Join for a Free Newsela Account

It's free to read Newsela. Join and get unlimited access to read every article at every reading level.


Cluttered space: Orbiting debris poses increasing threat, scientists say

Artist Nick Ryan poseswith his "Machine 9," a work of scientific art that transforms the movement of 27,000 tracked space junk objects into sound as they are detected overhead, at the Science Museum in February 2017 in London, England. AP Photo/Alastair Grant
Artist Nick Ryan poseswith his "Machine 9," a work of scientific art that transforms the movement of 27,000 tracked space junk objects into sound as they are detected overhead, at the Science Museum in February 2017 in London, England. AP Photo/Alastair Grant

Scientists are warning people about orbital junk. These leftover parts and old satellites have been left in orbit around planet Earth. The orbital junk could be a danger to future missions in space.

The scientists spoke at a conference in Germany. In less than 25 years, the scientists said, the number of orbiting fragments large enough to destroy a spacecraft has more than doubled.

The estimated tally of tiny objects is now around 150 million. The smaller parts can harm or damage spacecraft if they run into each other, and they are hard to track.

"We are very much concerned," said Rolf Densing, director of operations at the European Space Agency, or ESA. He begged for a worldwide effort to tackle the mess.

"This problem can only be solved globally," he said.

Risks Rise Along With Litter

The junk is dangerous because it moves incredibly fast, around 17,500 miles per hour. Even a very small object can hit with enough force to damage the surface of a satellite or manned spacecraft.

In 1993, ground-based radar showed about 8,000 manmade objects in orbit that were larger than 4.5 inches across. These objects are big enough to cause catastrophic damage, said Holger Krag. He is in charge of ESA's space junk office. He explained that there are about 5,000 objects in space larger than 3.25 feet across, as well 20,000 4-inch-long objects and 750,000 objects half an inch across. 

"For objects larger than 1 millimeter, 150 million is our model estimate for that."

According to researchers' mathematical calculations, the risk of a crash is not very likely. However, the chances rise as the litter increases and more and more satellites are sent into space.

Krag warned that the amount of junk in space is not merely rising at a steady pace. It is growing at an increasingly rapid rate. 

Experts Seek Ways To Reduce Junk

The conference is being held in Darmstadt, Germany, and it broadcast its opening speeches on the internet. It is the biggest-ever gathering dedicated to space junk.

Experts will spend four days discussing the problem. They will consider measures to reduce space litter, such as by "de-orbiting" satellites at the end of their working lives.

Krag pointed to two events that have made the problem much worse by creating junk fields. These fields may create more junk as pieces smash into each other.

The first was in January 2007, when China tested an anti-satellite weapon on an old Fengyun weather satellite. At the time, the move sparked an outcry by orbital junk experts.

The other was in February 2009. An Iridium telecoms satellite used for cellphone and internet communication and a Russian military satellite, accidentally collided.

Space Station Crew Needs Notice

Given enough warning, satellites can move a little bit to avoid a crash. However, this uses up fuel and potentially shortens the satellite's working life.

ESA receives a "high risk of crash" alert message every week on average for 10 of its science satellites in low-Earth orbit, Krag said. Each has to resort to "one or two" avoidance actions per year.

French astronaut Thomas Pesquet delivered a message to the conference from the International Space Station, or ISS. He said the manned outpost in space was shielded for objects less than half an inch across. 

The ISS often has to move to avoid junk but needs 24 hours' warning to be able to do this, he said.

If there is less time, Pesquet explained, the crew has to close the hatches and enter the safe zone of the ISS. The safe zone is a smaller Russian spacecraft that can leave the ISS in the case of a crash. "This has happened four times in the history of the ISS program," he said.

Join for a free account to read the full article.
Related Articles
Related Text Sets



You must be a registered user

to submit quizzes.

Anchor 5: Text Structure

How does the introduction [paragraphs 1-5] relate to the section "Risks Rise Along With Litter"?


Both sections explain why orbital junk is a serious problem.


Both sections give reasons for why orbital junk has increased.


The introduction describes a problem with orbital junk, and the second section describes a solution.


The introduction defines what orbital junk is, and the second section discusses accidents caused by orbital junk.

Anchor 5: Text Structure

Why does the author include the section "Experts Seek Ways To Reduce Junk"?


to highlight several possible solutions and to give a chronological overview of key events


to describe the purpose of a conference and to outline what has made the problem worse


to highlight the concern of experts and to provide a definition of junk fields


to describe the conference roles of three countries and to explain the perspective of an ESA leader

Anchor 8: Arguments & Claims

How does Pesquet help justify the idea that orbital junk can disrupt missions?


by explaining that the ISS is equipped with shields to protect the spacecraft from small junk


by explaining that the crew may have to leave the ISS if there is not enough time to avoid space junk


by emphasizing that the ISS can easily prevent crashes with orbital junk if enough notice is given


by emphasizing that "high risk of crash" alerts only occur a couple of times each year

Anchor 8: Arguments & Claims

Which claim from the article is NOT supported by evidence in the article?


Experts are considering measures to reduce the amount of junk orbiting around Earth.


Even small orbital junk is dangerous because it moves at incredibly fast speeds.


Two events have made the problem of space junk much worse by creating junk fields.


Crew members have had to enter a safe zone of the ISS four times in the history of the ISS program.


{{ answers_for_review[0].student.user.first_name }} {{ answers_for_review[0].student.user.last_name }}
Write Preview

Write is a feature that allows students to answer open-ended questions. Teachers are able to customize which questions they want to ask their students.

Sample Prompt

Write a short paragraph that explains the central idea of the article. Use at least two details from the article to support your response.

Escriba un párrafo corto que explique la idea central del artículo. Use al menos dos detalles del artículo para apoyar su respuesta.

Select a class for your response
{{}} / {{teacher.user.last_name}},
Edit Prompt
Your Prompt

Note: Some of your students have already responded to the default prompt. You are editing a prompt that students have already written against. Editing the prompt now may affect the meaning of existing student work.

Recommended Annotation Visible only to you

Unable to save at this time.