Space collisions could rise due to more CO2 - study

LONDON Sun Nov 11, 2012 11:35pm IST

A 3D animation of China's Tiangong-1 space module is shown in this still image taken from video released September 28, 2011. REUTERS/Jiuquan Satellite Launch Centre/Handout/Files

A 3D animation of China's Tiangong-1 space module is shown in this still image taken from video released September 28, 2011.

Credit: Reuters/Jiuquan Satellite Launch Centre/Handout/Files

Related Topics

LONDON (Reuters) - More satellites and orbiting debris could collide in the upper atmosphere because a buildup of carbon dioxide (CO2) has reduced the "drag effect" which can eventually send some space junk back down to Earth, a study shows.

Over the past eight years CO2 concentrations in the upper atmosphere have risen from burning fossil fuels that have warmed the Earth's surface and caused temperatures to increase, the study in the journal Nature Geoscience said.

This can result in a cooler, less dense atmosphere above a 90-km (55-mile) altitude, the study said, adding that this "will reduce atmospheric drag on satellites and may have adverse consequences for the orbital debris environment that is already unstable".

Less drag, or friction, in the upper atmosphere means space debris such as redundant satellites and defunct rocket bodies will stay at a certain altitude for longer, increasing the risk of collisions.

Global temperatures are now about 0.8 degree C (1.4 F) above pre-industrial times. Two degrees is viewed as a threshold to dangerous change including more powerful storms like Sandy that struck the United States this month, more heatwaves, droughts and rising sea levels.

The scientists, from the Naval Research Laboratory in Washington, Old Dominion University in Virginia, University of Waterloo in Ontario and the University of York in Britain, used satellite data to study changes in CO2 concentrations at a 101-km altitude between 2004 and 2012 and found that CO2 rose significantly over that time.

So far, CO2 trends have been measured only up to a 35-km altitude because balloons and aircraft do not reach high altitudes, and ground measurements and rockets only provide limited coverage.

Debris is always a danger to spacecraft and collisions can prove costly for spacecraft manufacturers.

There are 21,000 bits of debris larger than 10 cm (4 inches) in orbit, but collisions occur infrequently - about once a year on average, according to NASA, the U.S. space agency.

However, a U.S. National Research Council report in 2011 warned NASA that the amount of space debris orbiting the Earth was at critical level and the United States has been trying to develop technologies to remove debris and reduce hazards.

(Editing by Michael Roddy)

FILED UNDER:
Comments (0)
This discussion is now closed. We welcome comments on our articles for a limited period after their publication.

  • Most Popular
  • Most Shared

REUTERS SHOWCASE

School Shooting

School Shooting

Two killed, four wounded in Washington state school shooting.  Full Article 

Sundar Pichai Elevated

Sundar Pichai Elevated

Google's Pichai to oversee major products and services.  Full Article 

Need For Reforms

Need For Reforms

Euro zone risks "relapse into recession" without structural reforms - Draghi.  Full Article 

Diwali Sales

Diwali Sales

Gold sales jump about 20 pct for Diwali - trade body  Full Article 

World Bank Rival

World Bank Rival

Three major nations absent as China launches W.Bank rival in Asia  Full Article 

Wal-Mart India

Wal-Mart India

Murali Lanka appointed as Wal-Mart India operations chief  Full Article 

Health Of Lenders

Health Of Lenders

25 European banks set to fail health checks - sources.  Full Article 

Special Report

Special Report

Why Madrid's poor fear Goldman Sachs and Blackstone  Full Article 

India Insight

India Insight

Kalki Koechlin on her role as a disabled girl in “Margarita, With a Straw”  Full Article 

Reuters India Mobile

Reuters India Mobile

Get the latest news on the go. Visit Reuters India on your mobile device.  Full Coverage