In Situ,Remote,and Laboratory Investigations of Mesospheric Aerosols/Dust and Their Role in Atmospheric Chemical and Physical Processes.

The main goal of the project is to improve our understanding of the physics and chemistry of the mesosphere in order to include this part of the Earth atmosphere in climate models. Better knowledge on the chemical properties of nanoparticles in the middle atmosphere is an important aspect in this context. A lot of the chemistry in this height region occur on the surfaces of ice and dust particles, which can function as nucleation kernels for cloud particles, even in the stratosphere. We expect that rocket observations yield a better understanding of the connection between the mesosphere and the neighboring layers above and below, and how the processes in the upper mesosphere may influence lower parts of the atmosphere. Two rocket campaigns were made from Andøya space center to measure the mesospheric dust and plasma during summer conditions. In summer, ice particles form around smaller refractory dust and the ice particles are observed in noctilucent clouds and are involved in a dusty plasma process that leads to formation of strong radar echoes, called polar mesospheric summer echoes (PMSE). The data were analyzed and led to a number of important new findings published in scientific journals. The scientific results of the project include the first detection of rare low summer echoes simultaneously with radar and the rocket in-situ observations. A PhD dissertation carried out within the project among other results developed a novel approach to measure the size distribution of the nanoparticles. A new instrument to measure smaller dust was developed and tested in a student rocket experiment during winter conditions when the dust particles are typically smaller. This resulted in two master thesis and also scientific publications. The design development work for a future sample collector continued and the design considerations will be published for usage in future projects. We also participate in discussions on planning future rocket observations of the mesosphere in Norway. The work on the project included collaborations with researchers from five different countries and we plan to continue these collaborations in future work.

The Maxidusty projects strengthened international collaborations on the studies of the upper atmosphere from Andøya. results support a new initiative to establish an international research programme to study the mesosphere above the Arctic using rocket measurements from Andøya Space Center. Students at UiT were directly involved in the project, which enhanced their motivation to pursue a career in space research and technology. The experience from the project and project work were central for the participation of UiT students from Tromsø and Narvik in the international G-Chaser student rocket campaign and reports in the media reached the next generation of potential students. Results of the project also enter a number of other projects including the preparation of observations with the new EISCAT_3D radar. For future research the project provides new results that are important for research on the Earth atmosphere, interplanetary space and for cosmic environments, in general.

The aim of the MAXIDUSTY-II project is to enhance our understanding of key physical and chemical processes in the Earths mesosphere and of its coupling to other atmospheric regions. The investigations will involve the launch of rocket payloads MAXIDUSTY-I and II which will include several recently developed dust and plasma probes and a new dust probe, MESS. Using a new sampling technique, MESS will collect and return meteoric smoke particles for the first time. The launch will be supported by the EISCAT radars and Heating Facility and the UiT MORRO 56 MHz radar , by all relevant ground-based instrumentation at Andøya Rocket Range, and by satellite observations. The major goals of the investigations are to reveal the chemical content of the mesospheric cloud (NLC/PMC) particles by in situ mass spectroscopy, weigh collision fragments from impacting ice particles, find the secondary charging effects, mass analyze the incoming primary dust particles, and analyze smoke particles brought back by the MESS probe. This, combined with the other rocket, satellite, and ground-based observations, together with theoretical modeling and laboratory experimental results, will lead to an improved understanding of smoke and PMC particle formation and evolution, and of the chemical and physical processes occurring in the mesosphere. The new knowledge that will emerge from the MAXIDUSTY-I and II projects is expected to be important in validating and improving Whole Atmosphere Models, and satellite observation techniques, as well as laboratory experiments related to chemical processes in the upper atmosphere. In the MXD project we will also install and equip a large plasma vacuum tank for instrument testing to ensure the optimal performance of the payload probes. The payload will carry up to four small daughter payloads to be ejected in the mesosphere to conduct 3D measurements of vital parameters such as the plasma density and possibly the dust charge density.