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1. First Radar -- CubeSat Transionospheric HF Propagation Observations: Suomi 100 Satellite and EISCAT HF Facility

Author

Kallio, Esa, Kero, Antti, Harri, Ari-Matti, Kestilä, Antti, Aikio, Anita, Fontell, Mathias, Jarvinen, Riku, Kauristie, Kirsti, Knuuttila, Olli, Koskimaa, Petri, Loyala, Jauaries, Lukkari, Juha-Matti, Modabberian, Amin, Niittyniemi, Joonas, Rynö, Jouni, Vanhamäki, Heikki, and Varberg, Erik

Subjects
Physics - Space Physics, Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Radio waves provide a useful diagnostic tool to investigate the properties of the ionosphere because the ionosphere affects the transmission and properties of High Frequency (HF) electromagnetic waves. We have conducted a transionospheric HF-propagation research campaign with a nanosatellite on a low-Earth polar orbit and the EISCAT HF transmitter facility in Troms{\o}, Norway, in December 2020. In the active measurement, the EISCAT HF facility transmitted sinusoidal 7.953 MHz signal which was received with the HEARER radio spectrometer onboard 1 Unit (size: 10 cm x 10 cm x 10 cm) Suomi 100 space weather nanosatellite. Data analysis showed that the EISCAT HF signal was detected with the satellite's radio spectrometer when the satellite was the closest to the heater along its orbit. Part of the observed variations seen in the signal was identified to be related to the heater's antenna pattern and to the transmitted pulse shapes. Other observed variations can be related to the spatial and temporal variations of the ionosphere and its different responses to the used transmission frequencies and to the transmitted O- and X-wave modes. Some trends in the observed signal may also be associated to changes in the properties of ionospheric plasma resulting from the heater's electromagnetic wave energy. This paper is, to authors' best knowledge, the first observation of this kind of "self-absorption" measured from the transionospheric signal path from a powerful radio source on the ground to the satellite-borne receiver., Comment: 27 pages, 10 images

Published
2022
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2. Auroral imaging with combined Suomi 100 nanosatellite and ground-based observations: A case study

Author

Kallio, Esa, Harri, Ari-Matti, Knuuttila, Olli, Jarvinen, Riku, Kauristie, Kirsti, Kestilä, Antti, Kivekäs, Jarmo, Koskimaa, Petri, Lukkari, Juha-Matti, Partamies, Noora, Rynö, Jouni, and Syrjäsuo, Mikko

Subjects
Physics - Space Physics, Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Auroras can be regarded as the most fascinating manifestation of space weather and they are continuously observed by ground-based and, nowadays more and more, also by space-based measurements. Investigations of auroras and geospace comprise the main research goals of the Suomi 100 nanosatellite, the first Finnish space research satellite, which has been measuring the Earth's ionosphere since its launch on Dec. 3, 2018. In this work, we present a case study where the satellite's camera observations of an aurora over Northern Europe are combined with ground-based observations of the same event. The analyzed image is, to the authors' best knowledge, the first auroral image ever taken by a cubesat. Our data analysis shows that a satellite vantage point provides complementary, novel information of such phenomena. The 3D auroral location reconstruction of the analyzed auroral event demonstrates how information from a 2D image can be used to provide location information of auroras under study. The location modelling also suggests that the Earth's limb direction, which was the case in the analyzed image, is an ideal direction to observe faint auroras. Although imaging on a small satellite has some large disadvantages compared with ground-based imaging (the camera cannot be repaired, a fast moving spinning satellite), the data analysis and modelling demonstrate how even a small 1-Unit (size: 10 cm x 10 cm x 10 cm) CubeSat and its camera, build using cheap commercial off-the-shelf components, can open new possibilities for auroral research, especially, when its measurements are combined with ground-based observations., Comment: Accepted manuscript 34 pages, 17 figures

Published
2022
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3. Retrieval of Water Vapor Column Abundance and Aerosol Properties from ChemCam Passive Sky Spectroscopy

Author

McConnochie, Timothy H., Smith, Michael D., Wolff, Michael J., Bender, Steve, Lemmon, Mark, Wiens, Roger C., Maurice, Sylvestre, Gasnault, Olivier, Lasue, Jeremie, Meslin, Pierre-Yves, Harri, Ari-Matti, Genzer, Maria, Kemppinen, Osku, Martínez, Germán M., DeFlores, Lauren, Blaney, Diana, Johnson, Jeffrey R., and Bell III, James F.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We derive water vapor column abundances and aerosol properties from Mars Science Laboratory (MSL) ChemCam passive mode observations of scattered sky light. Each ChemCam passive sky observation acquires spectra at two different elevation angles. We fit these spectra with a discrete-ordinates multiple scattering radiative transfer model, using the correlated-k approximation for gas absorption bands. The retrieval proceeds by first fitting the continuum of the ratio of the two elevation angles to solve for aerosol properties, and then fitting the continuum-removed ratio to solve for gas abundances. The final step of the retrieval makes use of the observed CO2 absorptions and the known CO2 abundance to correct the retrieved water vapor abundance for the effects of the vertical distribution of scattering aerosols and to derive an aerosol scale height parameter. The ChemCam-retrieved water abundances show, with only a few exceptions, the same seasonal behavior and the same timing of seasonal minima and maxima as the TES, CRISM, and REMS-H data sets that we compare them to. However ChemCam-retrieved water abundances are generally lower than zonal and regional scale from-orbit water vapor data, while at the same time being significantly larger than pre-dawn REMS-H abundances. Pending further analysis of REMS-H volume mixing ratio uncertainties, the differences between ChemCam and REMS-H pre-dawn mixing ratios appear to be much too large to be explained by large scale circulations and thus they tend to support the hypothesis of substantial diurnal interactions of water vapor with the surface. Our preliminary aerosol results, meanwhile, show the expected seasonal pattern in dust particle size but also indicate a surprising inter-annual increase in water-ice cloud opacities., Comment: 64 pages with embedded figures; this is the accepted version of the manuscript; the meta-data version of the abstract has been shorted to meet arXiv rules

Published
2017
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6. Improving relative humidity measurements on Mars: New laboratory calibration measurements.

Author

Hieta, Maria, Jaakonaho, Iina, Polkko, Jouni, Lorek, Andreas, Garland, Stephen, de Vera, Jean-Pierre, Genzer, Maria, and Harri, Ari-Matti

Subjects
HYGROMETRY, MARTIAN atmosphere, MARTIAN surface, CALIBRATION, MARS (Planet), CAPACITIVE sensors, HUMIDITY, TEMPERATURE measuring instruments
Abstract

In this paper we present new calibration measurements that have been performed with the ground reference models of the relative humidity instruments of the MSL, Mars 2020 and ExoMars missions. All instruments are based on capacitive sensor head technology, and they are developed, manufactured and tested by The Finnish Meteorological Institute (FMI). Calibration of capacitive humidity sensors for the Martian environment has been a challenging task and special facilities are needed in order to create Martian conditions including all relevant environmental parameters: low pressure, low temperature, carbon dioxide environment, and especially humidity that can be accurately controlled and measured. A measurement campaign was performed at DLR PASLAB (Planetary Analog Simulation Laboratory) determining relative humidity calibration data sets for REMS-H, MEDA HS and METEO-H instruments in temperatures from -30 °C down to -70 °C in low pressure CO2. In addition to the stable point humidity calibration measurements in CO2, the instrument performance was tested with the actual Martian atmosphere composition, and during long continuous measurements. The new calibration data set has already been used in the flight calibration of the MEDA HS instrument resulting in successful calibration and excellent accuracy. The results from this campaign will further improve relative humidity measurements on Mars by providing the means to reanalyse the current calibration of the REMS-H flight model, and by allowing more accurate comparison between the two instruments currently on the Martian surface. [ABSTRACT FROM AUTHOR]

