Episode 351 - A new dwarf planet and what makes an exoplanet habitable

What makes a dwarf planet not a planet? What are the rules governing the word planet? Just how many dwarf planets are out there in our solar system? How can we use telescopes and modelling to add or subtract a dwarf planet from that list? We've talked about Goldilocks zone exoplanets, but what about their ability to withstand space weather? What role does a star's magnetic field play in protecting a planet from damaging radiation? Does space weather need to be added to the exoplanet Goldilocks zone?

References:

1. P. Vernazza, L. Jorda, P. Ševeček, M. Brož, M. Viikinkoski, J. Hanuš, B. Carry, A. Drouard, M. Ferrais, M. Marsset, F. Marchis, M. Birlan, E. Podlewska-Gaca, E. Jehin, P. Bartczak, G. Dudzinski, J. Berthier, J. Castillo-Rogez, F. Cipriani, F. Colas, F. DeMeo, C. Dumas, J. Durech, R. Fetick, T. Fusco, J. Grice, M. Kaasalainen, A. Kryszczynska, P. Lamy, H. Le Coroller, A. Marciniak, T. Michalowski, P. Michel, N. Rambaux, T. Santana-Ros, P. Tanga, F. Vachier, A. Vigan, O. Witasse, B. Yang, M. Gillon, Z. Benkhaldoun, R. Szakats, R. Hirsch, R. Duffard, A. Chapman, J. L. Maestre. A basin-free spherical shape as an outcome of a giant impact on asteroid Hygiea. Nature Astronomy, 2019; DOI: 10.1038/s41550-019-0915-8
2. Alison O. Farrish, David Alexander, Mei Maruo, Marc DeRosa, Frank Toffoletto, Anthony M. Sciola. Characterizing the Magnetic Environment of Exoplanet Stellar Systems. The Astrophysical Journal, 2019; 885 (1): 51 DOI: 10.3847/1538-4357/ab4652

Episode 347 - Capturing carbon with better farms and forests

Capturing carbon is important for helping offset CO2 emissions and tackling climate changes. Farming has an important role to play in improving CO2 sequestration with the use of cover crops and compost. Forests are important carbon sinks too, but they are at risk releasing a lot of the trapped carbon if care is not taken to stop invasive species. Plus fertilisers have helped feed the planet but can leech out nitrogen into the environment, so how do we better manage and improve the nitrogen cycle.

1. Nicole E. Tautges, Jessica L. Chiartas, Amélie C. M. Gaudin, Anthony T. O'Geen, Israel Herrera, Kate M. Scow. Deep soil inventories reveal that impacts of cover crops and compost on soil carbon sequestration differ in surface and subsurface soils. Global Change Biology, 2019; DOI: 10.1111/gcb.14762
2. Songlin Fei, Randall S. Morin, Christopher M. Oswalt, Andrew M. Liebhold. Biomass losses resulting from insect and disease invasions in US forests. Proceedings of the National Academy of Sciences, 2019; 201820601 DOI: 10.1073/pnas.1820601116
3. Benjamin Z. Houlton, Maya Almaraz, Viney Aneja, Amy T. Austin, Edith Bai, Kenneth G. Cassman, Jana E. Compton, Eric A. Davidson, Jan Willem Erisman, James N. Galloway, Baojing Gu, Guolin Yao, Luiz A. Martinelli, Kate Scow, William H. Schlesinger, Thomas P. Tomich, Chao Wang, Xin Zhang. A World of Cobenefits: Solving the Global Nitrogen Challenge. Earth's Future, 2019; DOI: 10.1029/2019EF001222

Episode 335 - Oceans, ocean size algae, deserts and fresh water in strange places

Water, water everywhere but not a drop to drink or nutrient for that matter. The Ocean can sometimes be a inhospitable place with barely any nutrients to survive off. Other times it can be home to large ocean spanning algae blooms. The oceans from the Pacific to the Atlantic can hold lots of secrets (even fresh water) beneath the surface. This week we look at 3 different papers which outline strange parts of the ocean, from large algae blooms to hidden aquifers.

