The universe is a mysterious place. It fuels our infinite imagination about other worlds, and these mysteries of the universe are portrayed through media such as movies and dramas. In addition, the media has given people the expectation that the mysteries can be real. Responding to this interest, the U.S. began releasing some photographs of space taken by the National Aeronautics and Space Administration (NASA) on July 12, showing the possibility that previous expectations could materialize. The information about the universe provided by the photographs prompts those who have only thought of it as a fantasy until now to think 'maybe it could happen' or 'no way'.
A new paradigm from the JWST
The study of space has been going on for a long time. When the first satellite Sputnik 1 was successfully launched by the former Soviet Union on October 4, 1957, space exploration became a subject of much attention. After that, as Apollo 11 was able to obtain research on other planets, people can research the galaxies or evidence of theories about the universe. In space research, the universe could be seen in person beyond mere theory. According to the report, space telescopes used to see space were at the center of the study. As scientists began to use information from space observations, it became important to determine how to best observe the universe. However, taking pictures on Earth could not give the best information because it was obscured by clouds or unnecessary light sources. To solve this problem, they took the telescope into space and took pictures while in space. The Hubble Space Telescope was launched by NASA on April 24, 1990. It can take pictures of higher quality than those taken on Earth. Until now, the universe around Earth has been observed as useful information for space research. However, a second version of the Hubble Space Telescope was planned because scientists needed more data.
Accordingly, on December 25, 2021, the James Webb Space Telescope (JWST) was launched in anticipation of discoveries in space. It is the largest telescope in human history and was named after NASA's former second director. The focus is on the development of technology that can collect seven times as much light as the Hubble Space Telescope. In addition, the technologies are the ability to see into the interior of space dust and to view the wavelengths of light. Through these abilities, JWST was able to see what Hubble had not seen. They hope to find solid evidence to tell the history of the universe and how the universe came to be. In addition, NASA said it is trying to discover the existence of water and Freon gas - essential for life - to support the theory that another species exists in space. In December last year, the international academic journal Nature predicted, "The James Webb Space Telescope will rewrite astronomy by observing the atmosphere of the farthest galaxies and distant planets, and the process of forming stars hidden in space dust."1) This raises the expectation that advanced technology will show a new universe that has never been seen before.
Seeing the world through innovative eyes
Based on previous expectations, NASA first released a photo taken by the JWST on July 12. The galaxy 'SMACS 0723' in the picture is located 13.1 billion light years away, the farthest galaxy ever observed by humans. As the distance of the galaxy determined by light in space increases, the longer it takes for the light to return and determine the galaxy's size, so people are seeing the past now. In other words, the distance of the galaxy from the earth is 13.1 billion light years, and it means that light from 13.1 billion years ago can be seen. This ultimately shows the appearance immediately after the 'Big Bang' that occurred about 13.8 billion years ago. As the video immediately after the creation of the universe was released in high definition, many scientists began to anticipate what further information about the universe the JWST could bring. The JWST can also take much clearer pictures than previous telescopes to observe detailed structures such as gas, dust, and stars contained in the cluster of galaxies. In addition, NASA said it took photos of water, one of the JWST's goals, providing evidence to support the existence of extraterrestrial life. These discoveries are useful in the search for alien life along with studying the early appearance of the universe.
To picture those photos, JWST must have a high-level technology than the Hubble. The Hubble Space Telescope has observed space in wide field for a long time, but as it is specialized in visible light, it had limitations. The JWST, which is specialized in infrared rays, complements the Hubble. The biggest difference between the JWST and the Hubble is that the area of light sensed is different. The difference in the area where the telescope detects light is the wavelength and it greatly affects the observation of objects. According to Doppler's redshift theory, the farther away a celestial body is, the longer the wavelength. In other words, if people use infrared light, people can see more detailed objects located at a distance than visible light because it has a relatively longer wavelength than visible light. Accordingly, the development of technology using infrared makes it possible to see distant objects clearly and it, in turn, leads to a higher-quality image. The JWST boasts a powerful performance that is about 100 times greater than that of the Hubble thanks to its specialized infrared technology. In addition, it is different from previous telescopes in terms of size. The larger the diameter of the reflector, where light is reflected, the lighter can be collected. So, the resolution indicating the delicacy of the picture increases at the same time. The JWST is equipped with a 6.5 m reflector and four pieces of infrared observation equipment. It is known that the area of the reflector is about 6.3 times larger than that of the Hubble Telescope. Thus, the resolution is also superior to that of the Hubble Telescope.