Published
2023
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7. Atmospheric movies acquired at the Mars Science Laboratory landing site: Cloud morphology, frequency and significance to the Gale Crater water cycle and Phoenix mission results

Author

Moores, John E., Lemmon, Mark T., Rafkin, Scot C.R., Francis, Raymond, Pla-Garcia, Jorge, de la Torre Juárez, Manuel, Bean, Keri, Kass, David, Haberle, Robert, Newman, Claire, Mischna, Michael, Vasavada, Ashwin, Rennó, Nilton, Bell, Jim, Calef, Fred, Cantor, Bruce, Mcconnochie, Timothy H., Harri, Ari-Matti, Genzer, Maria, Wong, Michael, Smith, Michael D., Javier Martín-Torres, F., Zorzano, María-Paz, Kemppinen, Osku, and McCullough, Emily

Published
2015
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8. The dynamic atmospheric and aeolian environment of Jezero crater, Mars

Author

Newman, Claire E., primary, Hueso, Ricardo, additional, Lemmon, Mark T., additional, Munguira, Asier, additional, Vicente-Retortillo, Álvaro, additional, Apestigue, Víctor, additional, Martínez, Germán M., additional, Toledo, Daniel, additional, Sullivan, Rob, additional, Herkenhoff, Ken E., additional, de la Torre Juárez, Manuel, additional, Richardson, Mark I., additional, Stott, Alexander E., additional, Murdoch, Naomi, additional, Sanchez-Lavega, Agustín, additional, Wolff, Michael J., additional, Arruego, Ignacio, additional, Sebastián, Eduardo, additional, Navarro, Sara, additional, Gómez-Elvira, Javier, additional, Tamppari, Leslie, additional, Smith, Michael D., additional, Lepinette, Alain, additional, Viúdez-Moreiras, Daniel, additional, Harri, Ari-Matti, additional, Genzer, Maria, additional, Hieta, Maria, additional, Lorenz, Ralph D., additional, Conrad, Pan, additional, Gómez, Felipe, additional, McConnochie, Timothy H., additional, Mimoun, David, additional, Tate, Christian, additional, Bertrand, Tanguy, additional, Bell, James F., additional, Maki, Justin N., additional, Rodriguez-Manfredi, Jose Antonio, additional, Wiens, Roger C., additional, Chide, Baptiste, additional, Maurice, Sylvestre, additional, Zorzano, Maria-Paz, additional, Mora, Luis, additional, Baker, Mariah M., additional, Banfield, Don, additional, Pla-Garcia, Jorge, additional, Beyssac, Olivier, additional, Brown, Adrian, additional, Clark, Ben, additional, Montmessin, Franck, additional, Fischer, Erik, additional, Patel, Priyaben, additional, del Río-Gaztelurrutia, Teresa, additional, Fouchet, Thierry, additional, Francis, Raymond, additional, and Guzewich, Scott D., additional

Published
2022
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9. Overview of Near-Surface Atmospheric Processes at Jezero from Meda Observations

Author

de la Torre-Juárez, Manuel, Rodríguez Manfredi, Jose, Martínez, Germán, Newman, Claire, Lemmon, Mark, Hueso, Ricardo, Munguira, Asier, Tamppari, Leslie, Sanchez-Lavega, Augustin, Apestigue, Victor, Arruego, Ignacio, Banfield, Donald, Boland, Justin, Conrad, Pamela, del Rio, Teresa, Vicente -Retortillo, Álvaro, Dominguez-Pumar, Manuel, Fischer, Erik, Genzer, Maria, Gimenez, S., Gómez Elvira, Javier, Gómez, Felipe, Guzewich, Scott, Harri, Ari-Matti, Hieta, M., Jimenez, Victor, Lepinette, Alain, Marín, M., Martin-Rubio, Carolina, Molina, Antonio, Montmessin, Franck, Mora-Sotomayor, Luis, Navarro, Sara, Peinado, Veronica, Pérez‐hoyos, Santiago, Pla‐garcía, Jorge, Polkko, Jouni, Romeral, Julio, Romero, C., Savijärvi, Hannu, Sebastian, E., Smith, M.D., Sullivan, Rob, Tate, Christian, Toledo-Carrasco, Daniel, Torres, Josefina, Urquí, Roser, Viudez-Moreiras, Daniel, Wolff, Michael, Zorzano, Maria-Paz, Zurita, Sofia, and Cardon, Catherine

Subjects
[SDU] Sciences of the Universe [physics]
Published
2022

10. Relative humidity and vapor amount at Jezero Crater

Author

Tamppari, Leslie K., Martinez, German, Rodríguez Manfredi, Jose, de la Torre-Juárez, Manuel, Hieta, M., Polkko, Jouni, Jaakonaho, I., Genzer, M., Harri, Ari-Matti, Mcconnochie, Timothy, Montmessin, Franck, Smith, Michael D., Wolff, Mike, Fisher, Erik, Conrad, Pamela, Gómez, Felipe, Zorzano, María‐paz, Viudez-Moreiras, Daniel, Patel, Priyaben, Lemmon, Mark, and Cardon, Catherine

Subjects
[SDU] Sciences of the Universe [physics]
Published
2022

11. Space Weather Services for Civil Aviation—Challenges and Solutions

Author

Kauristie, Kirsti, primary, Andries, Jesse, additional, Beck, Peter, additional, Berdermann, Jens, additional, Berghmans, David, additional, Cesaroni, Claudio, additional, De Donder, Erwin, additional, de Patoul, Judith, additional, Dierckxsens, Mark, additional, Doornbos, Eelco, additional, Gibbs, Mark, additional, Hammond, Krista, additional, Haralambous, Haris, additional, Harri, Ari-Matti, additional, Henley, Edmund, additional, Kriegel, Martin, additional, Laitinen, Tiera, additional, Latocha, Marcin, additional, Maneva, Yana, additional, Perrone, Loredana, additional, Pica, Emanuele, additional, Rodriguez, Luciano, additional, Romano, Vincenzo, additional, Sabbagh, Dario, additional, Spogli, Luca, additional, Stanislawska, Iwona, additional, Tomasik, Lukasz, additional, Tshisaphungo, Mpho, additional, van Dam, Kasper, additional, van den Oord, Bert, additional, Vanlommel, Petra, additional, Verhulst, Tobias, additional, Wilken, Volker, additional, Zalizovski, Andriy, additional, and Österberg, Kari, additional

Published
2021
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12. Meteorological Predictions for Mars 2020 Perseverance Rover Landing Site at Jezero Crater

Author

Pla-García, Jorge, Rafkin, Scot C. R., Martinez, G.M., Vicente-Retortillo, Álvaro, Newman, C.E., Savijärvi, H., de la Torre-Juárez, M., Rodríguez Manfredi, J.A., Gómez, F., Molina, A., Viúdez-Moreiras, Daniel, and Harri, Ari-Matti

