets form, what distant
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  galaxies look like, and what ingredients are in the
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  atmospheres of planets around other stars.
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  First, what makes this telescope special?
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  It was built to study infrared light.
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  Infrared light is a kind of light your eyes cannot see, but
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  some devices use it. ATV remote sends infrared
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  signals to your television. Warm objects also give off
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  infrared energy. Space is full of infrared light
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  from stars, gas, dust, and planets.
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  JWSD is designed to catch this light with great sensitivity.
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  It can pick up very faint signals because it stays
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  extremely cold and blocks heat from the sun and Earth with a
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  giant sunshield. Now let's talk about the mirror.
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  JWSD has a primary mirror that is 6.5 meters wide.
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  Instead of 1 solid circle, the mirror is made of 18 hexagon
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  shaped segments that work together.
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  The mirror segments are very light and strong because they
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  are made of beryllium. After reaching space, tiny
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  motors adjust the segments so they act like one smooth mirror.
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  This perfect focus lets the telescope produce sharp images
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  and precise. Keeping the telescope cold is
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  very important. Heat would create extra infrared
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  signals that could confuse the instruments.
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  To stop that, JWSD uses a 5 layer sun shield.
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  Each layer reflects and releases heat away from the telescope.
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  The layers are made of a special material called Captain, covered
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  with thin coatings that help reflect sunlight.
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  When the sun shield is properly unfolded, the instruments can
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  cool down to around 50 Kelvin, which is extremely cold.
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  One instrument, called Miri, needs to be even colder, and it
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  uses a cryo cooler to reach a temperature below 7 Kelvin.
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  Where is JWSD in space? It operates near a spot called
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  the Second LaGrange Point, or L2.
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  This point is about 1.5 million kilometers from Earth in the
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  direction opposite the Sun. At L2.
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  JWSD can keep the Sun, Earth, and Moon all in the same
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  direction, which makes it easier for the Sun shield to block
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  their light and heat. From there, it has a clear and
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  stable view of space for long observations.
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  JWSD carries several instruments that work together.
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  NIR Cam is a near infrared camera that takes detailed
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  images and helps focus the mirror segments.
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  NIR SPEC is a near infrared spectrograph.
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  A spectrograph spreads light into its colors, which reveals
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  what elements and molecules are present.
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  Miri, the mid infrared instrument, does both imaging
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  and spectroscopy at longer wavelengths than NIR Cam and NIR
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  SPEC can see. There is also a fine guidance
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  sensor that helps the telescope point steadily at its target so
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  images do not blur. Another science instrument
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  connected with the guidance sensor can also study exoplanets
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  and distant galaxies. Let's connect this to real life
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  experiences. Imagine looking at a street in
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  foggy weather. Your eyes see mostly the mist,
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  and distant buildings look hidden.
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  Infrared light can pass through dust better than visible light.
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  Many places in space of dust, such as the clouds where stars
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  are born. By collecting infrared light,
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  JWSD can detect stars forming inside dusty regions and study
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  their surroundings in detail. It can also look at exoplanets
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  by measuring tiny dips in a star's light when a then it
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  passes in front of it. By analyzing the Starlight that
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  filters through a planet's atmosphere, scientists can find
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  gases like water vapor, carbon dioxide, or methane.
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  Did you know that JWST sends its data back to Earth using radio
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  signals? Large antennas on the ground
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  receive the data and send it to scientists.
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  Teams all over the world process the information and share the
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  results. That means new discoveries show
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  up online, where people can see the images and learn from them.
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  The telescope looks at targets chosen by researchers, including
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  galaxies formed not long after the universe began to cool,
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  dusty disks around young stars, and planets orbiting stars that
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  are not like our sun. Here's a trivia question.
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  From which spaceport did JWSD launch into space?
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  It launched from the Guiana Space Center in French Guiana
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  using an Ariand 5 rocket. Now a yes or no question.
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  Does JWST have wheels inside that spin to help it point the
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  telescope without using fuel all the time?
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  Yes, they're called reaction wheels and they control the
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  telescopes orientation very precisely.
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  Let's explore how JWST stays on target.
