VOA科学技术2024--NASA Extends Laser Communication in Space to 226 Million Kilometers

The American space agency NASA has completed a new experiment that sent data over 226 million kilometers in space. The result marks a major improvement over previous tests that measured data transfers over 31 million kilometers.

The method is known as Deep Space Optical Communications (DSOC). The high-speed transfer technology uses lasers to send large data files over very long distances. NASA is looking to the method to improve, or upgrade, existing communication technology.

Traditionally, NASA has depended on radio communications to send data back and forth¹ through space. But this method has a limited bandwidth, meaning at a certain point the system can no longer effectively process data. So, the agency is seeking to use the new method to support new technologies and planned trips to the moon and other places.

NASA officials say the DSOC system will be able to transfer huge amounts of science data through space. This is especially needed for large data files, as well as high-quality images and videos sent from space.

The DSOC system is based on laser technology. Laser communications are also known as optical communications. NASA explains that the technology will permit "up to 100 times more data" to be sent back to Earth than current radio wave systems.

"Much like fiber² optics replacing old telephone lines on Earth as demand for data grows, going from radio communications to laser, or optical, communications will allow increased data rates throughout the solar system," NASA said in a statement.

NASA said the laser system works with signals that exist at near-infrared wavelengths³. Data transferred by laser takes the form of bits - the smallest pieces of data a computer can process. These bits are contained within the laser's photons.

NASA is testing the DSOC on its Psyche⁴ spacecraft. Psyche was launched in October 2023 on its way to observe a mostly metal asteroid⁵. The experiments involved a device aboard Psyche. It was able to send data to and receive data from a telescope in California.

The agency estimates it would take about nine weeks to transmit a complete map of Mars back to Earth with current radio frequency systems. But with a laser-based method, the time would be cut to nine days. Also, laser communications equipment is smaller and requires less energy.

Laser-based communication has already been demonstrated in low Earth orbit and on the moon. But the research team working on the DSOC project said this is the first time the method has been successfully tested in deep space.

Meera Srinivasan is a project leader at NASA's Jet Propulsion Laboratory in Southern California. She said in a statement the system was able to transfer about 10 minutes of data during an experiment on April 8. Srinivasan said the result represented an important new "milestone⁶" for the project.

The asteroid Psyche is traveling to is also called Psyche. It is believed to be made mostly of metal. NASA expects the spacecraft to travel about 3.6 million kilometers over six years to reach the asteroid. Developers of the system say when Psyche is at its farthest point from our planet, the DSOC system's photons will take about 20 minutes to travel back to Earth.

Words in This Story

transfer - v. to send from one place to another

bandwidth -n. the amount of data that can be transferred in a communication channel in a certain period

fiber optics - n. the use of thin, glass or plastic threads that can carry light to carry data, especially with electronic devices

photon - n. a small piece of matter that is a basic unit of electromagnetic energy

asteroid - n. an object made of rock and metal that orbits the sun, but is smaller than planets

milestone - n. an important event that happens during the development or history of something

1 forth   

adv.向前；向外，往外

参考例句：

• The wind moved the trees gently back and forth.风吹得树轻轻地来回摇晃。
• He gave forth a series of works in rapid succession.他很快连续发表了一系列的作品。

2 fiber   

n.纤维，纤维质

参考例句：

• The basic structural unit of yarn is the fiber.纤维是纱的基本结构单元。
• The material must be free of fiber clumps.这种材料必须无纤维块。

3 wavelengths   

n.波长( wavelength的名词复数 )；具有相同的/不同的思路；合拍；不合拍

参考例句：

• I find him difficult to talk to—we're on completely different wavelengths. 我没法和他谈话，因为我们俩完全不对路。 来自《简明英汉词典》
• Sunlight consists of different wavelengths of radiation. 阳光由几种不同波长的射线组成。 来自辞典例句

4 psyche   

n.精神；灵魂

参考例句：

• His exploration of the myth brings insight into the American psyche.他对这个神话的探讨揭示了美国人的心理。
• She spent her life plumbing the mysteries of the human psyche.她毕生探索人类心灵的奥秘。

5 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。

6 milestone   

n.里程碑；划时代的事件

参考例句：

• The film proved to be a milestone in the history of cinema.事实证明这部影片是电影史上的一个里程碑。
• I think this is a very important milestone in the relations between our two countries.我认为这是我们两国关系中一个十分重要的里程碑。