Astronomers said that the Sky Survey Telescope, which will co orbit with the Chinese space station in the future, will become a flagship space astronomy facility. It is expected to see the stars and the sea wider, deeper and clearer, which is expected to promote the leap forward development of China’s Optical Astronomy and bring mankind a revolutionary understanding of the universe.
Liu Jifeng, deputy director of the National Astronomical Observatory of the Chinese Academy of Sciences and director of the Joint Center for Telescope Science of the Chinese space station, told reporters that the Chinese space station telescope expected to be launched in 2023 is very powerful. It is the size of a bus and stands three stories high. Its aperture is two meters, which is equivalent to that of the US Hubble Space Telescope, and its field of view is 350 times larger than that of the Hubble Space Telescope.
“The field of view is the field of view that the telescope can see the universe. The field of view of the Hubble telescope is about 1 / 100 the size of a fingernail after we straighten our hands. It has observed the universe for 30 years, but all its data account for only a small part of the night sky.” Said Li Ran, a scientist responsible for telescope scientific data of China space station.
“Our telescope is very suitable for Sky Survey and can complete large-scale cosmic observation relatively quickly.” Zhan Hu, a scientist responsible for the optical facilities of the telescope survey of the Chinese space station, said.
Zhan Hu, who has been involved in the project for more than ten years, said that the telescope was originally designed to be placed on the Chinese space station, but such observation will be limited. The final plan is to fly independently in the same orbit with the space station. It carries its own fuel and can be connected with the space station for replenishment, maintenance and equipment upgrading when necessary. Its planned mission life is 10 years, which can be continuously extended through maintenance.
He said that from the current global planning, from 2025 to 2035, the Chinese space station telescope may be the most capable Space Survey Telescope in the near ultraviolet to visible light band of its work, and its design indicators are world leaders in many aspects.
“At present, although China is already a large Aerospace country, the development of space astronomy is still relatively lagging behind. This telescope is a very rare opportunity for Chinese scientists. We hope it can bring exciting discoveries and achieve a breakthrough in human cognition of the universe.” Zhan Hu said.
Zhan Hu introduced that the telescope adopts an off-axis optical system and is equipped with five first generation observation instruments, including sky survey module, terahertz module, multi-channel imager, integral field of view spectrometer and extrasolar planet imaging coronal instrument.
Li Ran said that the detector of the Hubble telescope camera is the size of a palm of the hand, while the main focal plane of the China Space Station telescope sky survey module is composed of 30 detectors, each of which is larger and has more pixels than the Hubble detector. After operation, it will become the largest camera in space.
“It’s like a flock of sheep on the mountain. Hubble can see one of them. We can photograph tens of thousands of sheep, and each one is as clear as Hubble can see.” Li Ran said.
He said that as the most expensive space astronomy facility in China, its main task is to help answer the most basic questions of the universe, such as what dark matter and dark energy are and how galaxies evolve, so as to help humans understand the universe. It will take pictures of more than 40% of the night sky, which is equivalent to cutting back a piece of the universe and putting it on the earth. These images will be digitized and produce a very large amount of data, which can be used by scientists all over the world to carry out research.
The China Space Station telescope will help astronomers observe more than 1 billion galaxies, determine the location, shape and brightness of these galaxies, and map the structure and evolution of the universe.
“We already know that the universe is expanding, and we can also measure the current expansion rate. But does the expansion rate of the universe change, and what exactly supports the expansion of the universe? This is one of the key problems in physics today. Astronomers will study the evolution of matter in the universe through the telescope of the Chinese space station to measure the expansion history of the universe, which is expected to unveil the veil of the frontier of new physics.” Li Ran said.
It can also help astronomers map nearly 10 billion light-years of dark matter to speculate what dark matter is and answer another basic problem of the universe.
In addition, the telescope can also test whether general relativity is still valid on the cosmic scale, limit the upper limit of neutrino mass, and help humans understand the initial state of the universe.
“It can also do a lot of very interesting observation and research. For example, it can draw an accurate galactic dust map, observe how supermassive black holes devour matter, photograph and study faint exoplanets through high contrast direct imaging, and it is possible to find new special celestial bodies.” Zhan Hu said.
“It can also observe the big planets in the solar system. For example, Uranus has not been observed by an orbit detector. Its orbit cycle is more than 80 years, and the Hubble telescope has been monitored for many years. After the Chinese space station telescope is launched, the Hubble telescope may no longer work. Therefore, if humans want to know how Uranus is in a complete orbit cycle, China can contribute this knowledge.” Li Ran said.
Such a versatile space telescope has basically attracted the whole Chinese astronomical community.
“Chinese astronomers have never had such good instruments in the optical band. This telescope will bring Chinese optical astronomy to the forefront of the world, get the opportunity to make important contributions, and train a generation of world-class scientists for China. It will bring very beautiful pictures of the universe, enable ordinary people to truly feel and understand the universe, and will have a great impact on society.” Li Ran said.
It is reported that China Aerospace Hi-Tech Holding Group Co.Ltd(000901) group and a number of scientific research institutions of the Chinese Academy of Sciences participated in the construction of the telescope. Manned Changzheng Engineering Co.Ltd(603698) relies on the telescope science work joint center established by the National Astronomical Observatory to organize scientific research and develop scientific data processing system.
