NASA once again astonishes the world by taking the first direct image of a faraway world
with its Webb Space Telescope.
Forget about consumer cameras and smartphone photographs; NASA's James Webb Space Telescope
is one of the most spectacular imaging equipment of our time.
It has and will continue to provide images of places and planets that we will never be
able to visit, as well as phenomena that are hard to imagine.
Despite the fact that the James Webb Space Telescope's live launch occurred only a few
months ago, we've already seen some pioneering and breathtakingly stunning images.
Now for the first time ever, astronomers have been able to use the telescope to capture
an image of a planet outside our solar system.
Stay with us until the end as we dive into the details of these stunning images.
The James Webb Space Telescope is proving its potential to revolutionize exoplanet research.
The vast majority of exoplanets have only been discovered by brief dips in the brightness
of the stars they orbit; only up to two dozen have been imaged directly.
But that might soon change.
The James Webb Space Telescope has given its first direct photo of a planet beyond our
solar system, less than two months after it began science operations.
The image, which was captured using four different light filters, demonstrates how Webb's powerful
infrared gaze can effortlessly capture worlds outside our solar system, paving the way for
future surveys that will reveal more information about exoplanets than ever before.
Exoplanets are often only observed inferentially—either by the minor dimming of light caused by their
orbit in front of their parent star, or by the slight wobble caused by their gravity
tugging on the star.
Actually, spotting an exoplanet is significantly more difficult since the star it orbits washes
out the comparatively small world.
It's like trying to identify a moth fluttering near a street light from blocks away, as astronomers
frequently describe it.
“This is a transformative moment, not only for Webb but also for astronomy generally,”
said Sasha Hinkley, associate professor of physics and astronomy at the University of
Exeter in the United Kingdom, who led these observations with a large international collaboration.
The planet is visible in the image as a tiny speck next to the blazing star.
It is a gas giant that orbits the star HIP 65426, which is located 385 light-years from
Earth.
Webb photographed the exoplanet using its Near-Infrared Camera (NIRCam) and the Mid-Infrared
Instrument (MIRI), each of which focuses on a distinct type of infrared light.
Taking direct images of exoplanets is tricky because stars are much brighter than planets.
This one, HIP 65426 b, was only detected due to a combination of factors.
First, it is 100 times the distance between the sun and Earth from its parent star (for
comparison, Pluto orbits only 40 sun-Earth distances from the sun).
Second, HIP 65426 b is incredibly enormous – 12 times the size of Jupiter, the largest
planet in our solar system.
In the near-infrared, HIP 65426 b is around 10,000 times fainter than its host star, and
a few thousand times fainter in the mid-infrared.
Webb, on the other hand, was able to separate the two objects due to its sensitivity.
“Obtaining this image felt like digging for space treasure,” said Aarynn Carter,
a postdoctoral researcher at the University of California, Santa Cruz, who led the analysis
of the images.
“At first all I could see was light from the star, but with careful image processing
I was able to remove that light and uncover the planet.”
The amazing thing about NASA is that it shares its discoveries with the rest of the world,
which broadens our understanding of physics and space, providing us with inspiration and
a true inspiration for the cosmos in which we live.
The image of the exoplanet HIP 65426 b released by NASA is really made up of four independent
camera views - the NIRCam instrument's view at different measurements of micrometers.
Both NIRCam and MIRI are outfitted with coronagraphs, which block the light from the central star.
"These images look different because of the ways the different Webb instruments capture
light.
A set of masks within each instrument, called a coronagraph, blocks out the host star’s
light so that the planet can be seen.
The small white star in each image marks the location of the host star HIP 65426, which
has been subtracted using the coronagraphs and image processing.
The bar shapes in the NIRCam images are artifacts of the telescope’s optics, not objects in
the scene."
"It was really impressive how well the Webb coronagraphs worked to suppress the light
of the host star," Hinkley said.
Observing the star through four different filters, the scientists eventually managed
to obtain images that reveal the planet as a small blob of light.
The blob's shape varies in each image, a by-product of the telescope's optics, the scientist said
in the statement.
HIP 65426 b is an extremely young planet, only 15 to 20 million years old (compared
to Earth's 4.5 billion years); due to its gaseous nature it most certainly doesn't host
life.
Astronomers discovered it in 2017 while operating the SPHERE instrument on the European Southern
Observatory Very Large Telescope in Chile, which captured images with a short infrared
wavelength of light.
James Webb's telescope, on the other hand, employed longer wavelengths, which assists
in uncovering ground-based details that ground-based telescopes cannot.
