More than two months have passed since the James Webb Space Telescope began full-scale scientific observations.
Of the data collected by the web, only a small proportion of the images are actually released to the public. However, it is surprising that images that could not be confirmed in previous space telescopes such as Hubble, Spitzer, and Voyager have been revealed one after the other.
◇ Capture of ‘Neptune’ ring 33 years after Voyager 2
On the 21st (local time), the National Aeronautics and Space Administration (NASA) revealed four rings of Neptune, the eighth outermost planet in the solar system, photographed by Webb. Two of these are the first rings of Neptune to be captured by space telescopes in 33 years since Voyager 2 took several hours of images on its way out of the solar system in 1989.
This is the first time that Neptune’s rings have been observed in infrared light. The web’s strong infrared probing ability has captured the faint dust of Neptune billions of miles away, as sharply as Voyager 2, taken at 4950 kilometers.
When it comes to planets with rings, most people think of Saturn, but Jupiter, Uranus and Neptune also have rings. However, it is very thin and faint, making it difficult to observe. Previously, Hubble had also photographed some of Neptune’s rings, but it did not show the full picture as clearly as the Web.
First discovered in 1846 by the British astronomer William Russell, Neptune is said to be as dark as a sunset even at noon because it orbits the sun every 164 years at a distance that is 30 times the distance from the sun to the earth, which the sun cannot do. arrived fine.
Unlike the blue pictures taken by Voyager 2 or Hubble, the pictures on the web are more grey-white. In fact, Neptune is covered in methane and has a blue color, but why is the color captured differently on the web? This is because the web was filmed with a near-infrared camera (NIRCam, 0.6 to 5 microns). Neptune’s methane gas reflects visible (blue wavelength) light from Hubble and Voyager 2, but absorbs the red color of infrared light emitted by the web.
Bright dots can be seen in the image, which planetary physicist Patrick Irwin explains could represent clouds of methane ice formed at high altitudes. The faint line at Neptune’s equator may be a sign of strong atmospheric circulation from the storm. However, only scientists can guess this.
Neptune’s first moon, Triton, can be seen in the background. The reason it looks brighter than Neptune is because Triton is covered in nitrogen and reflects about 70% of sunlight. Triton uniquely rotates in the opposite direction to Neptune’s rotation. Based on this, astronomers speculate that Triton was originally a celestial body in the Kuiper Belt, but was drawn to the gravitational force of Neptune early in the solar system’s history.
It only took the Web a few minutes to capture Neptune, and 20 minutes to capture the entire picture. In it, Webb captured 7 of Neptune’s 14 moons (Triton, Galatea, Naiad, Thalassa, Despina, Proteus, and Larissa).
“This is the first time we have seen Neptune’s dust rings in infrared light,” said NASA scientist Heidi Hammel.
On the other hand, the reason why Webb is scientifically observing the ‘ice planets’ Neptune and Uranus is that, unlike the ‘giant gas planets’ Jupiter and Saturn, they are far from the sun, are small in size, and contain less hydrogen and helium inside. Astronomers want to study the relationship between atmospheric circulation patterns and weather by comparing icy and gaseous planets.
◇ Mars is the closest planet to Earth. Can you find traces of methane?
Water ban, ‘Maw’, ‘Mok, Thunder’. Mars is the closest exoplanet to Earth. It is also a place that has already made a lot of progress by sending numerous probes from Earth.
What if we looked at Mars on the web? The European Space Agency (ESA) released data from Mars observed by Webb using a near-infrared camera (NIRCam) on the 5th at the European Planetary Science Congress (EPSC) held in Granada, Spain on the 19th (local time).
In fact, Mars is not a good object for the Web to observe. It was designed to capture light from distant, faint, dark objects to capture the early universe 13.5 billion years ago. As it is the closest to Earth and shines brightly, it is rather difficult to observe.
However, Webb observed Mars from a new perspective. First, NASA revealed two types of near-infrared images: short-wavelength and long-wavelength. The image on the left is for reference, and the two on the right are images taken from the web.
The short-wavelength image (top right) taken of the eastern sphere of Mars illuminated by sunlight, shows the approximately 450 km wide Huygens crater and black volcanic rocks on the Great Sirtis Plains. In the long-wavelength image (lower right), cooling was captured after sunset. The brightest part is where the sun is directly above it, so it has the highest temperature and shines brightly. The northern hemisphere, on the other hand, experiences winter.
The power of planetary observation technology was also confirmed through spectroscopy. Spectroscopy is a technique to determine the chemical composition of planets and atmospheres by using the phenomenon that light is reflected from the surface of a planet and passes through the atmosphere, refracted according to its composition, and that the wavelength is changed .
We have already identified Martian dust and ice clouds, atmospheric components, and surface rock types from this image. In the future, it is expected that additional observations will be able to determine the presence of water and the presence of carbon dioxide and carbon monoxide. In particular, the debate is expected to end by checking whether there are organic compounds such as methane and hydrogen chloride, which may be traces of life.
◇ New ‘Jupiter’ face with clear polar aurora, moons and rings
Last month, NASA released a web image of Jupiter. The data released in July was processed to make it easier to identify. The reason Jupiter’s color is different from the previously published appearance is because the image captured by the web’s red, yellow-green and blue infrared filters has been reconstructed to match the light region visible
In the photo, Jupiter’s ‘Great Red Spot’, as well as the faint rings, and the polar aurora are clearly captured. First, the large spot on Jupiter’s surface, the Great Red Spot, is a huge vortex big enough to fit three Earths. Webb was shown this massive storm in white.
What is particularly special about the pictures on the web is the polar aurora borealis. The red aurora formed above the Antarctic and Arctic atmosphere can be seen, and below, the clouds and fog swirling around the poles in yellow and blue.
A lion’s ring of only one millionth the light of Jupiter and two small moons (Amalthea and Adreas) were also captured. Another moon’s shadow and the diffraction spikes produced by Jupiter’s moon ‘Io’ outside the screen also stand out.
“Honestly, I did not expect such a sharp image,” said the NASA team.
Reporter Seo Hee-won (firstname.lastname@example.org)