– 3832 - WEBB DISCOVERIES - new teachings from Webb. The launch and subsequent operation of the James Webb Space Telescope (Webb or JWST) is one of the most exciting scientific events in decades. When Webb launched on Christmas Day of 2021, it was the culmination of decades of work by NASA scientists and engineers. In mid-July, 2022, Webb released its stunning first images.
--------- 3832 - WEBB DISCOVERIES - new teachings from Webb
- Within days of the telescope coming online
in late June 2022, researchers began discovering thousands of new galaxies more
distant and ancient than any previously documented, some more than 150 million
years older than the oldest identified by Hubble.
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- Webb is capable of collecting enough light
from astronomical objects, ranging from birthing stars to exoplanets, to reveal
what they are made of and how they are moving through space. This data has already begun to reveal the atmospheric
composition of planets hundreds of light-years from Earth in great detail,
offering hints as to their ability to potentially support life as we know it.
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- STARS BORN IN THE PILLARS OF CREATION in the Eagle Nebula has long been one of the
Hubble Space Telescope's most iconic images. But though the telescope, which
detects mostly visible light, captured the structure’s impressive clouds, the
"creation" happening within them was hidden.
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- Webb's infrared imaging has managed to
capture it in the form of numerous protostars. Appearing as tiny red dots
against the smoky backdrop of the pillars, these collections of dust and gas,
each many times larger than our solar system, are stars being born.
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- Gradually, as more and more material falls
in, the middle becomes denser and denser, and then suddenly, it becomes so
dense that the hydrogen burning switches on, and then suddenly their
temperature jumps up to about 2 million degrees Celsius.
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- WEBB'S FIRST DIRECT IMAGE OF AN
EXOPLANET. Scientists discovered the
first exoplanets in the 1990s, and today there are over 4,000 known worlds
orbiting faraway stars. Still, only around two dozen of these have been imaged
directly. Most exoplanets are so far away that they can only be detected
through a dip in the light of the star they are orbiting, when that planet
passes in front of its host star.
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- The planet, called “HIP 65426 b”, was
discovered in 2017. To view it, scientists used two of Webb's cameras, several
filters, and the telescope’s coronagraphs, tools which blocked out the light of
the central star. Along with the telescope's exceptional sensitivity, the
planet has several features that make it easier to observe.
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- At 100 times the distance from our sun to
the Earth, this planet is much farther away from its host star than any planet
in our solar system ( Pluto is only 40 times that sun-Earth distance from our
sun). A colossal gas giant, it’s also exceptionally large, about 12 times the
size of Jupiter.
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- RE-IMAGING THE PHANTOM GALAXY. Though the “Phantom Galaxy” is difficult to
find in the night sky, its brilliance is far from invisible, especially when
captured in infrared with Webb. Hubble's optical image of the galaxy, also
called M74, shows the galaxy's perfect spiral structure and its distribution of
stars, arms extending outward from a radiant center.
-
- But,
a new Webb image reveals fiber-like structures of heat-emitting dust and
gas, emanating from a bright center rendered in vivid electric blue. The
addition of crystal-clear Webb observations at longer wavelengths will allow
astronomers to pinpoint star-forming regions in the galaxies, accurately
measure the masses and ages of star clusters, and gain insights into the nature
of the small grains of dust drifting in interstellar space.
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- MYSTERIOUS, BOXY RIPPLES SURROUND
WOLF-RAYET STAR. In July, 2022, Webb
captured an image of a distant star, a Wolf-Rayet star, which featured Webb's
signature diffraction pattern, an imaging artifact. But around the
star,”WR140”, is a pattern that looks equally unreal, a ripple-like pattern of
concentric rings that have a peculiar, slightly boxy shape. Unlike the
diffraction pattern, the unlikely-shaped rings are real features.
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- Wolf-Rayet stars are massive stars nearly
the end of their lives, already having released much of their hydrogen into
space. The strangely shaped rings are caused by the interaction between WR140
and its smaller companion star.
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- FINDING THE MOST DISTANT GALAXIES
EVER. Webb was made to observe the most
distant galaxies in the universe, Webb observed the galaxies as they appeared
about 13.4 billion years ago, when the universe was only 350 million years old,
about 2% of its current age.
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- Scientists suspected that the four galaxies
were incredibly ancient, like hundreds of others identified by Webb. As part of
the JWST Advanced Deep Extragalactic Survey (JADES) researchers confirmed their
age, analyzing data from the telescope’s Near Infrared Spectrograph to find out
how fast the galaxies were moving away from the telescope.
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- This is the galaxies’ redshift, how much
the wavelengths of light they shed have lengthened as the universe expands.
Their redshift was 13.2, the highest ever measured.
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- LOOKING AT AN EXOPLANET’S ATMOSPHERE IN
DETAIL. A planet orbiting a star in the
constellation Virgo is now the most-explored world outside our solar system.
The planet is called WASP-39b and is about 700 light years from Earth. It is a
boiling gas giant about the size of Saturn, orbiting its host star at an
absurdly close distance, about eight times closer to its host star than the
planet Mercury is to our sun.
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- Using Webb's main camera and two of its
spectrographs, scientists identified carbon dioxide in its atmosphere, the
first time the gas has ever been found in an exoplanet's atmosphere, though the
planet's thick atmosphere is dominated by thick clouds containing sulfur and
silicates, including sulfur dioxide.