There are still many exciting questions that astronomers may want to answer about this
planet and the many other planets that Webb will capture in the future, such as their
chemical composition and age.
Is this the first exoplanet we've seen?
No, but it is the first from NASA's James Webb Space Telescope.
The first exoplanets were detected using less advanced technologies in the 1990s.
Thousands more planets outside our solar system have been discovered since then.
So far, four different types of exoplanets have been discovered:
• A gas giant (such as HIP 65426 b) is a massive planet comprised primarily of gas.
• Neptune-like worlds are gaseous worlds the size of Neptune.
• Super-Earth: A potentially rocky world that is larger than Earth – they may or
may not have atmospheres.
• Terrestrial: A rocky planet beyond the solar system, some of which may have oceans
or atmospheres.
The discovery of exoplanets has revealed some remarkable and occasionally scary facts about
planets in our cosmos.
Such as HD 189773b, a gas giant 64 light-years away from us, has incredibly high winds and
temperatures, causing glass shards to rain.
Or K2-18b, which scientists were thrilled about in 2019 when it was announced that water
had been discovered in its atmosphere.
Unfortunately, it was discovered that K2-18b might be covered in super-heated, super-compressed
seas where the water exists halfway between liquid and gas, meaning you'd be vaporized
if you tried to take a dip.
While this is not the first direct image of an exoplanet taken from space – the Hubble
Space Telescope has captured direct exoplanet images previously – HIP 65426 b points the
way forward for Webb’s exoplanet exploration.
“I think what’s most exciting is that we’ve only just begun,” said Aarynn Carter,
of the University of California.
“There are many more images of exoplanets to come that will shape our overall understanding
of their physics, chemistry, and formation.
We may even discover previously unknown planets, too.”
The same team of astronomers also confirmed the presence of smoke-like silica clouds in
the atmosphere of another exoplanet.
Long hypothesized, the discovery reported in recent research reveals that an exoplanet
dubbed VHS 1256 b has a violent and turbulent atmosphere covered with clouds.
Except that these clouds are formed from smoke-like silicate particles rather than water vapor
droplets.
“A better way to think of these clouds are objects that are made of tiny-particles ... except
that these silicate clouds are made of the same thing that grains of sand are made of,”
said Sasha Hinkley.
Computer models of exoplanet atmospheres have predicted for decades that these smoke-like
particles should exist in these atmospheres, but only JWST has the wavelength coverage
to definitively detect them.
In addition to clouds, the researchers discovered carbon dioxide in the atmosphere of VHS 1256
b, just days after JWST discovered carbon dioxide for the first time around another
exoplanet.
This "second time" was not widely publicized, which helps put these findings into context.
JWST is currently being put through its paces as it’s used to make the first-ever infrared
observations of the cosmos, so expect a bunch of “firsts” in the next few months.
For example, they also uncovered a turbulent atmosphere on VHS 1256 b.
“In a calm atmosphere, there is an expected ratio of, say, methane and carbon monoxide,”
said Hinkley.
“But in many exoplanet atmospheres we're finding that this ratio is very skewed, suggesting
that there is turbulent vertical mixing in these atmospheres, dredging up carbon dioxide
from deep down to mix with the methane higher up in the atmosphere.”
This discovery of “disequilibrium chemistry” on a distant exoplanet is in itself a landmark
discovery for JWST.
VHS 1256 b is a strange place.
The planet orbits not one, but two brown dwarf stars that themselves orbit each other.
It does not orbit its binary host in a circle, but rather in a highly oval "eccentric" orbit.
It's 72 light-years away in the constellation Corvus.
Its mass, which is in the range of 12 to 16 Jupiter masses, is so great that it might
really be a potential failed brown dwarf star rather than a planet.
Therefore, rather than just calling it a planet, the paper literally refers to it as a "planetary
mass companion."
“It is definitely not terrestrial,” said Hinkley.
“It’s much more like a gas giant, super-Jupiter object.”
Either way this object is roughly 360 times our Earth-Sun distance, away from its host
stars so takes a whopping 17,000 years to orbit.
Based on this first data, it appears that the telescope will outperform its expected
performance by a factor of ten.
At 100 AU from a sun-like star, it should be able to resolve a planet one-third the
size of Jupiter.
A planet like Neptune should be detectable from a red dwarf around 100-200 AU.
Webb should be able to see a planet five times the radius of Earth between 0.5 and 2.5 AU
in the nearby Alpha Centauri system.
It was a rough ride, but all the years of work on the JWST are paying off.
How many more exciting discoveries will the JWST make in the coming months?
Are you as excited as we are?
Please let us know in the comments section below.