天宫二号上的“定时神针”：3000万年误差1秒

This aerial photo taken on April 5, 2023 shows a view of the Humble Administrator's Garden in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 4, 2023 shows a view by the Jinji Lake in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 3, 2023 shows a view of a historic and cultural block of Pingjiang Road in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 3, 2023 shows an industrial park in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 4, 2023 shows a view in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial panorama photo taken on July 3, 2023 shows the night view of an industrial park in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 4, 2023 shows a view by the Jinji Lake in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 3, 2023 shows a view of a historic and cultural block of Pingjiang Road in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on April 5, 2023 shows people visiting Suzhou Museum in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on April 10, 2023 shows the night view of the Changmen gate in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 4, 2023 shows the Beisi Pagoda in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 3, 2023 shows the night view of an industrial park in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)

This aerial photo taken on July 3, 2023 shows a view of an industrial park in Suzhou, east China's Jiangsu Province. Suzhou, a city with a history of over 2,500 years, is referred to as heaven on earth in a famous Chinese adage. (Xinhua/Li Bo)