References:

1. Greta Reintjes, Halina E. Tegetmeyer, Miriam Bürgisser, Sandi Orlić, Ivo Tews, Mikhail Zubkov, Daniela Voß, Oliver Zielinski, Christian Quast, Frank Oliver Glöckner, Rudolf Amann, Timothy G. Ferdelman, Bernhard M. Fuchs. On-Site Analysis of Bacterial Communities of the Ultraoligotrophic South Pacific Gyre. Applied and Environmental Microbiology, 2019; 85 (14) DOI: 10.1128/AEM.00184-19
2. Mengqiu Wang, Chuanmin Hu, Brian B. Barnes, Gary Mitchum, Brian Lapointe, Joseph P. Montoya. The great Atlantic Sargassum belt. Science, 2019; 365 (6448): 83 DOI: 10.1126/science.aaw7912
3. Chloe Gustafson, Kerry Key, Rob L. Evans. Aquifer systems extending far offshore on the U.S. Atlantic margin. Scientific Reports, 2019; 9 (1) DOI: 10.1038/s41598-019-44611-7

Episode 320 - Extinction events and their causes

Life has been around on earth for a long time, but there have been many extinction events that have wiped out large numbers of species. This week we find out how scientists peel back the layers of rock to uncover what caused these extinction events. Plus we find out about current extinction events and what we can learn from the past to protect species today.

References:

1. DePalma, Robert A.; Smit, Jan; Burnham, David; Kuiper, Klaudia; Manning, Phillip; Oleinik, Anton; Larson, Peter; Maurrasse, Florentin; Vellekoop, Johan; Richards, Mark A.; Gurche, Loren; Alvarez, Walter. Prelude to Extinction: a seismically induced onshore surge deposit at the KPg boundary, North Dakota. PNAS, 2019
2. Ben C. Scheele et al. Amphibian fungal panzootic causes catastrophic and ongoing loss of biodiversity. Science, 2019 DOI: 10.1126/science.aav0379
3. Seth A. Young, Andrew Kleinberg, Jeremy D. Owens. Geochemical evidence for expansion of marine euxinia during an early Silurian (Llandovery–Wenlock boundary) mass extinction. Earth and Planetary Science Letters, 2019; 513: 187 DOI: 10.1016/j.epsl.2019.02.023

Episode 319 - Changing lakes and rivers in the Antarctic and Arctic. Plus carbon capture and storage

Trying to understand how the climate will change is difficult. For every big event like the break up of an ice shelf, there are thousands of little factors that play a role. Sometimes this little things turn into a torrent of a river, or a calm lake which can cause an entire continent to bend and flex. We find out about research into the Arctic Tundra and it's changing lakes which are one of the largest natural emitters of greenhouse gases. Plus ways to capture greenhouse gases and store them safely.

References:

1. Alison F. Banwell, Ian C. Willis, Grant J. Macdonald, Becky Goodsell, Douglas R. MacAyeal. Direct measurements of ice-shelf flexure caused by surface meltwater ponding and drainage. Nature Communications, 2019; 10 (1) DOI: 10.1038/s41467-019-08522-5
2. Sarah W. Cooley, Laurence C. Smith, Jonathan C. Ryan, Lincoln H. Pitcher, Tamlin M. Pavelsky. Arctic‐Boreal lake dynamics revealed using CubeSat imagery. Geophysical Research Letters, 2019; DOI: 10.1029/2018GL081584
3. Fundação de Amparo à Pesquisa do Estado de São Paulo. (2019, February 13). Carbon gas storage cavern is the best way to obtain clean energy from a fossil fuel. ScienceDaily. Retrieved February 15, 2019 from www.sciencedaily.com/releases/2019/02/190213124358.htm

Episode 315 - Asteroids, meteorites and the destruction of moons

It's easy to think of the solar system as a static object that's always been there. But by studying asteroids, meteorites and moons we can piece together the often violent and dramatic history of our solar system. From Earth being bombarded by water bearing asteroids, to moons being broken apart and reformed around Neptune. We even follow up on some of the great work done by JAXA and the Hyabusa 2 mission. This week we look at some of the latest research into our solar system by studying the smallest often overlooked pieces.

References:

1. Josep M. Trigo-Rodríguez, Albert Rimola, Safoura Tanbakouei, Victoria Cabedo Soto, Martin Lee. Accretion of Water in Carbonaceous Chondrites: Current Evidence and Implications for the Delivery of Water to Early Earth. Space Science Reviews, 2019; 215 (1) DOI: 10.1007/s11214-019-0583-0
2. Rincon, P. (2019, February 21). Hayabusa-2: Japan mission set to 'bite an asteroid'. Retrieved from https://www.bbc.com/news/science-environment-47293317
3. M. R. Showalter, I. de Pater, J. J. Lissauer, R. S. French. The seventh inner moon of Neptune. Nature, 2019; 566 (7744): 350 DOI: 10.1038/s41586-019-0909-9

Episode 314 - Ancient life and life in extreme places

From the bottom of the ocean, to the earliest days of the earth, life has managed to not just survive but thrive. We look at several cases which change our understanding of the earliest life on earth and just what that might mean for understanding life on this planet and beyond. From moving life fossilised in mud, to using isotopes to study metabolism and discovering whole new methods of getting food, life continues to astound researchers with its inventiveness.

