VOA科学技术2024--SpaceX to Build Vehicle to Deorbit Space Station

The U.S. space agency NASA has chosen SpaceX to produce a vehicle to take the International Space Station (ISS) out of orbit at the end of its service life.

NASA recently announced that SpaceX will design, develop, and build the spacecraft. The vehicle will aim to guide the ISS through a final reentry into Earth's atmosphere. NASA calls the spacecraft the U.S. Deorbit Vehicle. The agency said the deorbiting operation will take place sometime after the station's "operational life," which has been set for 2030.

NASA said its contract with SpaceX to build the deorbit vehicle was worth $843 million. This does not include costs to launch the vehicle. The agency said the launch would be part of a future contract.

California-based SpaceX has an existing relationship with NASA. The company has established itself as a dependable private partner of the agency since 2020. Since then, SpaceX has made regular trips to carry astronauts and supplies to the ISS.

NASA announced last year it had decided¹ on a plan to deorbit the ISS after service ends in 2030. The agency and its international partners agreed that the orbiting laboratory would one day reach the end of its technical lifetime. The station has been continuously inhabited since November 2, 2000.

In a statement, NASA said it chose the method of deorbiting with a specially² designed vehicle to provide a "safe and responsible deorbit of the ISS in a controlled manner."

The space agency did consider other choices, or options, to retire the ISS. One option would have involved the use of several Russian spacecraft in a deorbiting operation. Another plan called for taking apart the space station in space and transporting its pieces back to Earth. Still another option was to move the ISS to a higher orbit, where it would remain out-of-service.

But NASA officials have said none of those options met the agency's requirements for safety and effectiveness. The agency noted³ that while SpaceX will develop the deorbit spacecraft, NASA "will take ownership after development and operate it throughout its mission."

Neither NASA nor SpaceX have provided further information about the planned deorbit vehicle. But Bill Spetch, a leader of NASA's ISS program, recently spoke⁴ to reporters about it. He said the current plan is for the deorbit vehicle to be based on the design of SpaceX's Dragon spacecraft.

Versions of the Dragon spacecraft have been used to carry astronauts and supplies to the ISS. Spetch noted that while the new deorbit vehicle would be based on Dragon, its design would require "some modifications⁵ and changes."

Ken⁶ Bowersox is associate administrator⁷ for Space Operations at NASA's Mission Directorate in Washington D.C. He said in a statement that having a deorbit vehicle "will help NASA and its international partners ensure a safe and responsible transition in low Earth orbit at the end of station operations."

Bowersox noted that although the current ISS cannot continue forever, it will remain "a blueprint⁸ for science, exploration, and partnerships⁹" until its service ends in 2030.

Once the ISS is retired¹⁰, NASA plans to use privately¹¹ developed space laboratories for its space research needs. The agency has already chosen several American companies to develop future space stations.

NASA has said a deorbiting operation would begin by slowing lowering the ISS' altitude level. Officials have said this will likely be carried out by the ISS and its systems without the need for additional spacecraft.

But the final part of the operation is reentry. This will require guiding the ISS into Earth's atmosphere to a target in an unpopulated area of the ocean.

The targeted landing spot has been identified as a place called Point Nemo in the South Pacific Ocean. This is a stretch of open water between New Zealand and the southernmost part of South America. The U.S. National Ocean Service identifies Point Nemo as the point in the ocean that is farthest from land.

NASA predicts that most ISS equipment will burn up or vaporize during the intense heat of atmospheric¹² re-entry. But it says some dense¹³ or heat-resistant elements are expected to survive and land in the ocean.

Words in This Story

inhabited -adj. describing a place where people live

modify - v. to change something in order to improve it

transition - n. a change from one system or method to another, often a slow one

blueprint - n. a plan that shows how someone will design, build or achieve something

altitude - n. the vertical¹⁴ distance of an object above a given level (as sea level)

vaporize - v. to turn, or cause something to turn, from a solid or liquid state into gas

1 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

2 specially   

adv.特定地；特殊地；明确地

参考例句：

• They are specially packaged so that they stack easily.它们经过特别包装以便于堆放。
• The machine was designed specially for demolishing old buildings.这种机器是专为拆毁旧楼房而设计的。

3 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

4 spoke   

n.（车轮的）辐条；轮辐；破坏某人的计划；阻挠某人的行动 v.讲，谈（speak的过去式）；说；演说；从某种观点来说

参考例句：

• They sourced the spoke nuts from our company.他们的轮辐螺帽是从我们公司获得的。
• The spokes of a wheel are the bars that connect the outer ring to the centre.辐条是轮子上连接外圈与中心的条棒。

5 modifications   

n.缓和( modification的名词复数 )；限制；更改；改变

参考例句：

• The engine was pulled apart for modifications and then reassembled. 发动机被拆开改型，然后再组装起来。 来自《简明英汉词典》
• The original plan had undergone fairly extensive modifications. 原计划已经作了相当大的修改。 来自《简明英汉词典》

6 ken   

n.视野，知识领域

参考例句：

• Such things are beyond my ken.我可不懂这些事。
• Abstract words are beyond the ken of children.抽象的言辞超出小孩所理解的范围.

7 administrator   

n.经营管理者，行政官员

参考例句：

• The role of administrator absorbed much of Ben's energy.行政职务耗掉本很多精力。
• He has proved himself capable as administrator.他表现出管理才能。

8 blueprint   

n.蓝图，设计图，计划；vt.制成蓝图，计划

参考例句：

• All the machine parts on a blueprint must answer each other.设计图上所有的机器部件都应互相配合。
• The documents contain a blueprint for a nuclear device.文件内附有一张核装置的设计蓝图。

9 partnerships   

n.伙伴关系( partnership的名词复数 )；合伙人身份；合作关系

参考例句：

• Partnerships suffer another major disadvantage: decision-making is shared. 合伙企业的另一主要缺点是决定要由大家来作。 来自英汉非文学 - 政府文件
• It involved selling off limited partnerships. 它涉及到售出有限的合伙权。 来自辞典例句

10 retired   

adj.隐退的，退休的，退役的

参考例句：

• The old man retired to the country for rest.这位老人下乡休息去了。
• Many retired people take up gardening as a hobby.许多退休的人都以从事园艺为嗜好。

11 privately   

adv.以私人的身份，悄悄地，私下地

参考例句：

• Some ministers admit privately that unemployment could continue to rise.一些部长私下承认失业率可能继续升高。
• The man privately admits that his motive is profits.那人私下承认他的动机是为了牟利。

12 atmospheric   

adj.大气的，空气的；大气层的；大气所引起的

参考例句：

• Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
• Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。

13 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。

14 vertical   

adj.垂直的，顶点的，纵向的；n.垂直物，垂直的位置

参考例句：

• The northern side of the mountain is almost vertical.这座山的北坡几乎是垂直的。
• Vertical air motions are not measured by this system.垂直气流的运动不用这种系统来测量。