Space collisions could rise due to more CO2

Updated 16 November 2012

Space collisions could rise due to more CO2

LONDON: 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 US space agency.
However, a US 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.


Pentagon awards United Launch Alliance, SpaceX launch contracts

Updated 09 August 2020

Pentagon awards United Launch Alliance, SpaceX launch contracts

  • The two companies lay claim to billions of dollars in lucrative military contracts for a span of five years

WASHINGTON: The US Air Force said it awarded United Launch Alliance (ULA) and Elon Musk’s SpaceX $653 million in combined military launch contracts under the Pentagon’s next-generation, multibillion-dollar launch capability program.

The contracts are for launch service orders beginning in 2022 and allocate $337 million to ULA, a joint venture between Boeing and Lockheed Martin Corp., and $316 million to SpaceX for the first missions of roughly 34 total that the two rocket firms will support through 2027.

ULA will receive a contract for approximately 60 percent of those launch service orders using its next-generation Vulcan rocket, while Musk’s SpaceX, using its Falcon 9 and Falcon Heavy rockets, will receive approximately 40 percent, the Air Force’s acquisition chief Will Roper told reporters on Friday.

The awards are part of the Pentagon’s 2014 mandate from Congress to curb its dependency on rockets using Russia’s RD-180 engine and transition to US-made rockets for launching Washington’s most sensitive national security payloads to space.

The program, called National Security Space Launch Phase 2, is aimed at “building a competitive industry base that we hope doesn’t just help military and national security missions, but that helps our nation continue to compete and dominate in space,” Roper added.

“Today’s awards mark a new epoch of space launch thatwill finally transition the Department off Russian RD-180 engines,” Roper said in a statement.

The two companies lay claim to billions of dollars in lucrative military contracts for a span of five years that competitors Blue Origin, the space company of Amazon.com Inc. owner Jeff Bezos, and Northrop Grumman also competed for.

Blue Origin Chief Executive Bob Smith said in a statement he was “disappointed” in the Pentagon’s decision, adding that the company will continue to develop its heavy-lift New Glenn rocket “to fulfill our current commercial contracts, pursue a large and growing commercial market, and enter into new civil space launch contracts.”