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NASA to Return to Venus with Two New Missions

The U.S. space agency NASA has announced plans to launch two new missions to the planet Venus.

The missions will mark a return to U.S. exploration of Venus after many years. Two new robotic spacecraft are to be designed and built to study the planet with the highest temperatures in our solar system.

NASA chose American company Lockheed Martin to create and operate both spacecraft. The company will receive $500 million for each mission through NASA's Discovery Program. The spacecraft are expected to launch between 2028 and 2030.

One mission, called DAVINCI+, is designed to measure the planet's dense¹, cloudy atmosphere to understand how it formed and developed, a NASA statement said. It also aims to capture the first high-quality pictures of geological structures on Venus. Some are similar to ones on Earth.

After arriving at Venus, the DAVINCI+ spacecraft will send a probe into the planet's atmosphere. It will then use its instruments to measure levels of gases and other elements, temperature and pressure, Lockheed Martin said.

The other mission, VERITAS, will map the surface of Venus to learn about "the planet's geologic² history and understand why it developed so differently than Earth," NASA said. When the VERITAS orbiter arrives at Venus, it will use a method called "aerobraking" to place itself "into an optimal³ science position in the planet's orbit," Lockheed Martin said. It will then use imaging equipment to capture data about the planet's geology.

Venus is Earth's closest planetary neighbor and the second closest planet to the sun. It is similar in structure to Earth, but a little smaller. Venus rotates in the opposite direction as Earth and most other planets. Also, its rotation⁴ is very slow.

The air on Venus is so dense and pressurized that it behaves more like a fluid than a gas near the surface. The planet has extremely high winds that push clouds completely around the planet every five days.

Such extreme conditions make it difficult for spacecraft to survive in Venus' atmosphere or on its surface. But scientists are very interested in learning more. Some believe Venus may have had ancient seas that could have made it habitable before unknown forces destroyed them.

"It is astounding⁶ how little we know about Venus," NASA scientist Tom Wagner said in a statement. He added that the new missions can provide fresh data on the planet's thick atmosphere, which is made up mostly of carbon dioxide. "It will be as if we have rediscovered the planet," Wagner said.

James Garvin is the chief scientist for NASA's Goddard Space Flight Center in Maryland. He said in a statement he considers Venus important to understanding "climate change, the evolution of habitability and what happens when a planet loses a long period of surface oceans."

The first spacecraft to explore Venus was NASA's Mariner⁷ 2 in 1962. It passed within about 34,000 kilometers of the planet. NASA says Mariner 2 successfully recorded the planet's temperature for the first time. It measured the Venus surface temperature to be about 465 degrees Celsius⁸.

The United States and the former Soviet⁹ Union sent several spacecraft to Venus from the 1960s to the 1980s. The former Soviet Union is the first and only country to successfully land a spacecraft on the surface of Venus. The first landing was the Soviet explorer Venera 7 in 1970. The Soviet spacecraft lasted less than two hours in the extreme environment.

In 1989, NASA used a space shuttle to send its Magellan spacecraft into orbit around Venus. The European Space Agency also put a spacecraft into orbit around Venus in 2006. And, a Japanese spacecraft called Akatsuki was launched in 2010 and is currently orbiting Venus.

Words in This Story

mission – adj. a flight by an aircraft or spacecraft to perform a specific task

geology – n. the study of rocks and soil and the physical structure of the Earth

probe – n. a vehicle used to examine or observe something closely

optimal – adj. the best of most effective possible in a particular situation

rotate – v. to turn or cause something to turn in a circle

habitable – adj. able to support life

astound⁵ – v. to surprise of shock someone very much

evolution – n. a gradual process of change and development

1 dense   

a.密集的，稠密的，浓密的；密度大的

参考例句：

• The general ambushed his troops in the dense woods. 将军把部队埋伏在浓密的树林里。
• The path was completely covered by the dense foliage. 小路被树叶厚厚地盖了一层。

2 geologic   

adj.地质的

参考例句：

• The Red Sea is a geologic continuation of the valley.红海就是一个峡谷在地质上的继续发展。
• Delineation of channels is the first step of geologic evaluation.勾划河道的轮廓是地质解译的第一步。

3 optimal   

adj.最适宜的；最理想的；最令人满意的

参考例句：

• What is the optimal mix of private and public property rights in natural resources?私人和国家的自然资源产权的最适宜的组合是什么？
• Optimal path planning is a key link for the sailing contest.帆船最优行驶路径规划是帆船比赛取胜的关键环节。

4 rotation   

n.旋转；循环，轮流

参考例句：

• Crop rotation helps prevent soil erosion.农作物轮作有助于防止水土流失。
• The workers in this workshop do day and night shifts in weekly rotation.这个车间的工人上白班和上夜班每周轮换一次。

5 astound   

v.使震惊，使大吃一惊

参考例句：

• His practical grasp of affairs and his energy still astound me.他对事物的实际掌握和他充沛的精力实在使我惊异。
• He used to astound his friends with feats of physical endurance.过去，他表现出来的惊人耐力常让朋友们大吃一惊。

6 astounding   

adj.使人震惊的vt.使震惊，使大吃一惊astound的现在分词)

参考例句：

• There was an astounding 20% increase in sales. 销售量惊人地增加了20%。
• The Chairman's remarks were so astounding that the audience listened to him with bated breath. 主席说的话令人吃惊，所以听众都屏息听他说。 来自《简明英汉词典》

7 mariner   

n.水手号不载人航天探测器，海员，航海者

参考例句：

• A smooth sea never made a skillful mariner.平静的大海决不能造就熟练的水手。
• A mariner must have his eye upon rocks and sands as well as upon the North Star.海员不仅要盯着北极星，还要注意暗礁和险滩。

8 Celsius   

adj.摄氏温度计的，摄氏的

参考例句：

• The temperature tonight will fall to seven degrees Celsius.今晚气温将下降到七摄氏度。
• The maximum temperature in July may be 36 degrees Celsius.七月份最高温度可能达到36摄氏度。

9 Soviet   

adj.苏联的，苏维埃的；n.苏维埃

参考例句：

• Zhukov was a marshal of the former Soviet Union.朱可夫是前苏联的一位元帅。
• Germany began to attack the Soviet Union in 1941.德国在1941年开始进攻苏联。