UNOOSA and ESA space debris infographics and podcasts


10 February 2021

What is this series about?

Space debris is an issue of global concern that threatens our continued use of near-Earth space for the benefit of humankind. To raise awareness about this growing problem, ESA and the United Nations Office for Outer Space Affairs (UNOOSA) have created a series of nine infographics and podcasts that tell the story of space debris, explain the risks and illustrate the solutions available to ensure future space exploration remains sustainable. Scroll down to see the infographics and listen to the podcasts. 

A limited natural resource

Space may seem vast, but the orbits around Earth in which satellites reside are a limited natural resource. Accidental collisions, explosions and even the intentional destruction of satellites have created millions of debris fragments, which, orbiting at high speed, can damage or destroy any functioning spacecraft that crosses their path.

As satellite technology becomes ever more relied upon, it gets increasingly important to protect these unique orbital regions that are essential for humanity to, for example, gather data for weather forecasting and to better understand extreme weather and our changing climate, as well as for internet access, communication and location services. 

A concern to all nations

Unfortunately, the amount of space debris in orbit is increasing at an exponential rate. As a growing number of countries and actors begin space activities - a hugely positive development in general - and as satellite operations become more complex and the number of objects being launched, including in large constellations, rapidly increases, so too do the challenges posed to our space environment.

In 2019, ESA's Space Safety programme was adopted as a key pillar in the Agency's activities. The programme, an expansion of the former Space Situational Awareness programme, includes ESA's Space Debris and Clean Space Offices, which are working to better understand the debris environment, prevent the creation of more debris, reduce the amount in orbit and lessen the impact of space activities on Earth.

In 2018, the United Nations General Assembly expressed its worry about the fragility of the space environment and the impact of space debris, which is an issue of concern to all nations. In 2019, the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS), of which UNOOSA is Secretariat, adopted the Guidelines for the Long-Term Sustainability of Outer Space Activities (LTS Guidelines), which provide guidance to help ensure the safe and sustainable use of space. The LTS Guidelines were subsequently welcomed with appreciation by the United Nations General Assembly, and a new working group will continue multilateral discussions on the topic.

Raising awareness

This new series of infographics jointly produced by UNOOSA and ESA include attractive, easy to understand illustrations, facts and figures so that everyone, with or without any previous knowledge of spaceflight, can understand space debris and the challenge it poses. They cover topics such as how debris is created, how to avoid collisions, the risk to humans in space from debris and on Earth from re-entries, as well as technologies for safe debris mitigation and removal.

Each of the nine infographics is accompanied by a podcast with audio commentary from UNOOSA and ESA experts, who help navigate and understand the material.

Infographics and podcasts will be released here, once a week, over a period of nine weeks, starting on 10 February 2021, as well as via @UNOOSA and @ESA social media accounts.

"A new era of space has begun, in which large constellations of thousands of satellites are being launched to the skies," said ESA Director Jan Wörner. "What this 'New Space' makes possible - global internet access, telecommunications - it also threatens, as a rapid increase in space traffic may dramatically increase the chance of collisions. Innovative technologies, responsible behaviour and importantly international cooperation are fundamental to ensuring our future in space is sustainable."

UNOOSA Director Simonetta Di Pippo said: " Space debris poses a clear risk for the long-term sustainability of outer space activities. Space economy calls for a safe, secure and sustainable space environment. UNOOSA welcomes working with  ESA to disseminate clear, accessible public information on space debris that will increase awareness of the challenges they pose and contribute to strengthening international cooperation on mitigation measures."

Infographic 1: satellites versus debris

Space debris is a topic of global concern. While space has brought huge benefits to individuals and societies across the globe, the rapid increase of launched objects and increased traffic in our space highways means we are creating ever-more debris and threatening the very technologies we have come to rely on. Acknowledging the significance of this problem, UNOOSA and ESA have come together to raise awareness with a series of nine infographics that tell the space debris story so far and illustrate some of the solutions available for us to achieve a sustainable use of space. 

Satellites in orbit share near-Earth space with millions of fast-moving and dangerous debris objects. From tiny fragments millimetres in size to entire satellites no longer working, no longer controlled, roaming the space highways, each debris piece travels many kilometres per second. Any impact with one of these objects threatens to at least impair the functioning of a working spacecraft, or at worst destroy it altogether, creating ever more debris. In this infographic from ESA and the UN, find out about the scale of the debris problem: how much of it is up there, what scales are we talking about, and what are our satellites are up against? Find out more in Episode one of the corresponding ESA & UN podcast below, "Satellites vs. debris".

Listen to the podcast here:  https://soundcloud.com/esa/satellites-vs-debris  

Infographic 2: falling to Earth takes a long time
 

Our planet's atmosphere reduces the energy of satellites in orbit (on Earth, this would be like reducing their speed, but in space, it's complex!). This gradually then brings them back down to Earth. This process can be relatively fast for satellites flying at lower altitudes, taking less than 25 years, but for satellites launched into orbits tens of thousands of km away, it can be thousands of years before they return, if the atmosphere is even able to impact them at all. Had the dinosaurs launched a satellite into the furthest geostationary orbit, it would still be up there today. This means that as we launch satellites to space we must consider how they will be removed at the end of their lives, or else the skies will be filled with old, defunct spacecraft at risk of collision, explosion, and the near-certain creation of vast amounts of space debris. In this infographic from ESA and the UN, find out how long it would take satellites at different altitudes to naturally fall back to Earth, and what must be done responsibly dispose of them at the end of their lives. Find out more in Episode two of the corresponding ESA & UN podcast below, "Falling to Earth takes a long time".
 
