ASIM was launched in April 2018 and is mounted on The International Space Station (ISS) about 400 km above the Earth. (Photo: ESA)

New knowledge about giant lightning bolts in space

Tuesday 09 Apr 19


Torsten Neubert
Chief Consultant
DTU Space
+45 45 25 97 31

ASIM: A Danish-led project

The ASIM (Atmosphere-Space Interactions Monitor) project is anchored at the European Space Agency, ESA.


DTU Space is in charge of the scientific management of the project and has built parts of the instruments. The Danish company Terma heads the technical part of the project and the industrial consortium which has built ASIM. The Danish Meteorological Institute (DMI) provides global meteorological data and helps interpret them scientifically.


The Ministry of Higher Education and Science has supported the ASIM project, through a special contribution from the globalization pool in the period 2009-2012 for climate initiatives through the European Space Agency, ESA, and by other contributions via membership of ESA. 


In addition, University of Bergen in Norway, University of Valencia in Spain, as well as partners from Poland and Italy, participate. In addition ASIM over time will involve about 80 research groups from 30 countries.

Measurements from the large ASIM space project shows a firework of blue lightning and X-ray radiation above thunderclouds.

After one year in space, the ASIM (Atmosphere-Space Interactions Monitor) observatory on the International Space Station (ISS) has given researchers from Denmark’s Technical University (DTU) a new and better understanding of how lightning is created, and how thunderstorms can affect the stratosphere and the climate.

The first measurements show what creates the so-called ‘terrestrial gamma-flashes’ in the atmosphere. The flashes occur in connection with lightning and thunder storms and are short bursts of high-energy X- and gamma- rays. At the same time, the researchers have received measurements showing a wealth of blue lightning above the thunderclouds.

The discoveries have just been published at a European Geosciences Union (EGU) conference in Vienna. During the year, DTU researchers will describe the results of the research in more detail in a number of scientific articles. Here it will be evident how lightning creates these ‘terrestrial gamma-flashes’, that were discovered back in 1993.

“We can really see new things and have gained so much knowledge on the internal anatomy of the lightning. Besides the ‘terrestrial gamma-flashes’ our recordings show lots of blue lightning that spread like fireworks above thunderclouds. It looks crazy,” says Torsten Neubert, lead scientist for the ASIM project and Senior Executive Officer at DTU Space. He is pleased that ASIM lives up to expectations.

The observatory was sent to the ISS on 2 April 2018 to monitor the violent thunderstorms and lightning that appear above the clouds and uncover the invisible processes that drive them.

One of the invisible processes are gamma-ray flashes from thunder and lightning. A phenomenon known as terrestrial gamma-ray flashes (TGFs). ASIM is also investigating energy discharges driven by thunderstorms in the area from the top of the clouds and up to 100 km above the ground.

Highlight for Danish astronaut Andreas Mogensen

Already back in 2015, the Danish ESA astronaut Andreas Mogensen succeeded in filming a spectacular thunderstorm over the Indian Ocean while on board the ISS.

"ASIM is an excellent example of the exciting and important research we carry out aboard the International Space Station"
Andreas Mogensen, Danish ESA astronaut

Here he caught a so-called Blue Jet that can reach altitudes of 50 km.

But that was not all. For the first time, the Blue Jet was seen pulsating. This means that the lightening fires upwards several times in quick succession. He also caught a lot of blue flashes near the top of the cloud.

These recordings were important for DTU; partly because they are the best shots ever taken, partly because they are taken from an angle that makes it easier for researchers to understand what is happening.

“ASIM is an excellent example of the exciting and important research we carry out aboard the International Space Station,” says Andreas Mogensen.

“Research that will contribute with new knowledge about our world. Filming the blue lightning was undoubtedly one of the highlights of my mission in 2015.”

New update will enhance accuracy

For the past six months, the Danish company Terma, who heads the technical part of the project, has completed an upgrade of the computer programs that control ASIM’s two main instruments.

One of the instruments is the MXGS (Modular X- and Gamma-ray Sensor). The second instrument -  the Modular Multi-spectral Imaging Array (MMIA) - consists of two cameras and three photometers that detect flashes of light at different wavelengths.

“The updates will give the researchers better measurements, because the instruments have become more sensitive in relation to capturing gamma radiation and gigantic lightning above the clouds. It will also improve the time accuracy between the two instruments to better than ten millionths of a second, which again will improve the analysis of the signals from the many sensors,” says Senior Project Manager Ole Hartnack from Terma.

The excellent data means that DTU researchers consider applying for an extension of the mission beyond the planned duration of two years. It will also offer an opportunity to study the Northern Lights and meteors.

Read more here at our ASIM page

Story written by: Christina Tækker

SEE OUR DOCUMENTARY ABOUT ASIM: The search for the magic lightnings

Click on the link beneath to watch the awesome film about the ASIM project. Here you can watch the launch that took place 2 April 2018 and meet the scientists and engineers behind the project as well as Danish ESA astronaut Andreas Mogensen:


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