(B)
Are we alone? What's out there? Looking up at the stars, people have always wanted to learn more about space, and scientists have been working hard to find the secrets of the universe(宇宙). Here we're going to go through a timeline of the important moments of space exploration.

Georges Lemaitre first suggested the Big Bang Theory. NASA sent the Hubble Space Telescope. China began to use FAST. China sent Shenzhou 21.
What is the Big Bang Theory? The Big Bang Theory is an idea about how our universe began. Many scientists believe that everything in the universe was pressed(压)together and then it separated into smaller pieces very quickly about 14 billion years ago to create the universe. The Big Bang is thought to be the beginning of everything in the universe.
What is the Hubble Space Telescope(望远镜)? The Hubble Space Telescope was put into space in 1990. Hubble is as long as a large school bus and it weighs as much as two elephants. In order to stay above the atmosphere(大气层), it travels around the Earth at about 5 miles a second. Hubble is able to get clear pictures of faraway stars. A picture called "Hubble Ultra Deep Field" shows some of the farthest galaxies(星系). Pictures from Hubble help scientists learn more about the universe.
What is FAST? China's Five-hundred-metre Aperture Spherical Telescope is known as FAST. It is in Guizhou, China, and has been used since 2016. Scientists can use it to search for signals(信号)of communication that are not coming from the Earth.
What are Shenzhou manned spaceships? They mark the development and achievements of China's space exploration. Since China sent the Shenzhou 1 in 1999, China has made great progress in this field. In 2025, Shenzhou 20 and Shenzhou 21 manned spaceships were sent into space.
(
) 4. The Hubble Space Telescope can help scientists study the universe because
.
A. it is long and heavy enough
B. it takes clear photos of space
C. it can move 5 miles a second
D. it travels far away from some galaxies
(
) 5. What is the best title for the passage?
A. Space Exploration: Searching for Life in Space
B. Space Exploration: Exciting Moments of China
C. Space Exploration: A Better Future for Scientists
D. Space Exploration: Great Progress Humans Made
(
) 6. What is the right structure of the passage?
