The universe is a place with endless possibilities. Before Edwin Hubble discovered
the existence of the cosmos, scientists had always been curious about what exists
beyond the blue skies. These days, we know most of the answers; however,
recent images from the James Webb Telescope show that we may not know as much as we think we do.
Welcome to FACTNOMENAL. In today’s video, we’ll discuss
the most recent space discoveries using the James Webb Telescope.
THE JWST. The 20th century was
a crucial time in the history of astronomy. Virtually everything we know about space is
based on the discoveries made during this time. With what little technology was available then,
scientists searched through the cosmos, looking for factual answers to the questions
there are so many other answers for: “how was the universe formed? What exists beyond our planet?”
The more answers were found, the more questions were formed, and the deeper into space scientists
had to look to find the answers. In the 1990s, the Hubble Telescope considered God’s gift to science,
was adequate for space exploration. Hubble’s contribution to astronomy cannot be overstated,
but three decades later, scientists are at the limit of what the Hubble telescope has to offer.
The James Webb Space Telescope was launched into space in December 2021,
thirty years after its predecessor. The JWST, primarily designed to conduct infrared astronomy,
was created to facilitate deeper space exploration based on results from the Hubble telescope.
Although many people consider the new telescope a replacement for Hubble, the JWST is just a cooler
and more technologically advanced substitute. The JWST is the largest and most powerful
telescope in space. Unlike the Hubble, which orbits the earth, Webb orbits the sun at a
distance of 1.5 million miles from earth. The JWST was built to carry out four main goals: study
planetary systems and the origin of life, observe the first stars and galaxies after the big bang,
study star and planet formation, and study the formation and evolution of galaxies. But how is
the JWST designed to carry out these big goals? The JWST observes the universe through the
infrared portion of the electromagnetic spectrum, which is one of the advantages the JWST has
over its predecessor. Hubble studies the universe mainly through visible light and
ultraviolet light. Let us consider the visible and infrared views of the Monkey Head Nebula.
Notice how the infrared view on your right is sharper and more detailed than the view from
visible light on your left. Well, why is infrared more useful in observing space?
The universe is covered in cosmic dust and cloud. In most cases, galaxies and planets of
interest are located behind clouds and dust, which absorb visible light. Because most of the visible
light gets trapped within cosmic dust, the images produced by the Hubble telescope are not as bright
as they should be. Infrared light, however, passes right through the dusty surrounding,
revealing whatever is inside it. The JWST has a wide collecting area
which is about 6.25 times larger than that of the Hubble telescope. Its gold-plated
primary mirror has a diameter of 6.5 meters and consists of 18 individual
hexagonal mirrors. Because of its larger field of view, higher resolution, and infrared sensitivity,
the JWST can see objects that are too early, distant or faint for the Hubble to detect.
Due to the time it takes for light to travel, the more distant an object is in space, the farther
back in time we’re looking. With the ability to see up to 13.6 billion light years away,
the JWST can see as far back into the universe as the formation of the first galaxies and stars.
This is another huge improvement from the Hubble, which can only
see these galaxies after formative periods. The JWST was built with a solar shield which
will help the telescope stay cool and protect it from light from the sun, earth, and moon.
Its components must be at a temperature below negative 380 degrees Fahrenheit to effectively
pick up faint infrared rays. Unfortunately, overheating isn’t its most imminent problem.
In May 2022, the JWST suffered permanent damage from a series of asteroid attacks.
However, despite the harsh environment of space, JWST still provides scientists with the most
detailed view of the universe. THE PERFECT EINSTEIN RING.
In JO418, a very distant galaxy, the JWST captured a perfect picture of an Einstein ring. The galaxy,
located about 12 billion light years away, is one of the oldest galaxies in the universe.
The Einstein ring observed is a phenomenon that happens due to the gravitational
lensing caused by massive cosmic objects. When he came up with the theory of relativity,
Albert Einstein predicted gravitational lensing; however, there hasn’t been
an observed occurrence as perfect as this newly detected Einstein ring. When light
from a glowing cosmic object, like a galaxy or star, passes near a massive object, the ring
of light created is called the Einstein ring. When this happens, gravitational lensing causes
the light to get diverted, and the source, lens, and observer appear to be aligned,
making the light appear like a ring. In this case, the JO418 galaxy is located directly
behind a massive galaxy, so massive that its gravity distorts the space-time around it.
As light produced from JO418 travels, it reaches this massive galaxy – the blue light at the
center of the ring – and travels through the distorted space-time. To an observer on earth,
the light from the distant galaxy appears to be traveling in a circular motion when in essence,
it is traveling in a straight path and is much farther than it appears.
The image was posted on Reddit by a user and astronomy grad student with the username
“spaceguy44”. This anonymous astronomer downloaded the image from publicly accessible
data collected by the Mid Infrared Instrument on the JWST. The image was edited, and although
it is not the first picture of JO418 since its discovery in 2020, it is the most detailed.
In the caption for the image, Spaceguy44 mentioned that the light was only obvious
because of the ability of gravity to bend light. “Without the lensing effect,” he wrote, “the
galaxy would probably look like most distant galaxies: a small blob of light.”
Using the Hubble telescope, NASA has discovered many Einstein rings in the past, but none of them
are as perfectly shaped or visible as this one. Considering the more advanced features
of the JWST, astronomers hope it’ll be easier to observe more Einstein rings in the future.
OTHER IMAGES CAPTURED BY THE JWST. HIP 65426 b.
For the first time since its launch in December 2021, the JWST has captured its first image of an
exoplanet. The planet, dubbed HIP 65426 b, is a gas giant without any rocky surfaces
and nine times the mass of Jupiter – the largest planet in our solar system.
From a 2020 analysis of the planet’s atmosphere, it was found that the massive planet was rich
in oxygen but poor in carbon, making it incompatible with life. As you would expect,
the quality of the JWST image of the planet is far superior to that of the Hubble telescope.
Scientists are excited by the prospects of the JWST, believing that previously unknown planets
and galaxies could be discovered. SMACS 0723.
Among the first pictures captured by the JWST is SMACS 0723, a galactic cluster 4 billion light
years away from earth. According to NASA, the photo of this galactic cluster is the highest
resolution photo that has ever been taken that deep into space. The infrared captured by the JWST
in this photo traveled for over 13 billion years. The Hubble telescope has been used to observe this
area in the past; however, the image from JWST provided much more information than the image
taken by the Hubble telescope. Southern Ring Nebula.
The Southern Ring Nebula is an example of a planetary nebula which is basically a cloud
of gas that expands around a dying star. The JWST captured two different highly defined
views of the nebula, allowing NASA scientists to make previously impossible observations.
From the telescopic images, scientists can tell apart the different stars within the nebula as
well as their respective functions. For example, the central star is responsible for the sculpting
of the surrounding nebula, a barely visible star at the lower left, which is the source
of the nebula, has given off at least eight layers of gas and dust over several thousands of years,
among many others with intriguing significances. Carina Nebula.
The Carina Nebula is one of the largest and most visible nebulae in the night sky, consisting of
many highly luminous giant stars – stars bigger than the sun. From the new JWST pictures,
which NASA has described as “craggy mountains on a moonlit evening,” previously obscured areas
of star formation have been revealed. Many of these newly forming stars were
in phases that typically last fifty to a hundred thousand years, which is not very long in cosmic
terms. Thanks to the JWST's high sensitivity, NASA captured an incredibly rare cosmic moment.
That’s a wrap on this video. Thank you for watching FACTNOMENAL.