Laser-firing spacecraft lauded by Leicester Director

Posted by ap507 at Jan 20, 2017 11:30 AM |
Professor of Earth Observation Science says new instrument will shed light on ‘holy grail’ of earth observation
Laser-firing spacecraft lauded by Leicester Director

ADM Aeolus (courtesy of ESA)

Professor John Remedios, Head and Professor of Earth Observation Science and head of the National Centre for Earth Observation (NCEO) at our University has been involved in an event for a new European Space Agency instrument.

He attended the Aeolus press event hosted by Airbus to mark the completion of the Aeolus wind instrument for the European Space Agency and was interviewed for ITV’s Alok Jha, who reported on News at Ten (Report starts 30 minutes into transmission).

BBC reporter Jonathan Amos described the Aeolus spacecraft in his web article: “The Aeolus spacecraft will fire a laser into the atmosphere to make the first three dimensional maps of wind behaviour across the entire planet. The data will be incorporated into the models that project weather patterns a few days ahead."

“With its ultraviolet laser, it will aim to build a truly global view of how wind blows on Earth from the surface of the planet all the way up through the troposphere and into the stratosphere (from 0km to 30km).  It will achieve this by measuring how the pulses of light from its laser are scattered back off air molecules and water droplets, even particles of dust.  The return signal will betray not only the altitude of wind streams but also gather some information about their speed and direction”. 

John Remedios explained: “The molecules in the air and the clouds move with the wind and that motion causes a shift in the frequency of the return signal.  The laser sends out a signal at on frequency and you get it back at a slightly different frequency. It’s called the Doppler effect and you’ll be familiar with it from the usual story of how an ambulance siren changes as it passes you in the street."

Professor Remedios said the European Space Agency Earth Explorer Programme exists to fund research science, satellite missions to study our planet. Such missions are a priority for the UK hence the government recently invested to make the UK the leading nation in ESA EOEP-related programmes. ADM-Aeolus is the latest mission and excitingly is a British-built satellite. The satellite has just been completed at Airbus in Stevenage.

He added: “I was invited to attend because of my position as Director of NCEO to represent the UK science community. By trade, I am an atmosphere scientist so a mission to improve our knowledge of winds and circulation is of great interest.

“There are two particular things I think that are clever about Aeolus. The first is the technology.  It’s amazing that we can put this laser in space , zap the atmosphere with it and receive signals scattered back from molecules and clouds over a return journey of close to 1000 km. Secondly, the ability to measure wind as a function of height, layer on layer, has been something of a holy grail. ADM Aeolus will provide a new dimension which will improve weather forecasts and test our knowledge of the changing circulation of the atmosphere.

“These missions always produce other interesting science. At Leicester we have used NASA Calipso laser data (532 nm) to study aerosols and it will be fascinating to see how Aeolus (355 nm)compares to Calipso. Other teams in NCEO are preparing algorithms for the Earthcare satellite which will use the same laser system as Aeolus but with modifications to dedicate it for aerosols. These groups will be able to analyse Aeolus data with their prototype algorithm.

“The availability of Aeolus data next year will stimulate the community in the UK to examine global wind data and compare to models. It promises to be an exciting time.”