Abstract

The Mars Regional Atmospheric Modeling System (MRAMS) and a nested simulation of the Mars Weather Research and Forecasting model (MarsWRF) are used to predict the local meteorological conditions at the Mars 2020 Perseverance rover landing site inside Jezero crater (Mars). These predictions are complemented with the COmplutense and MIchigan MArs Radiative Transfer model (COMIMART) and with the local Single Column Model (SCM) to further refine predictions of radiative forcing and the water cycle respectively. The primary objective is to facilitate interpretation of the meteorological measurements to be obtained by the Mars Environmental Dynamics Analyzer (MEDA) aboard the rover, but also to provide predictions of the meteorological phenomena and seasonal changes that might impact operations, from both a risk perspective and from the perspective of being better prepared to make certain measurements. A full diurnal cycle at four different seasons (L 0 , 90 , 180 , and 270 ) is investigated. Air and ground temperatures, pressure, wind speed and direction, surface radiative fluxes and moisture data are modeled. The good agreement between observations and modeling in prior works [Pla-Garcia et al. in Icarus 280:103–113, 2016; Newman et al. in Icarus 291:203–231, 2017; Vicente-Retortillo et al. in Sci. Rep. 8(1):1–8, 2018; Savijärvi et al. in Icarus, 2020] provides confidence in utilizing these models results to predict the meteorological environment at Mars 2020 Perseverance rover landing site inside Jezero crater. The data returned by MEDA will determine the extent to which this confidence was justified. With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)

Published
2020

13. AVAUS - Avaruuden uuden toimintaympäristön turvallisuusulottuvuudet ja liiketoiminta

Author

Harri, Ari-Matti, Liukkonen, Juha-Matti, Rowley, Christopher, Aaltola, Mika, Näsilä, Antti, and Huovelin, Juhani

Subjects
avaruus, turvallisuus, liiketoiminta, tutkimus, tutkimustoiminta, avaruusteknologian murros
Abstract

Avaruustoiminnalla on jo kauan ollut suuri strateginen merkitys yhteiskunnan toimivuudelle, kansalliselle turvallisuudelle ja eri hallinnonalojen päätöksenteolle. Yhteiskunnan toiminnot hyödyntävät satelliittien tuottamaa ja välittämää dataa, jonka määrä ja maantieteellinen kattavuus ovat laajentuneet radikaalisti viime vuosina. Aiemmin laajamittainen avaruustoiminta oli mahdollista vain suurilla taloudellisilla panostuksilla ja sitä harjoittivat vain muutamat maailman suurvallat. Nyt teknologinen kehitys ja avaruusteknologian halventuminen on mahdollistanut myös pienimuotoisemman avaruustoiminnan, jolla voidaan vastata tehokkaasti yhteiskunnan ja elinkeinoelämän tarpeisiin ja toiveisiin. Tämä mahdollistaa täysin uusia sovelluksia ja palveluita, jotka perustuvat avaruudesta ja Maan pinnalta tehtyjen havaintojen tehokkaaseen yhdistämiseen. Tämä on New Space -ilmiö, johon liittyvää liiketoimintaa kutsutaan nimellä New Space Economy – uusi avaruusliiketoiminta.Uuden avaruusteknologian ja sen tuomien sovellusmahdollisuuksien esiinmarssi ei ole korvaamassa perinteisellä avaruusteknologialla toteutettuja järjestelmiä. Tämä on oleellista. Uudet teknologiat sekä tuovat mukanaan uusia avaruuden hyödyntämismahdollisuuksia että täydentävät perinteisiä avaruusjärjestelmiä.Tämä tutkimus tarkastelee uutta avaruustoimintaympäristöä kansallisen hyödyntämisen kannalta: miten sen tarjoama yhteiskunnan turvallisuuteen vaikuttava teknologia sekä liiketoimintapotentiaali voitaisiin valjastaa parhaiten palvelemaan suomalaista yhteiskuntaa.Jos saamme luotua uutta teknistieteellistä kyvykkyyttä kansallisella perusrahoituksella, sillä on tärkeä vipuvaikutus sekä liiketoimintaan että suomalaisten turvallisuuteen. Osaaminen ja innovaatiot houkuttelevat kasvurahoitusta, mikä mahdollistaa liiketoiminnan nopean kasvun. Avaruuden turvallisuuskäyttö edellyttää korkealaatuista osaamista ja hyötyy menestyvästä liiketoiminnasta.Aktiivisilla toimilla Suomi pystyy hyödyntämään avaruusteknisen murroksen tarjoamat laajat liiketoiminnalliset mahdollisuudet sekä toisaalta varautumaan turvallisuuteen liittyviin uusiin haasteisiin. Toimenpidesuosituksemme ovat tämän mukaisia

Published
2020

15. CITYZER observation network and data delivery system

Author

Schmidt, Walter, primary, Harri, Ari-Matti, additional, Nousiainen, Timo, additional, Hohti, Harri, additional, Johansson, Lasse, additional, Ojanperä, Olli, additional, Viitala, Erkki, additional, Niemi, Jarkko, additional, Turpeinen, Jani, additional, Saukko, Erkka, additional, Rönkkö, Topi, additional, and Lahti, Pekka, additional

Published
2020
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21. The MetNet vehicle: a lander to deploy environmental stations for local and global investigations of Mars

Author

Harri, Ari-Matti, primary, Pichkadze, Konstantin, additional, Zeleny, Lev, additional, Vazquez, Luis, additional, Schmidt, Walter, additional, Alexashkin, Sergey, additional, Korablev, Oleg, additional, Guerrero, Hector, additional, Heilimo, Jyri, additional, Uspensky, Mikhail, additional, Finchenko, Valery, additional, Linkin, Vyacheslav, additional, Arruego, Ignacio, additional, Genzer, Maria, additional, Lipatov, Alexander, additional, Polkko, Jouni, additional, Paton, Mark, additional, Savijärvi, Hannu, additional, Haukka, Harri, additional, Siili, Tero, additional, Khovanskov, Vladimir, additional, Ostesko, Boris, additional, Poroshin, Andrey, additional, Diaz-Michelena, Marina, additional, Siikonen, Timo, additional, Palin, Matti, additional, Vorontsov, Viktor, additional, Polyakov, Alexander, additional, Valero, Francisco, additional, Kemppinen, Osku, additional, Leinonen, Jussi, additional, and Romero, Pilar, additional

Published
2017
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22. Evidence for indigenous nitrogen in sedimentary and aeolian deposits from the Curiosity rover investigations at Gale crater, Mars