References:

1. Min Sub Sim, Hideaki Ogata, Wolfgang Lubitz, Jess F. Adkins, Alex L. Sessions, Victoria J. Orphan, Shawn E. McGlynn. Role of APS reductase in biogeochemical sulfur isotope fractionation. Nature Communications, 2019; 10 (1) DOI: 10.1038/s41467-018-07878-4
2. Abderrazak El Albani, M. Gabriela Mangano, Luis A. Buatois, Stefan Bengtson, Armelle Riboulleau, Andrey Bekker, Kurt Konhauser, Timothy Lyons, Claire Rollion-Bard, Olabode Bankole, Stellina Gwenaelle Lekele Baghekema, Alain Meunier, Alain Trentesaux, Arnaud Mazurier, Jeremie Aubineau, Claude Laforest, Claude Fontaine, Philippe Recourt, Ernest Chi Fru, Roberto Macchiarelli, Jean Yves Reynaud, François Gauthier-Lafaye, Donald E. Canfield. Organism motility in an oxygenated shallow-marine environment 2.1 billion years ago. Proceedings of the National Academy of Sciences, 2019; 201815721 DOI: 10.1073/pnas.1815721116
3. Stephanie A. Carr, Sean P. Jungbluth, Emiley A. Eloe-Fadrosh, Ramunas Stepanauskas, Tanja Woyke, Michael S. Rappé, Beth N. Orcutt. Carboxydotrophy potential of uncultivated Hydrothermarchaeota from the subseafloor crustal biosphere. The ISME Journal, 2019; DOI: 10.1038/s41396-019-0352-9

Episode 305 - Reaching space, the darkside of the moon and wet asteroids

It's been a busy week in space news from Virgin Galactic finally reaching space, to wet asteroids and even a mystery in space. We find out about the latest missions to investigate surprisingly damp asteroids by JAXA and NASA. We recap the swirling controversy around a mysterious hole in the Soyuz spacecraft, plus the latest on Chang'e-4's journey to the dark side of the moon.

1. Antczak, J. (n.d.). Virgin Galactic tourism rocket ship reaches space in test. Retrieved from https://phys.org/news/2018-12-virgin-galactic-rocket-ship-space.html
2. Jones, A. (2018, December 12). Chang'e-4 spacecraft enters lunar orbit ahead of first-ever far side landing. Retrieved from https://spacenews.com/change-4-spacecraft-enters-lunar-orbit-ahead-of-first-ever-far-side-landing/
3. Yamaguchi, M. (n.d.). Photos from Japan space rovers show rocky asteroid surface. Retrieved from https://phys.org/news/2018-12-photos-japan-space-rovers-rocky.html
4. Materials provided by University of Arizona. Original written by Erin Morton/OSIRIS-REx and Daniel Stolte. Note: Content may be edited for style and length.

Episode 302 - Ancient empires changing the planet, leaving behind ruins and relics

This week we find out about ancient empires which have changed the face of the planet, changed the climate and left behind trophies of their conquests. From pyramid building termites in Brazil, to large climate changing colonies in Spain and even David vs Goliath battles in Florida with trophies of the dead.

1. Stephen J. Martin, Roy R. Funch, Paul R. Hanson, Eun-Hye Yoo. A vast 4,000-year-old spatial pattern of termite mounds. Current Biology, 2018; 28 (22): R1292 DOI: 10.1016/j.cub.2018.09.061
2. David Martín-Perea, Omid Fesharaki, M. Soledad Domingo, Sara Gamboa, Manuel Hernández Fernández. Messor barbarus ants as soil bioturbators: Implications for granulometry, mineralogical composition and fossil remains extraction in Somosaguas site (Madrid basin, Spain). CATENA, 2019; 172: 664 DOI: 10.1016/j.catena.2018.09.018
3. Adrian A. Smith. Prey specialization and chemical mimicry between Formica archboldi and Odontomachus ants. Insectes Sociaux, 2018; DOI: 10.1007/s00040-018-0675-y

Episode 294 - What is the biggest bird; Island Giants and dwarfs.

