China is preparing a significant initiative to enhance its astronomical studies and further utilize its space station facility. This ambitious move carries significant prestige for China’s celestial pursuits.
The telescope, named Xuntian, is also referred to as the Chinese Survey Space Telescope or simply CSST. “Xuntian” translates to “heavenly survey” or “exploration of the skies.” With a planned launch for the coming year, the CSST, the size of a bus, contains a primary mirror with a diameter of two meters (6.6 feet).
This ultraviolet-optical space telescope will share its orbit with China’s Tiangong space station. Its main operational lifespan is set at a decade, but there’s potential for extension. The intent behind Xuntian is to surpass the capabilities of NASA’s Hubble Space Telescope.
This massive observatory will orbit close to China’s space station, allowing for periodic maintenance by Chinese astronauts. Lin Xiqiang, vice director of the China Manned Space Agency, revealed that Xuntian aims to achieve significant advancements in areas like cosmology, dark energy and dark matter, the Milky Way and other galaxies, star lifecycle, and exoplanets.
That’s an ambitious goal. Lin mentioned the telescope’s ability to conduct deep-field scans covering 17,500 square degrees and detailed examinations of various celestial entities. Xuntian boasts a camera with 2.5 billion pixels.
Anticipated to be launched into Earth’s orbit next year via a Long March 5B rocket, Xuntian can capture high-resolution universal panoramas. Its resolution is comparable to Hubble, yet it offers a field of view exceeding Hubble’s by over 300 times.
The field of view denotes the sky’s segment a telescope can visualize simultaneously. In a conversation with Xinhua news agency, Li Ran, the project’s chief scientist for the CSST Scientific Data Reduction System, used the imagery of photographing a herd of sheep to underscore CSST’s potential.
Additionally, this powerful telescope will maintain its orbit alignment with the space station, ensuring sustained independent observations. Periodic docking with the space station will allow Tiangong astronauts to supply, service, and upgrade it, as explained by Lin.
Speaking to China Central Television (CCTV), Zhou Jianping, the main architect of China’s manned space efforts, praised Xuntian’s projected capabilities. Zhou also emphasized the telescope’s unrivaled proficiency in generating ultraviolet images among all current global telescope projects.
Li Chengyuan from China’s Sun Yat-sen University’s Physics and Astronomy department noted that while the Chinese Space Station Telescope and Hubble detect similar wavelengths, Xuntian’s field of view is 5 to 8 times broader, a point he highlighted in the Research in Astronomy and Astrophysics journal last year.
The inaugural Xuntian telescope includes five observation tools, such as the main Xuntian module, the terahertz unit, the multichannel camera, the integrated spectrum analyzer, and the exoplanet imaging coronagraph.
Most observation time will be dedicated to the primary Xuntian module, which boasts an expansive viewing field. Typically, the space telescope will operate independently, sharing the same orbit as China’s space station but at a considerable distance.
In the vast domain of pioneering space astronomy, one can cite the achievements of Baltimore’s Space Telescope Science Institute (STScI) as a benchmark. STScI is NASA’s core scientific operation hub and a renowned center for astronomical research.
Located within Johns Hopkins University’s Baltimore campus, STScI oversees renowned projects like the James Webb Space Telescope, and the Hubble Space Telescope, and will command operations for the Nancy Grace Roman Space Telescope set to launch in the mid-2020s.
The Association of Universities for Research in Astronomy operates it on behalf of NASA. While Chinese space authorities are enthusiastic about Xuntian’s potential, certain experts harbor reservations.
Brown, from the limited details available, believes that while China’s Space Station Telescope might offer a broader view than Hubble, it may possess a smaller mirror with reduced collection area and clarity.
Moreover, its spectral clarity might lag behind Hubble’s, and the CSST might not reach the far-ultraviolet spectrum, specifically below 200 nanometers.