Author

Stern, Jennifer C., Sutter, Brad, Freissinet, Caroline, Navarro-González, Rafael, McKay, Christopher P., Archer, P. Douglas, Buch, Arnaud, Brunner, Anna E., Coll, Patrice, Eigenbrode, Jennifer L., Fairen, Alberto G., Franz, Heather B., Glavin, Daniel P., Kashyap, Srishti, McAdam, Amy C., Ming, Douglas W., Steele, Andrew, Szopa, Cyril, Wray, James J., Martín-Torres, F. Javier, Zorzano, Maria-Paz, Conrad, Pamela G., Mahaffy, Paul R., Kemppinen, Osku, Bridges, Nathan, Johnson, Jeffrey R., Minitti, Michelle, Cremers, David, Bell, James F., Edgar, Lauren, Farmer, Jack, Godber, Austin, Wadhwa, Meenakshi, Wellington, Danika, McEwan, Ian, Newman, Claire, Richardson, Mark, Charpentier, Antoine, Peret, Laurent, King, Penelope, Blank, Jennifer, Weigle, Gerald, Schmidt, Mariek, Li, Shuai, Milliken, Ralph, Robertson, Kevin, Sun, Vivian, Baker, Michael, Edwards, Christopher, Ehlmann, Bethany, Farley, Kenneth, Griffes, Jennifer, Grotzinger, John, Miller, Hayden, Newcombe, Megan, Pilorget, Cedric, Rice, Melissa, Siebach, Kirsten, Stack, Katie, Stolper, Edward, Brunet, Claude, Hipkin, Victoria, Léveillé, Richard, Marchand, Geneviève, Sánchez, Pablo Sobrón, Favot, Laurent, Cody, George, Flückiger, Lorenzo, Lees, David, Nefian, Ara, Martin, Mildred, Gailhanou, Marc, Westall, Frances, Israël, Guy, Agard, Christophe, Baroukh, Julien, Donny, Christophe, Gaboriaud, Alain, Guillemot, Philippe, Lafaille, Vivian, Lorigny, Eric, Paillet, Alexis, Pérez, René, Saccoccio, Muriel, Yana, Charles, Armiens-Aparicio, Carlos, Rodríguez, Javier Caride, Blázquez, Isaías Carrasco, Gómez, Felipe Gómez, Gómez-Elvira, Javier, Hettrich, Sebastian, Malvitte, Alain Lepinette, Jiménez, Mercedes Marín, Martínez-Frías, Jesús, Martín-Soler, Javier, Torres, F. Javier Martín, Jurado, Antonio Molina, Mora-Sotomayor, Luis, Caro, Guillermo Muñoz, López, Sara Navarro, Peinado-González, Verónica, Pla-García, Jorge, Manfredi, José Antonio Rodriguez, Romeral-Planelló, Julio José, Fuentes, Sara Alejandra Sans, Martinez, Eduardo Sebastian, Redondo, Josefina Torres, Urqui-O'Callaghan, Roser, Mier, María-Paz Zorzano, Chipera, Steve, Lacour, Jean-Luc, Mauchien, Patrick, Sirven, Jean-Baptiste, Manning, Heidi, Fairén, Alberto, Hayes, Alexander, Joseph, Jonathan, Squyres, Steven, Sullivan, Robert, Thomas, Peter, Dupont, Audrey, Lundberg, Angela, Melikechi, Noureddine, Mezzacappa, Alissa, DeMarines, Julia, Grinspoon, David, Reitz, Günther, Prats, Benito, Atlaskin, Evgeny, Genzer, Maria, Harri, Ari-Matti, Haukka, Harri, Kahanpää, Henrik, Kauhanen, Janne, Paton, Mark, Polkko, Jouni, Schmidt, Walter, Siili, Tero, Fabre, Cécile, Wray, James, Wilhelm, Mary Beth, Poitrasson, Franck, Patel, Kiran, Gorevan, Stephen, Indyk, Stephen, Paulsen, Gale, Gupta, Sanjeev, Bish, David, Schieber, Juergen, Gondet, Brigitte, Langevin, Yves, Geffroy, Claude, Baratoux, David, Berger, Gilles, Cros, Alain, d’Uston, Claude, Forni, Olivier, Gasnault, Olivier, Lasue, Jérémie, Lee, Qiu-Mei, Maurice, Sylvestre, Meslin, Pierre-Yves, Pallier, Etienne, Parot, Yann, Pinet, Patrick, Schröder, Susanne, Toplis, Mike, Lewin, Éric, Brunner, Will, Heydari, Ezat, Achilles, Cherie, Oehler, Dorothy, Cabane, Michel, Coscia, David, Dromart, Gilles, Robert, François, Sautter, Violaine, Le Mouélic, Stéphane, Mangold, Nicolas, Nachon, Marion, Stalport, Fabien, François, Pascaline, Raulin, François, Teinturier, Samuel, Cameron, James, Clegg, Sam, Cousin, Agnès, DeLapp, Dorothea, Dingler, Robert, Jackson, Ryan Steele, Johnstone, Stephen, Lanza, Nina, Little, Cynthia, Nelson, Tony, Wiens, Roger C., Williams, Richard B., Jones, Andrea, Kirkland, Laurel, Treiman, Allan, Baker, Burt, Cantor, Bruce, Caplinger, Michael, Davis, Scott, Duston, Brian, Edgett, Kenneth, Fay, Donald, Hardgrove, Craig, Harker, David, Herrera, Paul, Jensen, Elsa, Kennedy, Megan R., Krezoski, Gillian, Krysak, Daniel, Lipkaman, Leslie, Malin, Michael, McCartney, Elaina, McNair, Sean, Nixon, Brian, Posiolova, Liliya, Ravine, Michael, Salamon, Andrew, Saper, Lee, Stoiber, Kevin, Supulver, Kimberley, Van Beek, Jason, Van Beek, Tessa, Zimdar, Robert, French, Katherine Louise, Iagnemma, Karl, Miller, Kristen, Summons, Roger, Goesmann, Fred, Goetz, Walter, Hviid, Stubbe, Johnson, Micah, Lefavor, Matthew, Lyness, Eric, Breves, Elly, Dyar, M. Darby, Fassett, Caleb, Blake, David F., Bristow, Thomas, DesMarais, David, Edwards, Laurence, Haberle, Robert, Hoehler, Tori, Hollingsworth, Jeff, Kahre, Melinda, Keely, Leslie, McKay, Christopher, Bleacher, Lora, Brinckerhoff, William, Choi, David, Conrad, Pamela, Dworkin, Jason P., Eigenbrode, Jennifer, Floyd, Melissa, Garvin, James, Glavin, Daniel, Harpold, Daniel, Mahaffy, Paul, Martin, David K., McAdam, Amy, Pavlov, Alexander, Raaen, Eric, Smith, Michael D., Stern, Jennifer, Tan, Florence, Trainer, Melissa, Meyer, Michael, Posner, Arik, Voytek, Mary, Anderson, Robert C, Aubrey, Andrew, Beegle, Luther W., Behar, Alberto, Blaney, Diana, Brinza, David, Calef, Fred, Christensen, Lance, Crisp, Joy A., DeFlores, Lauren, Feldman, Jason, Feldman, Sabrina, Flesch, Gregory, Hurowitz, Joel, Jun, Insoo, Keymeulen, Didier, Maki, Justin, Mischna, Michael, Morookian, John Michael, Parker, Timothy, Pavri, Betina, Schoppers, Marcel, Sengstacken, Aaron, Simmonds, John J., Spanovich, Nicole, Juarez, Manuel de la Torre, Vasavada, Ashwin R., Webster, Christopher R., Yen, Albert, Archer, Paul Douglas, Cucinotta, Francis, Jones, John H., Ming, Douglas, Morris, Richard V., Niles, Paul, Rampe, Elizabeth, Nolan, Thomas, Fisk, Martin, Radziemski, Leon, Barraclough, Bruce, Bender, Steve, Berman, Daniel, Dobrea, Eldar Noe, Tokar, Robert, Vaniman, David, Williams, Rebecca M. E., Yingst, Aileen, Lewis, Kevin, Leshin, Laurie, Cleghorn, Timothy, Huntress, Wesley, Manhès, Gérard, Hudgins, Judy, Olson, Timothy, Stewart, Noel, Sarrazin, Philippe, Grant, John, Vicenzi, Edward, Wilson, Sharon A., Bullock, Mark, Ehresmann, Bent, Hamilton, Victoria, Hassler, Donald, Peterson, Joseph, Rafkin, Scot, Zeitlin, Cary, Fedosov, Fedor, Golovin, Dmitry, Karpushkina, Natalya, Kozyrev, Alexander, Litvak, Maxim, Malakhov, Alexey, Mitrofanov, Igor, Mokrousov, Maxim, Nikiforov, Sergey, Prokhorov, Vasily, Sanin, Anton, Tretyakov, Vladislav, Varenikov, Alexey, Vostrukhin, Andrey, Kuzmin, Ruslan, Clark, Benton, Wolff, Michael, McLennan, Scott, Botta, Oliver, Drake, Darrell, Bean, Keri, Lemmon, Mark, Schwenzer, Susanne P., Anderson, Ryan B., Herkenhoff, Kenneth, Lee, Ella Mae, Sucharski, Robert, Hernández, Miguel Ángel de Pablo, Ávalos, Juan José Blanco, Ramos, Miguel, Kim, Myung-Hee, Malespin, Charles, Plante, Ianik, Muller, Jan-Peter, Ewing, Ryan, Boynton, William, Downs, Robert, Fitzgibbon, Mike, Harshman, Karl, Morrison, Shaunna, Dietrich, William, Kortmann, Onno, Palucis, Marisa, Sumner, Dawn Y., Williams, Amy, Lugmair, Günter, Wilson, Michael A., Rubin, David, Jakosky, Bruce, Balic-Zunic, Tonci, Frydenvang, Jens, Jensen, Jaqueline Kløvgaard, Kinch, Kjartan, Koefoed, Asmus, Madsen, Morten Bo, Stipp, Susan Louise Svane, Boyd, Nick, Campbell, John L., Gellert, Ralf, Perrett, Glynis, Pradler, Irina, VanBommel, Scott, Jacob, Samantha, Owen, Tobias, Rowland, Scott, Savijärvi, Hannu, Boehm, Eckart, Böttcher, Stephan, Burmeister, Sönke, Guo, Jingnan, Köhler, Jan, García, César Martín, Mueller-Mellin, Reinhold, Wimmer-Schweingruber, Robert, Bridges, John C., McConnochie, Timothy, Benna, Mehdi, Franz, Heather, Bower, Hannah, Brunner, Anna, Blau, Hannah, Boucher, Thomas, Carmosino, Marco, Atreya, Sushil, Elliott, Harvey, Halleaux, Douglas, Rennó, Nilton, Wong, Michael, Pepin, Robert, Elliott, Beverley, Spray, John, Thompson, Lucy, Gordon, Suzanne, Newsom, Horton, Ollila, Ann, Williams, Joshua, Vasconcelos, Paulo, Bentz, Jennifer, Nealson, Kenneth, Popa, Radu, Kah, Linda C., Moersch, Jeffrey, Tate, Christopher, Day, Mackenzie, Kocurek, Gary, Hallet, Bernard, Sletten, Ronald, Francis, Raymond, McCullough, Emily, Cloutis, Ed, ten Kate, Inge Loes, Arvidson, Raymond, Fraeman, Abigail, Scholes, Daniel, Slavney, Susan, Stein, Thomas, Ward, Jennifer, Berger, Jeffrey, Moores, John E., NASA Goddard Space Flight Center (GSFC), NASA Johnson Space Center (JSC), NASA, Laboratorio de Química de Plasmas y Estudios Planetarios [Mexico], Instituto de Ciencias Nucleares [Mexico], Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM)-Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), NASA Ames Research Center (ARC), Laboratoire de Génie des Procédés et Matériaux - EA 4038 (LGPM), CentraleSupélec, ASU School of Earth and Space Exploration (SESE), Arizona State University [Tempe] (ASU), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Department of Astronomy [Ithaca], Cornell University [New York], Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Center for Research and Exploration in Space Science and Technology [GSFC] (CRESST), Centre de Recherche Public Henri Tudor [Technoport] (CRP Henri Tudor), Centre de Recherche Public Henri-Tudor [Luxembourg] (CRP Henri-Tudor), Department of Microbiology [Amherst], University of Massachusetts [Amherst] (UMass Amherst), University of Massachusetts System (UMASS)-University of Massachusetts System (UMASS), Astromaterials Research and Exploration Science (ARES), NASA-NASA, Geophysical Laboratory [Carnegie Institution], Carnegie Institution for Science, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), School of Earth and Atmospheric Sciences [Atlanta], Georgia Institute of Technology [Atlanta], Instituto Andaluz de Ciencias de la Tierra (IACT), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad de Granada (UGR), Department of Computer Science, Electrical and Space Engineering [Luleå], Luleå University of Technology (LUT), Universidad Nacional Autónoma de México (UNAM)-Universidad Nacional Autónoma de México (UNAM), Carnegie Institution for Science [Washington], Universidad de Granada (UGR)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Cornell University, Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Department of Microbiology, IMPEC - LATMOS, Universidad de Granada (UGR)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), and Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad de Granada = University of Granada (UGR)