-
- Researchers were also able to use what they
learned about the planet’s atmosphere to infer aspects of its history and
formation. Scientists think the planet formed from a collision of smaller
planetesimals, and because it has more oxygen in its atmosphere than carbon,
formed much farther from its star than it currently is.
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- GLIMPSING TITAN’S CLOUDS. Saturn's moon Titan is a weird. The moon has
"rock" made of water ice, as well as rivers, lakes, and seas made of
liquid methane and ethane. It is also the only moon in our solar system to have
a thick atmosphere, a hazy one dotted with methane clouds. Scientists got a
glimpse of some of those clouds in November, 2022, when Webb captured atmospheric data from the
weird moon.
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- THE SECRETS OF THE SOUTHERN RING
NEBULA. Scientists always thought of
the “Southern Ring Nebula” as rather unremarkable. The thinking went that the
nebula was simply a dying star, called a white dwarf, that had expelled its
outer layers, which glow brightly as white dwarf radiates waves of energy.
-
- Scientists also knew that another, non-dying
star, part of a binary system, was largely obscured beneath the brightly-lit
gas. But Webb's stunning image of the nebula, released as part of its first
images and data, made it clear that it wasn't that simple.
-
- Webb imaged the cloud with two of its
instruments, the Near Infrared Camera (NIRCam) and the Mid-Infrared Instrument
(MIRI). With MIRI, researchers saw that the white dwarf wasn’t invisible, as
they’d expected in that wavelength, but glowing red, surrounded by a haze of cool
gas. Where had the gas come from?
-
- The only logical explanation, it seemed,
was that the nebula hid a third star, which was the source of the gas. The
telescope's main camera also captured intriguing shells around the out edges of
the nebula, somewhat like those around WR140. They think a third star,
somewhere between the two known ones, could have caused the ripple-like
shells.
-
- We think all that gas and dust we see
thrown all over the place in the Southern Ring Nebula must have come from that
one star, but it was tossed in very specific directions by the companion stars.
-
- WEBB DISCOVERS BROWN DWARF WITH SAND
CLOUDS. Though many telescopes have identified exoplanets, Webb wasn't designed
to. But discover one it did and it's an exceptionally weird one. For one, “VHS
1256 b” isn't a planet at all. It's a brown dwarf, bigger than a planet, but
too small to be a proper star.
-
- This one gives off a dim, reddish glow, a
product of the modified form of fusion that happens on objects that are very
massive, but too small to fuse hydrogen. Still stranger, Webb observed that the
brown dwarf has sandy, silicate clouds, a first for this kind of object. The
exoplanet is also small for a brown dwarf and therefore young.
-
- As with WASP-39b, Webb was able to identify
individual chemicals in the brown dwarf’s strange atmosphere, such as water,
methane, carbon dioxide, and potassium, among others. Ratios of the different
compounds suggest that the object has a turbulent atmosphere.
-
- In a calm atmosphere, there is an expected
ratio of, say, methane and carbon monoxide,
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.
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- A NOT-SO-CLOUDLESS PLANET. As part of its first release of images and
data from Webb, NASA released the telescope's first spectrum of the atmosphere
of an exoplanet, from a planet called WASP-96b. Webb's spectrographs analyzed
the light of the planet’s star filtered through the planet's atmosphere as it
crossed in front, obtaining a spectrum, a kind of “bar code” of the wavelengths
of light absorbed by the planet's atmosphere.
-
- The spectrum detected signs of hazy skies,
clouds, and water vapor on the planet. This is strange, considering that
scientists previously thought the planet didn’t have any clouds at all. The
planet's atmosphere has a strong sodium signature, something that researchers
thought until recently meant it had unique, entirely cloudless skies. The
results are so contradictory that scientists are reanalyzing the Webb and
previous data, trying to figure out how to reconcile the seemingly opposite
conclusions.
-
- The signs of water on the distant planet
almost definitely don't indicate that it could have life. The planet is a
"hot Jupiter", a gas giant half as massive but slightly larger than
our solar system's largest planet, it's very close to its host star, orbiting
it every 3.4 days. The surface temperature? Exceeding a 1,800 degrees Fahrenheit.
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- HIDDEN STAR FORMATION AS GALAXIES
COLLIDE. One of Webb's strengths as an
infrared telescope is its ability to peer through dust, revealing things hidden
from telescopes like Hubble, which use mostly visible light. When Webb captured
an image of two galaxies colliding, it saw something Hubble had missed, an area
of intense star formation, which scientists say is producing stars 20 times
faster than in our own galaxy.
-
- In the new image, the merging galaxies,
called “IC 1623”, contain an area of star formation that shines so bright with
infrared radiation that it produces Webb's typical pointed-star diffraction
pattern, which is usually the result of its observing bright stars. The area
makes up a completely new layer of the image, hidden from Hubble behind a thick
layer of dust.
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- Scientists think that the merging of the
galaxies, which are about 270 million light-years away from the Earth, may also
be creating a supermassive black hole, which is not visible in the Webb image.
January 10, 2022 WEBB DISCOVERIES
- new teachings from Webb 3821
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--------------------- --- Friday, January 20, 2023 ---------------------------
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