Chinese Researchers Consider Rockets to Defend Against Asteroids

Chinese researchers say they believe a group of rockets could be used to change the path of asteroids² that might pass near Earth.

A team at China's National Space Science Center carried out simulations on the proposed asteroid¹ defense³ system.

The scientists said their research suggests 23 rockets of China's biggest kind of rockets could force a large asteroid to change direction. They said the rockets could move the asteroid from its path by a distance of 1.4 times Earth's radius⁴.

Most experts agree that there is only a small likelihood that a large asteroid or other space object will crash into Earth and cause great destruction. However, many organizations do recognize the real risk of such an event.

For example, the U.S. space agency NASA and its international partners continuously search the skies for what scientists call near-Earth objects (NEOs). Such objects include asteroids and comets that come within 50 million kilometers of Earth's orbit.

The Chinese research was based on defending against a specific asteroid, Bennu, which orbits the sun. Bennu is about a half-kilometer wide. It is considered a near-Earth asteroid. NASA says Bennu reaches its closest distance to Earth every six years.

The researchers recently reported on their proposal in a study in a planetary science publication called Icarus.

China's Long March 5 rockets are a central part of the country's space program. They have been used to launch space station elements and carry spacecraft to the Moon and Mars. China has successfully launched six Long March 5 rockets since 2016.

Alan Fitzsimmons is a professor of astrophysics at Queen's University Belfast in Northern Ireland. He told Reuters he finds the idea of using rockets to act as an asteroid deflector "a rather nice concept."

Fitzsimmons continued: "By increasing the mass hitting the asteroid, simple physics should ensure a much greater effect." He added, however, that the actual operation of such a mission needs to be studied further.

Experts have estimated there is about a 1 percent chance that a 100-meter-wide asteroid would strike Earth in the next 100 years, said Gareth Collins. He is a professor at Imperial College London. "Something the size of Bennu colliding is about 10 times less likely," Collins added.

Scientists say deflecting⁵ an asteroid's path presents a lower risk than blasting the rock with nuclear explosives, which may cause it to break into pieces without changing direction.

A similar idea has already developed into a planned NASA mission called the Double Asteroid Redirection Test (DART⁶).

Sometime between late 2021 to early 2022, NASA plans to launch the robotic DART spacecraft to reach the near-Earth asteroid Didymos. NASA considers Didymos a "binary⁷ asteroid system." This means it is made up of a large, main asteroid, and a smaller "moonlet" asteroid.

NASA says when the DART spacecraft arrives at Didymos about a year after launch, it will attempt to crash land on the moonlet. The test seeks to find out how the crash will affect the asteroid's travel path.

Words in This Story

asteroid – n. a rocky object that goes around the sun like a planet

simulation – n. a creation of something that behaves or looks like something real but is not

radius – n. the distance from the center of a circle to its edge

comet – n. an object in space that leaves a bright line behind it in the sky

concept – n. an idea of principle

collide – v. to strike an object

1 asteroid   

n.小行星；海盘车(动物)

参考例句：

• Astronomers have yet to witness an asteroid impact with another planet.天文学家还没有目击过小行星撞击其它行星。
• It's very unlikely that an asteroid will crash into Earth but the danger exists.小行星撞地球的可能性很小，但这样的危险还是存在的。

2 asteroids   

n.小行星( asteroid的名词复数 )；海盘车，海星

参考例句：

• Asteroids,also known as "minor planets",are numerous in the outer space. 小行星，亦称为“小型行星”，在外太空中不计其数。
• Most stars probably have their quota of planets, meteorids, comets, and asteroids. 多数恒星也许还拥有若干行星、流星、彗星和小行星。

3 defense   

n.防御，保卫；[pl.]防务工事；辩护，答辩

参考例句：

• The accused has the right to defense.被告人有权获得辩护。
• The war has impacted the area with military and defense workers.战争使那个地区挤满了军队和防御工程人员。

4 radius   

n.半径，半径范围；有效航程，范围，界限

参考例句：

• He has visited every shop within a radius of two miles.周围两英里以内的店铺他都去过。
• We are measuring the radius of the circle.我们正在测量圆的半径。

5 deflecting   

（使）偏斜， （使）偏离， （使）转向( deflect的现在分词 )

参考例句：

• A variety of mechanical surfaces have been employed for deflecting the exhaust jets of solid-propellant rockets. 人们已经用过各种类型的机械控制面来偏转固体推进剂火箭的排气流。
• If she made a leading statement, he was expert deflecting her into more impersonal channels. 只要她一开口，他就会巧妙地把她的话题转到与个人无关的问题上去。

6 dart   

v.猛冲，投掷；n.飞镖，猛冲

参考例句：

• The child made a sudden dart across the road.那小孩突然冲过马路。
• Markov died after being struck by a poison dart.马尔科夫身中毒镖而亡。

7 binary   

adj.二，双；二进制的；n.双(体)；联星

参考例句：

• Computers operate using binary numbers.计算机运行运用二进位制。
• Let us try converting the number itself to binary.我们试一试，把这个数本身变成二进制数。