Subjects
Martian, Multidisciplinary, 010504 meteorology & atmospheric sciences, Water on Mars, nitrates, astrobiology, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Mars, Mars Exploration Program, 01 natural sciences, nitrogen, Astrobiology, Curiosity, 13. Climate action, Rocknest, 0103 physical sciences, Sample Analysis at Mars, Physical Sciences, Aeolian processes, Composition of Mars, 010303 astronomy & astrophysics, Nitrogen cycle, Geology, 0105 earth and related environmental sciences
Abstract

International audience; The Sample Analysis at Mars (SAM) investigation on the Mars Science Laboratory (MSL) Curiosity rover has detected oxidized nitrogen-bearing compounds during pyrolysis of scooped aeolian sediments and drilled sedimentary deposits within Gale crater. Total N concentrations ranged from 20 to 250 nmol N per sample. After subtraction of known N sources in SAM, our results support the equivalent of 110–300 ppm of nitrate in the Rocknest (RN) aeolian samples, and 70–260 and 330–1,100 ppm nitrate in John Klein (JK) and Cumberland (CB) mudstone deposits, respectively. Discovery of indigenous martian nitrogen in Mars surface materials has important implications for habitability and, specifically, for the potential evolution of a nitrogen cycle at some point in martian history. The detection of nitrate in both wind-drifted fines (RN) and in mudstone (JK, CB) is likely a result of N2 fixation to nitrate generated by thermal shock from impact or volcanic plume lightning on ancient Mars. Fixed nitrogen could have facilitated the development of a primitive nitrogen cycle on the surface of ancient Mars, potentially providing a biochemically accessible source of nitrogen.

Published
2015

23. Diurnal variations of energetic particle radiation at the surface of Mars as observed by the Mars Science Laboratory Radiation Assessment Detector

Author

Rafkin, Scot C. R., Zeitlin, Cary, Ehresmann, Bent, Hassler, Donald M., Guo, Jingnan, Köhler, Jan, Wimmer-Schweingruber, Robert F., Gómez-Elvira, Javier, Harri, Ari-Matti, Kahanpää, Henrik, Brinza, David E., Weigle, Gerald, Böttcher, Stephan, Böhm, Eckart, Burmeister, Söenke, Martín, César, Reitz, Güenther, Cucinotta, Francis A., Kim, Myung-Hee, Grinspoon, David, Bullock, Mark A., Posner, Arik, MSL Science Team, and Martínez-Frías, J.

Subjects
Physics, Radiation, Meteorology, Space weather, Atmosphere, Mars, Mars Science Laboratory, Mars Exploration Program, Atmospheric sciences, Radiation assessment detector, Physics::Geophysics, Computer Science::Robotics, Geophysics, Space and Planetary Science, Geochemistry and Petrology, Diurnal cycle, Thermal, Physics::Space Physics, Earth and Planetary Sciences (miscellaneous), Astrophysics::Earth and Planetary Astrophysics, Particle radiation, Neutral particle
Abstract

The Radiation Assessment Detector onboard the Mars Science Laboratory rover Curiosity is detecting the energetic particle radiation at the surface of Mars. Data collected over the first 350 Martian days of the nominal surface mission show a pronounced diurnal cycle in both the total dose rate and the neutral particle count rate. The diurnal variations detected by the Radiation Assessment Detector were neither anticipated nor previously considered in the literature. These cyclic variations in dose rate and count rate are shown to be the result of changes in atmospheric column mass driven by the atmospheric thermal tide that is characterized through pressure measurements obtained by the Rover Environmental Monitoring Station, also onboard the rover. In addition to bulk changes in the radiation environment, changes in atmospheric shielding forced by the thermal tide are shown to disproportionately affect heavy ions compared to H and He nuclei.

