James Webb Confirms its First Exoplanet: What We Know!
Welcome to the fascinating world of exoplanet exploration! Today,
we proudly announce the confirmation of the first exoplanet discovered by the James Webb
Space Telescope: LHS 475 b. This far-off world is virtually the same size as Earth, and lies 41
light years away in the constellation Octans. The James Webb Space Telescope was launched in
2021 and is the world’s premiere space observatory. It is equipped
with the most advanced infrared cameras and spectrometers, allowing it to make stunningly
precise measurements of stars and planets. Scientists are especially excited about LHS
475 b because of its proximity to Earth. This makes it an ideal target for exploration and
further study. We are beginning to understand the conditions necessary for planets to support life,
so every new discovery like LHS 475 b helps us get closer to that goal.
Exoplanet exploration is truly one of the most thrilling endeavors of our time.
With the James Webb Space Telescope, and other cutting-edge technology, we are
slowly unraveling the mysteries of the universe. Perhaps one day, our descendants will explore LHS
475 b in person. Until then, we will continue to observe this mysterious planet from afar.
Join us on a journey to uncover the mysteries of this distant planet and its implications for our
own solar system. From transits to spectra, we'll explain the research that's being done right now
to unravel the secrets of our universe! ---
It has been long established that our solar system is not alone in the universe,
with more and more exoplanets being discovered every day. Today, an exciting discovery has
been made - a new exoplanet, named LHS 475 b has been confirmed by the James Webb Space
Telescope. It’s located in a constellation, 41 light years away, called Octans. The exciting
part is that it’s almost exactly the size of our planet Earth, at 99% of its diameter. This is a
major breakthrough in our understanding of the universe, and the implications of this discovery
could be far-reaching. The planet concludes a full orbit around its star in two-Earth days,
making it perfect for observations. We have been able to observe two full transits.
Researchers using NASA’s JWST have taken an exciting step forward in exploring new
realms of science: Identifying and studying rocky exoplanets orbiting red dwarf stars.
Why is that so important? Although red dwarfs are much smaller
and less powerful than the G type stars like our Sun, they are still advantageous to detect
exoplanets due to their size and energy output. Due to the fact that red dwarf stars live longer
and have relatively low radiative power, their exoplanets, such as those in the Trappist-1
system, Proxima Centauri, and Barnard's star, are closely studied for the potential of habitability.
Since they typically orbit much closer than planets around other stars, they are
considered viable candidates for habitability that could exist for a very long time.
Check out our video on the Trappist-1 system for more information!
The James Webb Space Telescope has enabled researchers to observe planets smaller than
Jupiter for the first time, potentially leading to new discoveries about the Milky Way galaxy.
With the confirmation of LHS 475 b by the James Webb Telescope, scientists and researchers can now
begin to focus more of their attention on studying the rocky exoplanets orbiting red dwarf stars.
This research will help us better understand the complexity of our universe and hopefully,
one day, lead us to discovering Earth-like habitable planets.
Nevertheless, there are two issues to consider with the
hypothesis of red dwarf exoplanets being capable of sustaining life.
One of the discoveries made is that many of the planets close to their star are tidally locked,
meaning that only one side of the planet is always facing the sun. A planet that is
tidally locked could potentially be habitable, yet it would certainly present a challenge.
It is particularly significant to note that red dwarf stars emit a large number of potent solar
flares, especially during their earlier stages of life. These intense radiation and particle
flares could be detrimental to any life on a dwarf exoplanet, and may even permanently
sterilize the atmosphere of the planet. Although observations have not suggested that this scenario
is certain or even present, the red dwarf flaring has been documented extensively.
Thus, the flares may have made it seem improbable for life to exist on approximately three-fourths
of the stars in our galaxy. ---
How do we detect the presence of a distant planet? One of the main methods is called the transit
method. The transit method is a way to detect the presence of a distant planet orbiting a star.
Scientists measure the light coming from the distant star, and look for regular changes in
the star's brightness. If a planet is orbiting the star, it can block a small fraction of the star's
light. As the planet passes in front of the star, it will cause a decrease in the star's brightness.
By watching for this decrease in brightness, astronomers can detect
the presence of a distant exoplanet. So what did James Webb do to contribute?
