VOA科学技术2024--Spacecraft Problems Could Keep NASA Astronauts at Space Station until February

Two American astronauts could remain at the International Space Station (ISS) until February if the spacecraft that transported them cannot be fixed¹ to safely bring them home.

The U.S. space agency NASA said last week it had not yet made return plans for astronauts Butch Wilmore and Suni Williams. The two have been aboard the ISS since June 6.

The American astronauts were expected to stay in space for only a week. But technical issues with the Boeing-built Starliner spacecraft have so far prevented a return trip.

The trip that carried Wilmore and Williams was a test flight for Starliner that marked the first time the spacecraft successfully carried astronauts to space.

NASA looking for a solution

NASA officials held a news conference Wednesday to discuss the ongoing² situation with Starliner and the astronauts at the ISS. They said the agency is still working with Boeing to find a solution for the spacecraft's technical difficulties. Investigations³ have centered on helium leaks and thruster problems with Starliner.

But if those issues cannot be resolved in the coming weeks, NASA said it could decide to use SpaceX's Crew Dragon spacecraft to bring the astronauts back to Earth. NASA has been using SpaceX's Crew Dragon to regularly carry astronauts and supplies to the ISS since 2020.

If NASA decides to use Crew Dragon, it said it would leave two of four seats open during the spacecraft's next planned launch to the ISS in late September. Wilmore and Williams would then make the trip back to Earth with Crew Dragon.

NASA officials told reporters they had brought in additional experts to examine Starliner's leak issues and thruster failures. At the same time, the space agency is looking more closely at SpaceX as a backup solution to get the astronauts back home.

The agency's space operations mission chief, Ken⁴ Bowersox, said NASA's current thinking is that "we could take either path." He added that during a recent meeting, "We heard from a lot of folks that had concern, and the decision was not clear." NASA has said a final decision should be made by mid-August.

Boeing representatives did not take part in the news conference. But the company issued a brief statement Wednesday repeating its position that Starliner could still be fixed to safely transport the astronauts. "We still believe in Starliner's capability⁵ and its flight rationale," Boeing said.

The Boeing statement said if NASA did decide to change Starliner's mission, the company would "take the actions necessary to configure Starliner for an uncrewed return."

Steve Stich is the commercial crew program manager for NASA. He said the agency was not seriously considering launching a separate SpaceX flight to pick up Wilmore and Williams.

Problems with thruster's seals

Officials said tests run by Boeing and NASA on Earth have reproduced Starliner's thruster problems. This has suggested to engineers a possible issue with the thruster's seals. But Stich noted⁶ it was not clear what is causing the seal issues.

The thrusters are important for permitting Starliner to back away from the ISS during its separation operations. At the same time, engineers are seeking to find the cause of helium leaks in the spacecraft's propulsion system. The first leak happened before the launch, but more appeared during flight.

Boeing has faced repeated delays as it struggles to complete NASA's flight testing process before it can receive approval to start running official trips to the ISS.

Words in This Story

thruster - n. an engine that produces propulsion by releasing a jet of fluid or a stream of particles

rationale - n. a group of reasons for a particular decision or belief

configure - v. to arrange something or put its parts together in a particular form or pattern

propulsion - n. a force that pushes something forward

1 fixed   

adj.固定的，不变的，准备好的；(计算机)固定的

参考例句：

• Have you two fixed on a date for the wedding yet?你们俩选定婚期了吗？
• Once the aim is fixed,we should not change it arbitrarily.目标一旦确定，我们就不应该随意改变。

2 ongoing   

adj.进行中的，前进的

参考例句：

• The problem is ongoing.这个问题尚未解决。
• The issues raised in the report relate directly to Age Concern's ongoing work in this area.报告中提出的问题与“关心老人”组织在这方面正在做的工作有直接的关系。

3 investigations   

（正式的）调查( investigation的名词复数 )； 侦查； 科学研究； 学术研究

参考例句：

• His investigations were intensive and thorough but revealed nothing. 他进行了深入彻底的调查，但没有发现什么。
• He often sent them out to make investigations. 他常常派他们出去作调查。

4 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.

5 capability   

n.能力；才能；(pl)可发展的能力或特性等

参考例句：

• She has the capability to become a very fine actress.她有潜力成为杰出演员。
• Organizing a whole department is beyond his capability.组织整个部门是他能力以外的事。

6 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。