Published
2014

24. Comparison of Martian surface ionizing radiation measurements from MSL-RAD with Badhwar-O'Neill 2011/HZETRN model calculations

Author

Kim, Myung-Hee, Cucinotta, Francis A., Nounu, Hatem N., Zeitlin, Cary, Hassler, Donald M., Rafkin, Scot C. R., Wimmer-Schweingruber, Robert F., Ehresmann, Bent, Brinza, David E., Böttcher, Stephan, Böhm, Eckart, Burmeister, Söenke, Guo, Jingnan, Köhler, Jan, Martín, César, Reitz, Güenther, Posner, Arik, Gómez-Elvira, Javier, Harri, Ari-Matti, MSL Science Team, and Martínez-Frías, J.

Subjects
Physics, Martian, Equivalent dose, Radiation transport, Cosmic ray, Mars Exploration Program, Atmosphere of Mars, Atmospheric sciences, Computational physics, Geophysics, Space and Planetary Science, Geochemistry and Petrology, Martian surface, Earth and Planetary Sciences (miscellaneous), Dose rate on Martian surface, Dosimetry, Neutron, Galactic cosmic radiation
Abstract

Dose rate measurements from Mars Science Laboratory-radiation assessment detector (MSL-RAD) for 300 sols on Mars are compared to simulation results using the Badhwar-O'Neill 2011 galactic cosmic ray (GCR) environment model and the high-charge and energy transport (HZETRN) code. For the nuclear interactions of primary GCR through Mars atmosphere and Curiosity rover, the quantum multiple scattering theory of nuclear fragmentation is used. Daily atmospheric pressure is measured at Gale Crater by the MSL Rover Environmental Monitoring Station. Particles impinging on top of the Martian atmosphere reach RAD after traversing varying depths of atmosphere that depend on the slant angles, and the model accounts for shielding of the RAD “E” detector (used for dosimetry) by the rest of the instrument. Simulation of average dose rate is in good agreement with RAD measurements for the first 200 sols and reproduces the observed variation of surface dose rate with changing heliospheric conditions and atmospheric pressure. Model results agree less well between sols 200 and 300 due to subtleties in the changing heliospheric conditions. It also suggests that the average contributions of albedo particles (charge number Z

Published
2014

25. Pressure observations by the Curiosity rover: Initial results

Author

Harri, Ari-Matti, Genzer, Maria, Kemppinen, O., Kahanpää, Henrik, Gómez-Elvira, Javier, Rodríguez-Manfredi, José Antonio, Haberle, Robert, Polkko, Jouni, Schmidt, W., Savijärvi, H., Kauhanen, J., Atlaskin, E., Richardson, Mark, Siili, T., Paton, M., Torre Juárez, Manuel de la, Newman, C., Rafkin, Scot C. R., Lemmon, M., Mischna, Michael, Merikallio, S., Haukka, H., Martín-Torres, F. J., Zorzano, María Paz, Peinado, Verónica, Urquí, Roser, Lapinette, A., Scodary, A., Mäkinen, T., Vázquez, L., Rennó, Nilton O., MSL Science Team, and Martínez-Frías, J.

Subjects
Pressure drop, Martian, Meteorology, Atmosphere, Mars, Mars Exploration Program, Atmosphere of Mars, Atmospheric sciences, Surface pressure, law.invention, Geophysics, Pressure measurement, 13. Climate action, Space and Planetary Science, Geochemistry and Petrology, law, Diurnal tide, Thermal, Earth and Planetary Sciences (miscellaneous), Geology, Sensor
Abstract

REMS-P, the pressure measurement subsystem of the Mars Science Laboratory (MSL) Rover Environmental Measurement Station (REMS), is performing accurate observations of the Martian atmospheric surface pressure. It has demonstrated high data quality and good temporal coverage, carrying out the first in situ pressure observations in the Martian equatorial regions. We describe the REMS-P initial results by MSL mission sol 100 including the instrument performance and data quality and illustrate some initial interpretations of the observed features. The observations show both expected and new phenomena at various spatial and temporal scales, e.g., the gradually increasing pressure due to the advancing Martian season signals from the diurnal tides as well as various local atmospheric phenomena and thermal vortices. Among the unexpected new phenomena discovered in the pressure data are a small regular pressure drop at every sol and pressure oscillations occurring in the early evening. We look forward to continued high-quality observations by REMS-P, extending the data set to reveal characteristics of seasonal variations and improved insights into regional and local phenomena.

Published
2014

26. Preliminary interpretation of the REMS pressure data from the first 100 sols of the MSL mission

Author

Haberle, Robert, Gómez-Elvira, Javier, Torre Juárez, Manuel de la, Harri, Ari-Matti, Hollingsworth, J. L., Kahanpää, Henrik, Kahre, M. A., Lemmon, M., Martín-Torres, F. J., Mischna, Michael, Moores, J. E., Newman, C., Rafkin, Scot C. R., Rennó, Nilton O., Richardson, Mark, Rodríguez-Manfredi, José Antonio, Vasavada, Ashwin R., Zorzano, María Paz, MSL Science Team, and Martínez-Frías, J.

Subjects
Pressure, MSL, REMS
Abstract

We provide a preliminary interpretation of the Rover Environmental Monitoring Station (REMS) pressure data from the first 100 Martian solar days (sols) of the Mars Science Laboratory mission. The pressure sensor is performing well and has revealed the existence of phenomena undetected by previous missions that include possible gravity waves excited by evening downslope flows, relatively dust-free convective vortices analogous in structure to dust devils, and signatures indicative of the circulation induced by Gale Crater and its central mound. Other more familiar phenomena are also present including the thermal tides, generated by daily insolation variations, and the CO2 cycle, driven by the condensation and sublimation of CO2 in the polar regions. The amplitude of the thermal tides is several times larger than those seen by other landers primarily because Curiosity is located where eastward and westward tidal modes constructively interfere and also because the crater circulation amplifies the tides to some extent. During the first 100 sols tidal amplitudes generally decline, which we attribute to the waning influence of the Kelvin wave. Toward the end of the 100 sol period, tidal amplitudes abruptly increased in response to a nearby regional dust storm that did not expand to global scales. Tidal phases changed abruptly during the onset of this storm suggesting a change in the interaction between eastward and westward modes. When compared to Viking Lander 2 data, the REMS daily average pressures show no evidence yet for the 1–20 Pa increase expected from the possible loss of CO2 from the south polar residual cap.

Published
2014

28. Phobos eclipse detection on Mars : theory and practice

Author

Harri, Ari-Matti, Schmidt, Walter, Romero, Pilar, Vázquez, Luis, Barderas, Gonzalo, Kemppinen, Osku, Aguirre, Carlos, Vázquez-Poleti, Jose Luis, Llorente, Ignacio M., Haukka, Harri, and Paton, Mark

Subjects
Viking, cloud computing, MetNet, tomography, Phobos eclipses
Abstract

We present a general approach to study solar eclipses by Phobos on Mars: its parameterization and prediction.The validation of the model and the involved parameters is made with the already observed eclipses by previous Mars missions. Eclipse prediction is applied for the past Mars lander missions: Viking, Pathfinder and Phoenix, as well as for the future Mars MetNet Precursor Mission. A successful detection of eclipses could be used for the localization of landers and to study atmospheric properties. We also consider the data analysis, with special emphasis in the tomographic method to identify events which are very localized in space and time. Large computation requirements are needed for the implemented methods. To this propose an efficient Cloud Computing Network Infrastructure has been used. Esittelemme yleisen lähestymistavan Phoboksen auringonpimennysten tutkimiseen, parametrisointiin ja ennustamiseen. Mallin ja sen parametrien validointi tehdään menneiden ja nykyisten Mars-missioiden havaitsemien pimennysten avulla. Pimennysten ennustamista käytetään menneisiin Viking-, Pathfinder- ja Phoenix-laskeutujiin, samoin kuin tulevaan Mars MetNet Precursor missioon. Pimennysten onnistuneita havaintoja voitaisiin käyttää laskeutujien paikantamiseen ja kaasukehän ominaisuuksien tutkimiseen. Käsittelemme myös data-analyysiä, painottaen erityisesti tomografiamenetelmää, havaitaksemme tapahtumia jotka ovat paikallisia ajan ja sijainnin suhteen. Menetelmien toteuttamiseen vaaditaan suuri laskentakapasiteetti. Tämän toteuttamiseen on käytetty pilvilaskentaa.

