Telescope set to unravel cosmic mysteries

New facility may help provide answers to some of the biggest questions astronomers have long been asking about the universe. Xinhua reports.

The Chinese Survey Space Telescope, also known as the Chinese Space Station Telescope or the Xuntian Space Telescope, is a space-based optical observatory that will allow astronomers to conduct surveys by capturing a general map or images of the sky.

The CSST is a bus-sized facility, whose length is equal to that of a three-story building. Although it has an aperture of 2 meters, a little smaller than the Hubble Space Telescope, its field of view is 350 times larger than Hubble's, according to Liu Jifeng, deputy director at the National Astronomical Observatories of China.

Li Ran, a project scientist at the CSST Scientific Data Reduction System, said, "The field of view is the area of the sky a telescope can see at one time."

Hubble's field of view is approximately 1 percent of the size of a fingernail at an arm's length, thereby the telescope observed only a tiny fraction of the sky, Li added.

The CSST, which is still under construction, has a three-mirror anastigmat design that helps it achieve superior image quality within a large field of view, according to the researchers.

Moreover, it is a Cook-type, off-axis telescope without obstruction that can, in principle, achieve higher precision in photometry, position and shape measurements when properly sampled.

"It has an advantage for survey observations since it can scan a large part of the universe fairly quickly," said Zhan Hu, a project scientist at the CSST Optical Facility.