As such, the JWST's technology has increased the number of observable galaxies. However, some say that strict verification is necessary to implement these observations as research results. Professor Nathan Adams of the University of Manchester in the U.K. said, "The JWST's observational ability can capture very long distances, but there are many doubts about the image veracity. Extreme results require close observation and verification by several people."2) Currently, JWST is the most observable telescope, so it is impossible to refute what JWST observes, which requires careful consideration by many experts. The more observations that can change the science of current space research, the more careful judgment must be. For new observations to have the power to change existing studies, they will have to be conducted through strict verification without errors. The JWST's technology alone has some expectations, but there are also some expectations in the method used with Hubble. Moon Hongkyu, head of the space exploration group at the Korea Astronomical Research Institute said, "In the future, NASA is expected to extend Hubble's lifespan as much as possible and use a strategy to operate with James Webb as much as possible."3) There is also an expectation that two telescopes with different observable areas of light will complement each other and that they will be able to see the universe in more detail.
What we should think about it
Concern does not only come from the review of the study. the James Webb Space Telescope is also having problems with its name and technology. In May 2021, four scientists filed a petition to rename the James Webb Space Telescope. The JWST is named after James Webb, former director of NASA's National Aeronautics, has been accused of discriminating against gay employees in NASA when he was director. According to his criminal act, more than 1,000 scientists have signed in solidarity. Finally, many scientists, including the scientific journal Nature, demanded the telescope be renamed due to evidence of his discrimination against sexual minorities being revealed. However, NASA's current director Bill Nelson rejected the petition, saying he had found no reason to change the name of the telescope. In response, astronomer Lucian Walkowitz, one of the four scientists who started the petition, argued, "If Webb deserves credit, his homophobic behavior should also be recognized."4) He further said Webb must take responsibility and admit wrongdoing if he wants to have the honor of having his name on the telescope. In this situation, this case remains unresolved.
Scientists also have concerns about the JWST's technology. As stated above, the JWST mainly uses infrared cameras, unlike previous space telescopes. This creates a weakness since while allowing people to see what people haven't seen before because it is specialized in infrared observation, the JWST cannot observe multiple angles. There is a clear difference between looking at the universe through a range of wavelengths and just one. This means that the JWST cannot acquire a large array of information. In addition, NASA moved the JWST to the second Lagrange point (L2), 1.5 million kilometers from Earth, to position it in an optimal area for space observation. This distance has an advantage for observing the universe, but it is too far away for humans to reach. In the case of the Hubble telescope, it was located at a relatively close distance, so it could be repaired in the event of a failure. However, being located at a distance that humans cannot reach, it cannot be repaired when problems arise, losing astronomical sums of money. In fact, between May 23 and 25, a micro-planetary object collided with the JWST five times. NASA said the impact of the collision was greater than expected and more than could have been tested on the ground.5) It was a sign that the problems caused by the collision were bigger than expected before the launch, which raised many concerns.
To find a technical solution, NASA has proposed alternatives to other telescopes in parallel with this. First, they announced their intention to continue using the Hubble telescope with the JWST. Unlike the JWST, Hubble does not specialize in just one category, so it can see space using various angles. Although it may not be able to shoot as high quality as the JWST, it can provide various information and can be repaired because of its proximity. Concerning this, Moon Hongkyu, head of the space exploration group in Korea said, "In the future, NASA is expected to extend the life of the Hubble telescope and use a strategy to operate with the JWST as much as possible."6) It is predicted that together they will have the ability to observe both UV, visible, and infrared rays. In addition, he also said that Hubble and the JWST will complement each other's strengths and weaknesses. If this happens, on the one hand, people can look at things that the clear universe using infrared rays which have not yet been revealed. In other words, if the JWST is used for advanced purposes rather than as a replacement for Hubble, much information about space research can be found. the universe viewed through the Hubble and the JWST is expected to provide information that can change space research up to now.
The result will change the world
JWST provided the possibility that many scientists could prove existing predictions and theories and open up paradigms of other research. However, there are some concerns, such as the name of the telescope and technical loopholes. Some scientists stress that NASA should take appropriate steps to solve these problems. Nevertheless, space research is highly valuable in terms of science and technology, so discussions are needed to properly utilize it.
1) Kim Woohyun, "A New Eye for Humanity… 'James Webb Space Telescope'", Electronic Times, February 14, 2022
2) Kwak Nopil, "'The Oldest Light' Met Three Times in A Month...James Webb Revolution", The Hankyoreh, August 8, 2022
3) Lee Jungho, "The James Webb Telescope, Looking Only at the Infrared Rays… Can It Find Extraterrestrial Life?", The Kyunghyang Shinmun, July 12, 2022
4) Kim Hyunki, "[Global] Next Generation Space Telescope, Will It Change Its Name? Evidence of James Webb's Repression of Sexual Minorities Has Come Out", Tech M, April 9, 2022
5) Cho Seunghan, "'James Web' Collides With a Meteoroid Before It Even Goes Into Space Telescope Operation... Adjust the Primary Mirror to Maintain Functions", Donga Science, June 9, 2022
6) See Footnote 4
Jung Nam Chaehee / Reporter
smt_nch@sookmyung.ac.kr
Kim Jang Yunsun / Reporter
smt_jys@sookmyung.ac.kr