Published
2012

29. Waves and acceleration of relativistic particles (WARP)

Author

Pulkkinen, Tuija, Harri, Ari-Matti, Haukka, Harri, Leinonen, Jussi, Toivanen, Petri, Koskinen, Hannu, Andé, Mats, Balasis, Georgios, Boscher, Daniel, Dandouras, Iannis, Grande, Manuel, De Keysier, Johan, Glassmeier, Karl-Heinz, Hapgood, Mike, Horne, Richard, Ivchenko, Nikolay, Santolik, Ondrej, Tokar, Klaus, Trotignon, Jean Gabriel, Vennerstom, Susanne, Finnish Meteorological Institute, Ilmatieteen laitos, and Meteorologiska Institutet

Subjects
säteilyvyöt, satellittimissiot, spacecraft missions, spacecraft, magnetosfääri, magentosphere, radiation belt, satellitit
Published
2007

30. Microphysical Properties of Snow and Their Link to Z e- S Relations during BAECC 2014.

Author

von Lerber, Annakaisa, Moisseev, Dmitri, Bliven, Larry F., Petersen, Walter, Harri, Ari-Matti, and Chandrasekar, V.

Subjects
MICROPHYSICS, REMOTE sensing, RADAR meteorology, CLIMATE change, METEOROLOGICAL precipitation
Abstract

This study uses snow events from the Biogenic Aerosols-Effects on Clouds and Climate (BAECC) 2014 campaign to investigate the connection between properties of snow and radar observations. The general hydrodynamic theory is applied to video-disdrometer measurements to retrieve masses of falling ice particles. Errors associated with the observation geometry and the measured particle size distribution (PSD) are addressed by devising a simple correction procedure. The value of the correction factor is determined by comparison of the retrieved precipitation accumulation with weighing-gauge measurements. Derived mass-dimensional relations are represented in the power-law form m = . It is shown that the retrieved prefactor a m and exponent b m react to changes in prevailing microphysical processes. From the derived microphysical properties, event-specific relations between the equivalent reflectivity factor Z e and snowfall precipitation rate S ( Z e = ) are determined. For the studied events, the prefactor of the Z e- S relation varied between 53 and 782 and the exponent was in the range of 1.19-1.61. The dependence of the factors a zs and b zs on the m( D) relation and PSD are investigated. The exponent of the Z e- S relation mainly depends on the exponent of the m( D) relation, whereas the prefactor a zs depends on both the intercept parameter N0 of the PSD and the prefactors of the m( D) and υ( D) relations. Changes in a zs for a given N0 are shown to be linked to changes in liquid water path, which can be considered to be a proxy for degree of riming. [ABSTRACT FROM AUTHOR]

Published
2017
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34. A user-orientated column modelling framework for efficient analyses of the Martian atmosphere.

Author

Paton, Mark, Harri, Ari-Matti, Vierkens, Oliver, and Savijärvi, Hannu

Subjects
*MARTIAN atmosphere, *GRAPHICAL user interfaces, *COMPOSITE columns, *SURFACE pressure, *SURFACE temperature
Abstract

As spacecraft return ever more data from Mars an increasingly integrated approach will be required to efficiently explore and analyse these data sets. Vast amounts of data already exist from soundings of the Martian atmosphere by spacecraft instruments, e.g. Mars Climate Sounder, providing snapshots during the evolution of the Martian climate. Temperature can be particularly useful, as a diagnostic tool for understanding Martian weather, as it is sensitive to a wide range of processes.To streamline research into the atmosphere of Mars a user-orientated modelling capability is developed that enables automatic initialisation and running of a column model. This model can be initialised using headers from the soundings data and compared to a selection of temperature profiles filtered using a graphical user interface. The soundings data can itself be independently queried, via a command line, to explore and extract the temperature data or any other associated information. As a demonstration we utilise the modelling framework to provide additional verification for the University of Helsinki/Finnish Meteorological Institute Mars column model at the higher altitudes. We also utilise the framework to understand the model's applicability, and identify opportunities for modifications/research, within the context of atmospheric processes that occur over large horizontal distances. We allow the software wrapper to automatically initialise the model with values either from the soundings data itself or other sources. These properties include surface temperature, surface pressure, dust opacity, thermal inertia and albedo. Locations on Mars that are well characterised and cover a range of latitudes are explored, e.g. landing sites such as Curiosity, Viking lander 1 and Viking lander 2. [ABSTRACT FROM AUTHOR]

Published
2019

35. MetNet Mission for Mars – Current Status and Future Prospects.

Author

Nikkanen, Timo, Harri, Ari-Matti, Aleksashkin, Sergey, Arruego, Ignacio, Schmidt, Walter, Genzer, Maria, Vazquez, Luis, and Haukka, Harri

Subjects
*MARTIAN exploration, *MARTIAN surface, *MECHANICAL shock, *MARS (Planet), *RADIO antennas, *IMPACT craters
Abstract

A new kind of planetary exploration mission for Mars is under development in collaboration between the FMI, LA, IKI and INTA. The Mars MetNet mission is based on a new semi-hard landing vehicle called MetNet Lander.The scientific payload of the mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide significant insights in to the Martian atmospheric behavior. The key technologies of the MetNet Lander have been qualified and the electrical qualification model of the payload bay has been built and successfully tested. IntroductionMetNet Lander:The MetNet landing vehicles are using an inflatable entry and descent system instead of rigid heat shields and parachutes as earlier semi-hard landing devices have used. This way the ratio of the payload mass to the overall mass is optimized. The landing impact will burrow the payload container into the Martian soil providing a more favorable thermal environment for the electronics and a suitable orientation of the telescopic boom with external sensors and the radio link antenna. It is planned to deploy several tens of MNLs on the Martian surface operating at least partly at the same time to allow meteorological network science.The descent processes dynamic properties are monitored by a special 3-axis accelerometer with a 3-axis gyrometer. The data will be sent via auxiliary beacon antenna throughout the descent phase starting shortly after separation from the spacecraft. MetNet Mission payload instruments are specially designed to operate under very low power conditions. MNL flexible solar panels provides a total of approximately 0.7-0.8W of electric power during the daylight time. As the provided power output is insufficient to operate all instruments simultaneously they are activated sequentially according to a specially designed cyclogram table which adapts itself to the different environmental constraints.Mission Status:Full Qualification Model of the MetNet landing unit with the Precursor Mission payload is currently under functional tests. In the near future the QM unit will be exposed to environmental tests with qualification levels including vibrations, thermal balance, thermal cycling and mechanical impact shock. One complete flight unit of the entry, descent and landing systems has been manufactured and tested with acceptance levels. Another flight-like EDLS has been exposed to most of the qualification tests, and hence it may be used for flight after refurbishments. Accordingly two flight-capable EDLS systems exist. The eventual goal is to create a network of atmospheric observational posts around the Martian surface. Even if the MetNet mission is focused on the atmospheric science, the mission payload will also include additional kinds of geophysical instrumentation. The next step in the MetNet Precursor Mission is the demonstration of the technical robustness and scientific capabilities of the MetNet type of landing vehicle. Definition of the Precursor Mission and discussions on launch opportunities are currently under way. The baseline program development funding exists for the next five years. Flight unit manufacture of the payload bay takes about 18 months, and it will be commenced after the Precursor Mission has been defined [ABSTRACT FROM AUTHOR]