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  The fine guidance sensor locks on to guide stars to keep the
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  telescope steady. Reaction wheels and small bursts
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  from thrusters handle slow drifts and occasional
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  adjustments. The Sun shield always faces the
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  Sun, and the mirror and instruments face the darkness of
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  space. This layout keeps temperatures
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  stable and prevents heat from reaching the sensitive
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  detectors. JWSD also has a careful
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  schedule. 1 observation may last hours, while another might
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  require several days. During a long observation, the
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  telescope collects light patiently.
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  The longer it looks, the more light it gathers and the fainter
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  the objects it can detect. Computer programs combine many
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  exposures to make one clean image and to build accurate
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  Spectra. Here's another trivia question.
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  What's super thin metal coats? JWS DS mirror segments to help
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  them reflect infrared light efficiently.
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  Gold. The layer is about 100
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  nanometers thick. Many people and organizations
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  work together on JWSD. Engineers plan the mirror
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  segments, tested the sun shield folding, and design the
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  instruments. The telescope was assembled and
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  tested in giant clean rooms to keep dust away.
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  Vibrations and cold temperature chambers made sure it could
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  survive launch and the conditions of space.
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  After launch. In December 2021, JWSD traveled
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  for several weeks to reach L2, then unfolded its sun shield and
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  adjusted its mirror segments 1 by 1.
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  Only after many checks did it begin taking science images.
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  Try this yes or no question is 1 of JWS DS science instruments
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  provided by Canada. Yes, the Canadian Space Agency
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  contributed the fine guidance sensor and a science instrument
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  used for near infrared studies. Here comes a bonus trivia
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  question that reveals a clever tool.
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  How many tiny adjustable doors called micro shutters are inside
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  the NIR spec instrument to let scientists observe many objects
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  at once? About 248,000.
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  Opening different patterns of shutters let's the instrument
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  collect Spectra from many galaxies or stars in a single
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  pointing. What are some discoveries?
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  JWSD has shown detailed structures in Star forming
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  regions, measured the atmospheres of exoplanets, and
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  found very distant galaxies that formed early in cosmic history.
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  It also looks at planets in our own solar system, like Jupiter
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  and Saturn, giving information about clouds and temperatures.
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  It studies comets and asteroids to learn about the materials
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  that built planets. Because it observes infrared
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  light, it can pick up heat signatures and chemical
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  fingerprints that other telescopes might miss.
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  Let's add a final yes or no question to stretch your
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  thinking. Does JWST carry astronauts for
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  repairs or science work? No, it operates independently
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  and is not designed for crew visits.
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  Did you know that the ground teams can update JWSD software
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  engineers upload new instructions to improve how it
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  points protects its instruments or plans.
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  Observations. Updates help solve small issues
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  and keep the mission efficient. The telescope also has rules for
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  safety, like automatic protections if sunlight could
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  bounce into the instruments, and careful limits on how fast it
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  moves from one target to another.
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  If you want to imagine the timing of its work, think about
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  a school day full of classes. Different subjects need
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  different tools in the same way JWSD switches among instruments
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  depending on the science goal. For Galaxy surveys, it may use
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  NIR Cam for wide field imaging. For atmospheric studies of
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  exoplanets, it uses spectrographs to read the
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  chemical fingerprints in Starlight.
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  For cooler dust and gas, Miri becomes the main instrument.
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  Let's recap what we learned today.
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  JWSD is a Space Telescope that studies infrared light, which
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  our eyes cannot see. Its 6.5m mirror is made of 18
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  segments that form one powerful surface.
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  A5 layer Sun shield keeps it cold, and a cryocooler chills
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  one instrument even more. It operates near the L2 point,
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  about 1.5 million kilometers from Earth, so it can block heat
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  and light from the Sun, Earth and Moon at the same time.
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  Its instruments, including cameras and spectrographs, take
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  sharp images and detailed Spectra to reveal how stars,
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  planets and galaxies form and change.
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  Reaction wheels and a fine guidance sensor keep it steady
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  and ground. Teams plan observations and
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  receive data. We added extra facts through
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  questions about its launch site, reaction wheels, gold coated
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  mirrors, Canadian contributions, and the Micro Shutter Array.
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  JWSD continues to deliver discoveries that help scientists
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  understand our universe with clarity and detail.
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  Grab your breakfast feelings fine adventures waiting here.