Two months after astronomers showed the first photo of the black hole “Sagittarius A*” in the center of the Milky Way, mankind took another step towards exploring the sea of stars.
On July 12th, US Eastern Time, the National Aeronautics and Space Administration (NASA) released the first five images taken by the James Webb Space Telescope. These images cover the frontier research fields of astronomy, such as deep space galaxy clusters, compact galaxy clusters, diffuse nebulae and exoplanets.
These five photos are SMACS 0723 galaxy cluster, Carina nebula, Steven quintuple galaxy, South Ring nebula and exoplanet WASP-96b.
The image of SMACS 0723 galaxy cluster is the deepest and clearest infrared image of the distant universe so far. The near-infrared camera of the Webb telescope took 12 hours to shoot, setting a new record for the Hubble Space Telescope.
SMACS 0723 galaxy cluster contains thousands of galaxies, and the gravitational lens effect caused by its huge mass obviously bends the light of more distant galaxies and forms lens distortion in the center of the image, which is also the most intuitive embodiment of Einstein’s general relativity. In this photo, the Webb telescope even captured an image of 13.1 billion years ago, which is also an early picture of the universe only 1 billion years after the Big Bang.
The Carina Nebula, also known as NGC 3372, is one of the largest diffuse nebulae in the night sky, which is more than four times larger than the famous Orion Nebula and 7600 light years away from the Earth. The most famous objects in the nebula are the bright Star Seamount II (i.e. Carina η) in the southern hemisphere and the keyhole nebula.
The diffuse nebula is also the cradle of the birth of stars. If the nebula, which is essentially composed of thin gas and dust, continues to shrink under the action of gravity and finally successfully stimulates hydrogen fusion, a star embryo-protostar is born. The multi-band study of diffuse nebula is helpful to understand the birth process of star system.
This photo was taken by the Near Infrared Camera (NIRCam) and the Mid Infrared Camera (MIRI) of the Webb Telescope.
The Stephen quintuple galaxy in Pegasus is the most famous dense (quadruple) galaxy group, which is 290 million light years away from the Earth.
The image provided by the Webb Space Telescope has 150 million pixels, providing rich details of this dense galaxy cluster. The gravitational interaction between four adjacent galaxies causes the gas and dust in the galaxy to be thrown out of the galaxy, and the disturbed gas and dust are also the cradle of star birth.
Astronomers predict that this tetrad cluster will eventually merge into a supercluster. The merger process of galaxies is of reference significance to the merger of the Milky Way and Andromeda galaxy in the future. The merger of galactic nuclei also represents the merger of two supermassive black holes in most cases, and it is also a hot spot in gravitational wave research. It has been confirmed that NGC 7319, the brightest galaxy in the four compact galaxy groups, has a supermassive black hole with a mass 24 million times that of the sun.
The Southern Ring Nebula, also known as the Octagonal Nebula, is a planetary nebula located in the constellation Vela, about 2,500 light years away from the Earth.
Unlike diffuse nebulae where stars are born, planetary nebulae are composed of gas and dust shells ejected by stars in their twilight years. The most famous planetary nebula is the crab nebula in Taurus.
The Webb Space Telescope shows more details of the special structure of the southern ring nebula and dust shell in infrared band. For example, two sets of pictures of the South Ring Nebula, the first photo was taken by a near-infrared camera, and the second photo was taken by a mid-infrared camera. In the first photo, only one star can be seen in the center of the nebula, which is a planetary nebula ejected by a twilight white dwarf; The second photo can clearly observe the second star, which is still in the early stage of evolution.
WASP-96 b is one of more than 5000 extrasolar planets in the Milky Way, located in Phoenix, 1150 light years away from the Earth. Although it has been confirmed that it is a gas giant planet with half the mass of Jupiter, it is impossible to have life like Earth. However, through this image, the Webb telescope demonstrated its excellent ability to analyze the atmospheric spectrum of exoplanets.
Weber telescope carried out the most detailed near-infrared transmission spectrum of WASP-96 b atmosphere by carrying a near-infrared imager and a slit-less spectrometer (NIRISS), in which the evidence of water in the atmosphere was clearly found. The Webb telescope also has the spectral analysis ability for other key molecules such as oxygen, methane and carbon dioxide. In the next service life, the Webb telescope will do more spectral analysis on gas giants, terrestrial planets and ice giants.
The Webb Space Telescope is the most expensive and advanced space telescope built in human history. The telescope was officially funded by NASA, European Space Agency (ESA) and Canadian Space Agency (CSA) in 2005. It cost $10 billion before and after, and was finally launched into orbit by ESA in Christmas 2021. On January 24 this year, it successfully entered the orbit near the second Lagrangian point of the Sun-Earth system. Its main mirror is 6.5 meters in diameter, and consists of 18 hexagonal lenses, and is equipped with 5 layers of expandable sun visor.
As the successor of the famous Hubble Space Telescope and Spitzer Space Telescope, Weber Telescope undertakes many tasks such as studying the formation and evolution of the first generation of stars and galaxies after the Big Bang, the formation of star and planetary systems, and exoplanets.