Published
2019

36. Three full martian years of in situ humidity at Gale crater through MSL/REMS observations.

Author

Harri, Ari-Matti, Genzer, Maria, Gomez-Elvira, Javier, Savijarvi, Hannu, McConnochie, Timothy, Hieta, Maria, De la Torre, Manuel, Polkko, Jouni, Martinez, German, Nikkanen, Timo, Paton, Mark, and Vazquez, Luis

Subjects
*GALE Crater (Mars), *ATMOSPHERIC pressure, *HYDROLOGIC cycle, *ATMOSPHERIC temperature, *EARTH temperature, *HUMIDITY
Abstract

Mars Science laboratory (MSL) has been operating successfully since early August 2012 with the REMS instrument providing extremely valuable atmospheric observations of atmospheric pressure, temperature of the air, ground temperature, wind speed and direction, relative humidity (REMS-H), and UV measurements.The REMS-H relative humidity device is based on polymeric capacitive humidity sensors developed by Vaisala Inc. and it makes use of three (3) humidity sensor heads. The humidity device is mounted on the REMS boom providing ventilation with the ambient atmosphere through a filter protecting the device from airborne dust. The REMS-H humidity instrument has created an unprecedented data record of more than two full Martian years.It has measured the relative humidity and temperature at 1.6 m height for a period of 5 minutes every hour as part of the MSL/REMS instrument package. Mars Science laboratory (MSL) has been operating successfully since early August 2012 with the REMS instrument providing extremely valuable atmospheric observations of atmospheric pressure, temperature of the air, ground temperature, wind speed and direction, relative humidity (REMS-H), and UV measurements.The annual in situ water cycle based on three full Martian years at the Gale crater will be discussed. We will utilize the REMS-H instrument's in situ observations accompanied by orbital observations and modeling efforts. We will infer the hourly atmospheric VMR from the REMS-H observations and compare these VMR measurements with predictions of VMR given by our 1D column Martian atmospheric/regolith model to investigate the local water cycle, exchange processes and the local climate in Gale Crater.The strong diurnal variation suggests there are surface-atmosphere exchange processes at Gale Crater during all seasons, which deplete moisture to the ground in the evening and nighttime and release the moisture back to the atmosphere during the daytime. Our modeling results presumably indicate that adsorption processes take place during the nighttime and desorption during the daytime. Other processes, e.g. convective turbulence play a significant role in the daytime in conveying the moisture into the atmosphere. A clear increase in the amount of early morning atmospheric humidity was detected from about sol 1800 onward, when Curiosity started to climb onto Mt. Sharp. The MSL MastCam pictures from this time show exposed bedrock scenery with very sparse and thin layers of wind-blown dust. Our simulations indicate that a plausible explanation for the increase of the atmospheric humidity during early mornings could be the Mt Sharp bedrock material a higher inertia low porosity of an exposed bedrock material. [ABSTRACT FROM AUTHOR]

Published
2019

37. Ionosphere and arctic research with Suomi100 nanosatellite.

Author

Kallio, Esa, Harri, Ari-Matti, Aikio, Anita, Alho, Markku, Fontell, Mathias, Jarvinen, Riku, Kauristie, Kirsti, Kestilä, Antti, Turunen, Esa, Vanhamäki, Heikki, Norberg, Johannes, Koskimaa, Petri, Alho, Arno, Knuuttila, Olli, and Rynö, Jouni

Subjects
*IONOSPHERE, *PLASMA sheaths, *NANOSATELLITES, *RADIO wave propagation, *ELECTROMAGNETIC wave propagation, *RADIO waves, *SPATIO-temporal variation, *ELECTROMAGNETIC waves
Abstract

The Suomi100 nanosatellite was launched on Dec. 3, 2018 (http://www.suomi100satelliitti.fi/eng). The 1 Unit (10 cm x 10 cm x 10 cm) polar orbit cubesat will perform geospace, ionosphere and arctic region research with a white light camera and a radio wave spectrometer instrument which operates in the 1-10 MHz frequency range.The Suomi 100 satellite is a manifestation of a modern technology that provides new possibilities to study Earth's ionosphere by using small spacecraft and 3D computer simulations. Suomi 100 satellite type of nanosatellite, so called CubeSat, provides a cost effective possibility to provide in-situ measurements in the ionosphere. Moreover, combined CubeSat observations with ground-based observations give a new view on auroras and associated electromagnetic phenomena. Especially joint CubeSat – ground based observation campaigns enable the possibility of studying the 3D structure of the ionosphere.At the same time, increasing computation capacity has made it possible to perform simulations where properties of the ionosphere, such as propagation of the electromagnetic waves in the medium frequency, MF (0.3-3 MHz) and high frequency, HF (3-30 MHz), ranges is based on a 3D ionosphere model and on first-principles modelling. Electromagnetic waves at those frequencies are strongly affected by ionospheric electrons and, consequently, those frequencies can be used for studying the plasma. On the other hand, even if the ionosphere originally enables long-range telecommunication at MF and HF frequencies, the frequent occurrence of spatio-temporal variations in the ionosphere disturbs communication channels, especially at high latitudes. Therefore, study of the MF and HF waves in the ionosphere has both a strong science and technology interests.We present computational simulation and measuring principles and techniques to investigate the arctic ionosphere by a polar orbiting CubeSat which radio instrument measures HF and MF waves. We introduce 3D simulations, which have been developed to study the propagation of the radio waves, both ground generated man-made radio waves and space formed space weather related waves, through the 3D arctic ionosphere with a 3D ray tracing simulation and a local scale full kinetic electromagnetic simulation. We also introduce the Suomi100 CubeSat mission and its initial observations. [ABSTRACT FROM AUTHOR]

Published
2019

39. WinterWeather - Probabilistic Nowcasting to increase airport safety and capacity.

Author

Haukka, Harri, Harri, Ari-Matti, Kaltenboeck, Rudolf, Hagen, Martin, Saltikoff, Elena, Pulkkinen, Seppo, Juntti, Heikki, Pumpel, Herbert, Steinheimer, Martin, Österberg, Kari, von Lerber, Annakaisa, Hohti, Harri, Riihisaari, Tarja, Nuottokari, Jaakko, Peura, Markus, and Lehkonen, Aulikki

Subjects
*AIRPORT capacity, *AIRPORT safety, *WEATHER, *AIR traffic
Abstract

We describe the intermediate results of a SJU/EU -funded research activity, called Probabilistic Nowcasting of Winter Weather for Airports (PNOWWA), developing methods to support the Air Traffic Management (ATM) challenged by winter weather. Our methodology is based on probabilistic nowcasting of winter weather, which will enable the estimation of winter weather conditions affecting the ground part of air traffic 4D trajectories. This kind of ATM methods and tools are called for, because the uncertainties during flight, departure and arrival at airports create a need to effectively utilize probability forecasts, both in the local operational user environment and en-route. [ABSTRACT FROM AUTHOR]

Published
2018

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