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本月在中国西南部，业余太空观察员拍摄了一个细长的长征3B火箭的视频，这些火箭在一团烟雾和火焰中发射。
测试中可能遇到的词汇和知识：
nascent[ˈnæsnt] adj. 新生的
constellation[ˌkɒnstəˈleɪʃn] n.星座
prestige[preˈsti:ʒ] n.声望
阅读马上开始，建议您计算一下阅读整篇文章所用的时间，对照下方的参考值就可以评估出您的英文阅读水平。
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In south-west China this month, amateur space watchers shot videos of a slender Long March 3B rocket launching in a plume of smoke and flame.
Hours later, China’s state space agency confirmed the launch and revealed the valuable payload onboard: two satellites for BeiDou, China’s nascent global navigation system.
The launch brought the tally of orbiting third-generation BeiDou satellites to 19 — just enough to begin offering navigation services to some allied countries by the end of this year.
Since 2017, China has been rapidly creating a navigational satellite constellation to rival America’s GPS. This year alone, it launched 11 BeiDou satellites, some as few as 17 days apart.
Global commercial coverage is slated for 2020, at which point BeiDou, the name in China for the constellation called the Big Dipper or Plough in the West, will be one of only three global navigation systems in the world.
The project, estimated to cost at least $9bn, is part of China’s ambitions to become a major scientific power. By constructing its own global navigation system, China will have control of a technology that is increasingly vital to how we see the world.
Satellite systems are integral to “anything that needs time and space accurately measured”, said Keith Hayward, former head of research at the Royal Aeronautical Society in the UK. “It’s a living symbol of technological superiority. . . You’re talking of prestige.”
The Global Positioning System developed and operated by the US Air Force remains the most-commercially used navigation system in the world. Other countries have followed suit.
Only Russia’s GLONASS is functionally global as of 2011. This year, the first four of Japan’s QZSS satellites began service while the UK has begun exploring the feasibility of building its own satellite navigation system as it will be locked out of the European Union’s Galileo project after March 2019.
Chinese scientists have made no secret of their ambitions to one day eclipse GPS in both technical precision and international sway. Eventually, BeiDou’s global network will have 35 satellites in orbit, with the highest ratio over the Asia Pacific region for greater accuracy.
“China’s BeiDou is the world’s BeiDou, and the global satellite navigation market is certainly BeiDou’s market,” Yang Changfeng, the system’s chief engineer, told state media last year.
BeiDou’s engineers are looking to best the US in the dimension of time as well. Beyond positioning and navigation, GPS satellites currently set international time and frequency standards.
At the heart of a satellite navigation system is an atomic clock capable of precisely measuring time down to the nanosecond.
One thing China could exploit is giving greater access to BeiDou [to certain nations] than what other countries might get from GPS
Malcolm Davis, Australian Strategic Policy Institute
The clocks are integral to the triangulation method satellites use to determine location. In GPS satellites, they also measure time internationally, keeping global financial markets in sync by standardising and verifying the timing of transactions down to one-billionth of a second.
“Atomic timekeeping is one of the most important things for a navigation system,” said Lan Tianyi, founder of Ultimate Blue Nebula, a private aerospace consultancy. Scientists are now racing to build more precise atomic clocks; this summer, Chinese researchers announced they had maintained a prototype of a more powerful “cold” atomic clock for a record 15 months.
China’s rapidly modernising military, the People’s Liberation Army, also relies on BeiDou. Both GPS and BeiDou contain at least two signal channels. One for commercial use is capable of fixing a location for civilian users precise to 2.5m to 5m; a separate channel several times more exact is reserved exclusively for state and military use, whose encryption codes can be given to allies for use in times of emergency.
For decades, the technical superiority of GPS gave the US unrivalled capabilities in global mapping and location services, expertise it sometimes extends to a small number of Nato allies. China has been exploring a similar arrangement by offering to build ground-equipment bases in Pakistan and south-east Asian nations in exchange for a higher-precision BeiDou service to military and government users there.
“One thing China could exploit is giving greater access to BeiDou [to certain nations] than what other countries might get from GPS,” said Malcolm Davis, a senior analyst at the Australian Strategic Policy Institute, a defence think-tank.
Commercially, a global BeiDou would require companies looking to tap Chinese consumers to adapt to an alternative commercial standard than that of GPS, meaning everything from air-control towers to autonomous vehicles would need to be equipped to receive BeiDou satellite signals.
New models of mobile phones released by mainstream Chinese brands, such as Huawei and Xiaomi, have already been made compatible with BeiDou, as are 4.8m Chinese-made cars, according to People’s Daily, the Chinese Communist party’s official outlet.
Foreign brands have been slower to adopt BeiDou. For example, Apple’s newest iPhone XR and XS do not use BeiDou for their navigation services, instead relying on GPS, Japan’s QZSS, GLONASS and Galileo, raising the ire of Chinese citizens online before their launch in September.
But BeiDou is beginning to make inroads outside of China. In May, alongside US firm Iridium, it was given UN contracts for use with distress signal equipment for the maritime industry, breaking the monopoly British firm Inmarsat commanded for decades.
请根据你所读到的文章内容，完成以下自测题目：
A.China’s new global navigation system
B.America’s GPS
C.Long March 3B rocket
D.China’s state space agency
答案 (1)
A.It will enable China to have control of a vital technology
B.It will bring in a large amount of revenue directly
C.It will help China win the space war
D.It will replace the obsolete GPS
答案 (2)
A.A mirror
B.A laser generator
C.An atomic clock
D.A radio transmitter
答案 (3)
A.BeiDou
B.Iridium
C.Inmarsat
D.Galileo
答案 (4)
(1) 答案：B解释：Hours later, China’s state space agency confirmed the launch and revealed the valuable payload onboard: two satellites for BeiDou, China’s nascent global navigation system.
(2) 答案：A解释：By constructing its own global navigation system, China will have control of a technology that is increasingly vital to how we see the world.
(3) 答案：C解释：At the heart of a satellite navigation system is an atomic clock capable of precisely measuring time down to the nanosecond.
(4) 答案：D解释：But BeiDou is beginning to make inroads outside of China. In May, alongside US firm Iridium, it was given UN contracts for use with distress signal equipment for the maritime industry, breaking the monopoly British firm Inmarsat commanded for decades.