The James Webb Space Telescope is like our eyes in space. On the 31st of August 2022, when it looked
at a star called LHS 475, it saw something special - a planet was traveling across the star, like a
shadow. By watching how the star's brightness changed over time only when the planet passed,
we can learn more about this planet. The infrared telescope was able to detect the exoplanet LHS
475 b by observing two of its transits across the star thanks to the sensitivity it’s doted with.
As you can see in this beautiful plot, taken from the telescope’s Near Infrared Spectrograph ,
starlight from LHS 475 is being blocked while the planet is transiting it, causing the light
curve of the star to significantly decrease. It goes back to normal, which is the first hint that
the decreases is due to an exoplanet and not to intrinsic change in the star’s brightness.
--- What’s the next step after such a discovery?
Of all the ongoing telescopes, only the James Webb Space Telescope is
equipped with the ability to characterize the atmospheres of exoplanets the size of Earth.
Researchers used data to analyze the transmission spectrum of the newly detected Earth-sized
terrestrial planet, but are still unable to see much yet, whether or not it has an atmosphere.
An atmosphere is made up of different gases and it can tell us a lot about the planet,
whether it can contain life, and how it might evolve. Scientists are trying to figure out
if this planet has an atmosphere, so they can see if it is a good place for us to explore!
What’s a transmission spectrum? A transmission spectrum is like finding
out what different colors are in a rainbow. When a planet passes in front of a star, the planet's
atmosphere can act like a colorful filter, making the starlight look different. By looking at how
the light changes, scientists can figure out what colors are in the atmosphere of the planet!
This graph shows us how much light is blocked from a star when we look at the planet from
different distances. Different molecules in the planet’s atmosphere make the planet look bigger
at certain distances. If we don’t see any bigger distances in this graph it means that there are
no molecules in the planet's atmosphere. The team was unable to determine the type
of atmosphere present on exoplanet LHS 475 b, however, they can exclude the presence of a
terrestrial-type atmosphere like methane, similar to that of Saturn's moon, Titan.
A line that is flat in a transmission spectrum, such as this one, can be
quite intriguing – it can provide us with a wealth of information regarding the planet.
As this spectrum indicates, Webb did not detect any element or molecule in a substantial quantity.
Spectroscopic signatures of hydrogen in the atmosphere of an exoplanet,
such as LHS 475 b, are typically indicative of a light, gaseous atmosphere. However, these elements
were not observed in the exoplanet's spectrum. The methane atmosphere indicated by the green
line does not block enough light in the 3.3 micron range, suggesting that the planet does
not have a methane atmosphere. The yellow line indicates the model which the best represents a
featureless spectrum with no atmospheric evidence of the planet. This model is
suggestive of a planet without an atmosphere. The team also acknowledges that while it is
plausible that the planet may not have an atmosphere, certain atmospheric compositions
such as a pure carbon dioxide atmosphere have yet to be eliminated as possibilities.
Many debates have been ongoing about the difficulty of detecting the presence
of a 100% carbon dioxide atmosphere. The researcher, Lustig-Yaeger, is saying that
it is counterintuitive because the atmosphere is so compact that it is hard to detect using
the measurements they have available. The team is planning to obtain additional measurements this
summer that may give them more precise readings for detecting carbon dioxide atmospheres.
The James Webb Space Telescope has detected clouds on the exoplanet, indicating that the
planet could be similar to Venus, with a carbon dioxide atmosphere and thick clouds. The planet
is also much warmer than Earth, contributing to the possibility of a Venus-like atmosphere.
--- We've only just begun to scratch
the surface of the universe. With the help of the James Webb Telescope, we can now confidently
confirm the existence of a planet that could potentially harbor life. We can only hope that
future study and exploration of LHS 475 b will help us uncover the mysteries of our universe.
Until then, we can be assured that the future of exoplanet exploration holds incredible promise.
And so, until then, let's keep searching the stars and never forget to look for aliens along the way!
You've reached the end of this video, if you have a theory on your own,
on whether there's life outside of Earth, don't hesitate to let us know
in the comments! We are interested in what you think! Thank you for watching! See you later.