Listen to the podcast here:   https://soundcloud.com/esa/falling-to-earth-takes-a-long-time 
 
Infographic 3: the cost of avoiding collisions
 
 
Space might seem an empty, vast expanse, but satellites in Earth's orbit face the constant risk of collision - with other satellites, dead or alive, or with fragments of debris. It is now routine for operators of spacecraft in busy highways to divert their mission out of harms way. In fact at ESA, each mission flown performs on average two 'collision avoidance manoeuvres' per year. These manoeuvres are costly. Hours are spent on the ground monitoring the skies, calculating the risk and planning manoeuvres, not to mention the extra fuel spent and missed science and data collected while instruments are turned off. Find out more in the podcast below.
 
Listen to the podcast here:  https://soundcloud.com/esa/avoiding-collision 
 
Infographic 4: we are launching more than ever
 
 
Since the beginning of the space age, with the launch of Sputnik in 1957, we have launched thousands of rockets carrying more than ten thousand satellites into space. The last few years have seen a dramatic increase in these numbers, and over the last few decades there has been a change in the type of mission flown, with private companies (yellow) launching smaller satellites than those launched by non-commercial agencies (blue). This graph, created in a joint project between ESA and the UN, also shows the number of unregistered objects (red) has increased in recent years. It should be noted that these are objects not yet registered with the UN, and are expected to rise. Find out more about why this matters in the joint ESA-UN podcast that narrates this space debris infographic series.
 
Listen to the podcast here:  https://soundcloud.com/esa/launching-more
 
Infographic 5: the role of reentries
 
 
What goes up, nearly always comes back down. When it comes to the objects we send to space, atmospheric reentries are actually a fundamental tool in minimising the creation of space debris, and ensuring a sustainable future in space. Objects in low-Earth orbit, affected by the 'drag' forces caused by Earth's atmosphere, gradually lower in altitude and then make a rapid and firey descent towards Earth. Small objects disintegrate as they reenter due to the immense friction and heat created, but parts of larger bodies can reach the ground, so should be controlled to land over uninhabited regions. Find out more about why this matters in the joint ESA-UNOOSA podcast that narrates this space debris infographic series below.
 
Listen to the podcast:  https://soundcloud.com/esa/the-role-of-reentries 
 
Infographic 6: the history of space debris
 
 

The millions of fragments of debris in orbit today are the direct result of 'fragmentation events' in the past. Of the 550 events known to date, those caused by propulsion have created the greatest amount of space debris. Energy left undisposed of on-board a satellite or rocket body can lead to explosions. For this reason, the international space debris mitigation guidelines require that satellites are 'passivated' at the end of their mission - for example by emptying fuel tanks and disconnecting batteries. Because of these guidelines, and passivation technologies being developed by ESA and others, we expect a graph for the future to have far fewer propellant-fueled explosions. However, as traffic in space rapidly increases, the number of collisions is expected to rise. Find out how we know about the causes of debris-creating events, and how this can help us prevent them in the joint UNOOSA-ESA podcast below that narrates this infographic. 

Listen to the podcast here:  https://soundcloud.com/esa/where-todays-debris-came-from  

Infographic 7: the impact of space debris

Debris in orbit varies from millions of millimetre-sized particles to thousands of much larger objects like defunct satellites and rocket parts. As such the damage debris can cause varies from a gradual degradation of satellite parts over time to its immediate and total destruction. The NASA/ESA Hubble Space Telescope has experienced decades of constant, minor bombardment from small debris objects, but collisions between entire satellites have also taken place, creating thousands of debris fragments. Debris objects travel at about 10 km/s, meaning a collision with just 1cm fragment can create the same amount of energy as a small car crashing at 40 km/h!

Find out more about the damage done by debris in the joint UNOOSA-ESA podcast that narrates this infographic below.

Listen to the podcast: https://soundcloud.com/esa/the-impact-of-space-debris  

Infographic 8: space debris and human spaceflight

Humans in space have a lot to contend with, and for those in low-Earth orbit,  space debris is a real concern.The  International Space Station orbits Earth at an altitude of just over 400 km. In the two decades since its launch, 28 ' collision avoidance manoeuvres' have been performed in order to dodge space debris, with three taking place in 2020 alone. If a potential collision appears imminent, and there is no time to move the Station, they can take emergency shelter. To date, five 'shelter-in-place' manoeuvres have taken place, using the docked Soyuz spacecraft.

Find out more about the risk space debris poses to astronauts, including the "clanking" sounds they hear while in orbit, in the joint  ESA-UNOOSA podcast that narrates this infographic. 

Infographic 9: sustainable space

 

Space may seem vast, but the orbits around Earth in which satellites reside are a limited natural resource. However, since the beginning of the space age, millions of debris fragments have been created which now threaten any spacecraft that crosses their path. Satellite technology is now relied on around the world, and will become even more so. As such, it is becoming increasingly important to protect the unique orbital regions from where vital data is gathered for weather forecasting, climate research, communications and location services. There are many trends that threaten the long-term sustainability of space - increasing space traffic, more complex space operations and large constellations to name a few - but there are also approaches to secure our sustainable future. Find out more about how we can tackle space debris and secure near-Earth space for future generations in the joint UNOOSA-ESA podcast that narrates this infographic.

Listen to the podcast:    https://soundcloud.com/esa/long-term-sustainability  

Concluding the series is a conversation between UNOOSA Director Simonetta Di Pippo and ESA Director General Joseph Aschbacher, on the growing issue of space debris and how the international community can find collective solutions. Listen to it here!

Copyright ©2021 UNOOSA, All Rights Reserved