n July 2022, the first images from the James Webb Space Telescope (JWST) were released, causing a sensation. Infrared photos showed planets, stars and galaxies in unprecedented detail, going viral online and still making headlines around the world.
With interest in science and astronomy at a high, we hosted an International Deep Space Dialogue at the Tencent WE Summit 2022. Now in its 10th year, the Summit serves to highlight the most ambitious scientific work being done around the world.
Distinguished speakers for this dialogue included Nobel Prize laureate Dr. John C. Mather, Senior Project Scientist at the JWST; Dr. Zhan Hu, Project Scientist for the Optical Facility of the Chinese Space Station Telescope (CSST), Chinese Academy of Sciences; and Dr. Deng Dafu, Deputy General Manager of Tencent IEG Cros and AI expert for the CATCH program.
In the spirit of collaboration that underpins the Summit, this is the first dialogue among the three programs. Joining them was a student and amateur astronomer Zhou Zezhen, winner of the young category of Astronomical Photographer of the Year by the Royal Observatory Greenwich.
The dialogue was moderated by Prof. Gou Lijun, a research fellow at NAOC.
Diverse Space Programs, Complementary Missions
The JWST, with a diameter of 6.5m, is the largest optical telescope in space. Launched on December 25, 2021, the telescope is a joint project involving 20 countries, and uses infrared photography to study light from distant universes. Dr. Mather says that “it is observing everything, from the first stars and galaxies and black holes to planets in the solar system.”
Scheduled for launch in the next year or two will be the CSST – a two-meter aperture-wide field space telescope – into the same low earth orbit as that of the Space Station. Dr. Zhan explains that the CSST’s primary mission is “to carry out high-resolution, large area multiband imaging and spectral surveys using a camera that will be the largest one in space.”
Meanwhile, CATCH will launch a fleet of smart satellites outfitted with X-ray telescopes to observe multiple space phenomena such as black holes, neutron stars, gamma ray bursts and supernovas. The satellites use AI calculations to make observations, and notify other satellites in the fleet to watch a target around the clock if something of interest is picked up.
Frontier Technology Brings Complex Challenges
Building the JWST presented unique challenges that took years to overcome. Dr. Mather describes it as an “origami telescope” because of the way it had to be folded for launch. The engineering was “extremely ambitious” and required the development of 10 new technologies to focus the telescope after launch, piece the telescope together out of 18 hexagons, ensure the sunshades worked, and invent new kinds of infrared detectors.
“We had to design it, build it and test it, and when it didn’t work, had to start all over again. Finally, after four tests, it worked,” says Dr. Mather.
For the yet-to-launch CSST, the project team is working to finalize mission parameters. They have not yet determined which celestial objects will be observed and how to disseminate the vast quantity of data that will be collected. According to Dr. Zhan, CSST is mainly a survey telescope. It can be used for observing nearby galaxies such as M31, a very beautiful and large galaxy, and nearby dwarf galaxies as well as galaxy clusters. Similar to the JWST, the CSST can use galaxy clusters to study strong lensing effects, and Zhan’s team expects to get more solid observations next year.
CATCH uses reinforcement learning to help AI solve longstanding conundrums. However, it must first conduct intensive testing to overcome high training and deployment costs, limited interpretability and the lack of learning, historical experience and data that is the foundation of algorithms.
Going Where No Human Has Gone Before
Each project solves problems and uses technology that allows astronomers to see and do things for the first time and learn about things that have long puzzled humanity.
The JWST uses infrared so it can see the most distant universes, or objects that are too cool to emit visible light, and inside clouds of glowing gas and dust where stars are born.
This allowed the JWST team to observe planets around other stars, and learn that some planets have water vapor in their atmosphere. They have observed black holes and star-forming regions, including the spectacular Carina Nebula.
Compared to ground telescopes, the CSST will have the advantage of high angular resolution and wavelength coverage, along with a large area of sky coverage of one square degree. It may not sound like much, but gives CSST a high-resolution field of vision that is 10,000 times greater than an optical ground telescope.
We know that game technology has real world applications. Now we can see how it can help deep space exploration. The CATCH project uses game AI developed by Tencent Games to help satellites estimate the space environment and carry out observations in an intelligent, coordinated manner. It does so by treating celestial objects as agents, and applies corresponding algorithms to find an optimal solution.
A Platform For the Next Generation of Scientists and Astronomers
Zhou Zezhen, a Chinese middle school student, displayed a sound grasp of astronomy and asked probing questions of the senior panel. He directed a question to Dr. Mather about how the JWST studies black holes, dark matter and dark energy, given they are effectively invisible.
Dr. Mather replied that the JWST can detect their presence through gravitational effects. The gravity of galaxies bends light, indicating the presence of dark matter, which is deduced rather than observed, allowing us to know about faraway galaxies.
Astute questions were also directed at Dr. Zhan about the advantages of the CSST compared to existing ground telescopes, and to Dr. Deng about how he came up with the idea to apply game AI to a space mission and how to train the AI for such a mission.
Making an Impact and Helping Scientific Development Through Ideas Exchange
With the launch of CSST on the horizon, Dr. Zhan and other scientists were keen to hear insights from Dr. Mather about how to maximize the impact of the project and the huge investment into getting it off the ground.
Dr. Mather’s response was clear and simple: “share the data and ask for help.” He went on to elaborate that “the more you can publish your data and have other people analyze it, the more interesting it will be.”
He outlined how the effort and skills required to build a telescope or observatory are different from those needed to analyze the data and make interesting discoveries, and the JWST is open to proposals and partnerships from any astronomer or scientist around the world.
Dr. Mather also had a message for young people such as Zhou, saying that astronomers have a wide understanding of physics and engineering, making them highly qualified for scientific and technical fields, especially in data analysis.
He concluded on an optimistic note, reflecting the current enthusiasm for science and astronomy. “It’s a very exciting time to be an astronomer because we have new equipment, which means new discoveries.” With them, “many, many things are possible.”
In addition to this dialogue, the WE Summit 2022 also hosted several dialogues between Chinese teenagers and Thomas Lindahl, Nobel Laureate in Chemistry, and considered the father of DNA repair; Jiang Peng, a researcher at the NAOC and chief designer of China Sky Eye, the Five-hundred-meter Aperture Spherical radio Telescope (FAST); and other scientists. Such discussions have inspired the next generation of students to seek out, think about, and pursue science.
More than 80 of the world’s top scientists have attended the WE Summit over its 10-year history. They have shared cutting-edge scientific and technological information with the public, including theoretical physics, astronomical exploration, brain-computer interface, quantum computing, life science and other fields.