“Star Wars” Laser Methods Tracks Greenhouse Gases

[/caption]

It may have looked like a futuristic scene from Star Wars, but ESA’s latest technique for aiding space exploration might shed some “green light” on greenhouse gases. A recent experiment involving the Spanish Canary Islands was conducted by shooting laser beams from a peak on La Palma to Tenerife. The two-week endeavor not only increased the viability of using laser pulses to track satellites, but increased our understanding of Earth’s atmosphere.

ESA runs an optical ground station in Tenerife for communications links with satellites. The facility is part of a larger astronomical installation Observatorio del Teide run by Instituto de Astrofisica de Canarias. Credit: ESA
Known as infrared differential absorption spectroscopy, the laser method is an accurate avenue to measure trace gases such as carbon dioxide and methane. It is accomplished by linking two Earth-orbiting satellites – one a transmitter and the other a receiver – and examining the atmosphere as the beam passes between the two. As satellites orbit, they both rise and set behind Earth and radio occultation occurs. It’s a time-honored way of employing microwave signals to measure Earth’s atmosphere, but new wave thinking employs shortwave infrared laser pulses. When the correct wavelength is achieved, the atmospheric molecules impact the beam and the resultant data can then be used to establish amounts of trace gases and possibly wind. By different angular repetitions, a vertical picture can be painted which stretches between the lower stratosphere to the upper troposphere.

While it all sounded good on paper – the proof of a working model is when it is tested. Enter ESA’s optical ground station on Tenerife – a facility built on a peak 2390 meters above sea level and part of a larger astronomical installation called the Observatorio del Teide run by the Instituto de Astrofisica de Canarias (IAC).With equipment placed on two islands, the Tenerife location offered the perfect setting to install receiver hardware grafted to the main telescope. The transmitter was then assigned to a nearly identical peak on La Palma. With nothing but 144 kilometers of ocean between them, the scenario was ideal for experimentation.

Over the course of fourteen days, the team of researchers from the Wegener Center of the University of Graz in Austria and the Universities of York and Manchester in the UK were poised to collect this unique data.

The Observatorio del Roque de los Muchachos on the island of La Palma housed the equipment to transmit the infrared signal and green guidance laser across the Atlantic Ocean to the receiving station in Tenerife. The experiment was carried out to test a new satellite mission concept for measuring concentrations of atmospheric carbon dioxide and methane. Credit: ESA
While the infrared beam wasn’t visible to the unaided eye, the green guidance laser lit up the night during its runs to record atmospheric turbulence. Gottfried Kirchengast from the Wegener Center said, “The campaign has been a crucial next step towards realising infrared-laser occultation observations from space. We are excited that this pioneering inter-island demonstration for measuring carbon dioxide and methane was successful.”

Armin Loscher from ESA’s Future Mission Division added, “It was a challenging experiment to coordinate, but a real pleasure to work with the motivated teams of renowned scientists and young academics.” The experiment was completed within ESA’s Earth Observation Support to Science Element.

Nice shootin’!

Original Story Source: ESA News Release.

Tammy Plotner

Tammy was a professional astronomy author, President Emeritus of Warren Rupp Observatory and retired Astronomical League Executive Secretary. She’s received a vast number of astronomy achievement and observing awards, including the Great Lakes Astronomy Achievement Award, RG Wright Service Award and the first woman astronomer to achieve Comet Hunter's Gold Status. (Tammy passed away in early 2015... she will be missed)

View Comments

  • Differential Absorption; IR, Vis, & UV has been used since the late '60's to measure atmospheric constituents. Most commonly pollutants like SO2 and O3 were measured by differential absorption and particulate loading by Mie scattering (straight LIDAR).

Recent Posts

ISS Crew Return Safely to Earth

After 196 days in space, some record spacewalks, several experiments, and patching an air leak,…

12 hours ago

What Martian Settlers Need to Know About Soil Can Teach us How to Grow Better on Earth

The Soil Health in Space experiment is now being conducted on the ISS, which could…

13 hours ago

This is What Perseverance’s Landing Site Looked Like Billions of Years Ago. See Why it’s Such a Compelling Target?

Today is a milestone in NASA's Perseverance mission to Mars. At 1:40 pm Pacific time…

2 days ago

Scientists in Japan Have Found a Detailed Record of the Earth’s Last Magnetic Reversal, 773,000 Years Ago

Every 200,000 to 300,000 years Earth's magnetic poles reverse. What was once the north pole…

2 days ago

Boo! A Halloween Blue Moon

The final ‘Blue Moon’ of the decade rounds out October 2020.

2 days ago

OSIRIS-REx Collected So Much Material, the Sample Capsule Overflowed. Time to Bring it All Home.

Is there such as thing as too much asteroid? Scientists and engineers for NASA’s OSIRIS-REx…

2 days ago