What is the biggest bird? Why do some species in some locations end up becoming giants? What makes islands like Madagascar so special and why are so many of the species once found there so very large in size? This week we look at island gigantism and island dwarfism across the world with a focus on the giant Elephant birds of Madagascar.

References:

1. James P. Hansford, Samuel T. Turvey. Unexpected diversity within the extinct elephant birds (Aves: Aepyornithidae) and a new identity for the world's largest bird. Royal Society Open Science, 2018; 5 (9): 181295 DOI: 10.1098/rsos.181295
2. James Hansford, Patricia C. Wright, Armand Rasoamiaramanana, Ventura R. Pérez, Laurie R. Godfrey, David Errickson, Tim Thompson, Samuel T. Turvey. Early Holocene human presence in Madagascar evidenced by exploitation of avian megafauna. Science Advances, 2018; 4 (9): eaat6925 DOI: 10.1126/sciadv.aat6925

Episode 285 - Icey lakes on Mars, a planets worth of dust and unexplained oxygen

We are often tantalized by the prospect of water on Mars, but thanks to a Teenage Satellite we have found lakes of water on Mars, just beneath the surface. Plus we find out where all that martian dust comes from and check in on everyone's favourite Comet, 67-p.

1. R. Orosei, S. E. Lauro, E. Pettinelli, A. Cicchetti, M. Coradini, B. Cosciotti, F. Di Paolo, E. Flamini, E. Mattei, M. Pajola, F. Soldovieri, M. Cartacci, F. Cassenti, A. Frigeri, S. Giuppi, R. Martufi, A. Masdea, G. Mitri, C. Nenna, R. Noschese, M. Restano, R. Seu. Radar evidence of subglacial liquid water on Mars. Science, 2018; eaar7268 DOI: 10.1126/science.aar7268
2. Horner, J. (2018, July 26). Discovered: A huge liquid water lake beneath the southern pole of Mars. Retrieved from http://theconversation.com/discovered-a-huge-liquid-water-lake-beneath-the-southern-pole-of-mars-100523
3. Lujendra Ojha, Kevin Lewis, Suniti Karunatillake, Mariek Schmidt. The Medusae Fossae Formation as the single largest source of dust on Mars. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-05291-5
4. K. L. Heritier, K. Altwegg, J.-J. Berthelier, A. Beth, C. M. Carr, J. De Keyser, A. I. Eriksson, S. A. Fuselier, M. Galand, T. I. Gombosi, P. Henri, F. L. Johansson, H. Nilsson, M. Rubin, C. Simon Wedlund, M. G. G. T. Taylor, E Vigren. On the origin of molecular oxygen in cometary comae. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-04972-5

Episode 283 - Dust storms carrying life, harming life and engulfing a planet

Dust storms can be hazardous, especially when they engulf an entire planet like on Mars. They can also carry pollution across national borders and contaminate wide areas. But Dust Storms may also hold the secret for how life can spread across vast deserts. This week we look at dust storms of this world and out of this world. 

1. Authors: J. A. Rivas Jr., J. E. Mohl, R. S. Van Pelt, M.‐Y. Leung, R. L. Wallace, T. E. Gill, E. J. Walsh. Evidence for regional aeolian transport of freshwater micrometazoans in arid regions. Limnology and Oceanography Letters, 2018; DOI: 10.1002/lol2.10072
2. Tuyet Nam Thi Nguyen, Kuen-Sik Jung, Ji Min Son, Hye-Ok Kwon, Sung-Deuk Choi. Seasonal variation, phase distribution, and source identification of atmospheric polycyclic aromatic hydrocarbons at a semi-rural site in Ulsan, South Korea. Environmental Pollution, 2018; 236: 529 DOI: 10.1016/j.envpol.2018.01.080
3. Penn State. (2018, June 28). Mars dust storm may lead to new weather discoveries. ScienceDaily. Retrieved July 14, 2018 from www.sciencedaily.com/releases/2018/06/180628124412.htm
4. NASA/Goddard Space Flight Center. (2018, June 20). Martian dust storm grows global: Curiosity captures photos of thickening haze. ScienceDaily. Retrieved July 13, 2018 from www.sciencedaily.com/releases/2018/06/180620170956.htm

Episode 281 - Interconnections between animals, ocean currents, climates and ecosystems

This week we look into three stories about how oceans tie our planet together. Our ecosystems are often linked in unusual ways that are not immediately obvious. Ocean currents can tie ecosystems across the world together, impacting migratory species, local environments and ecosystems. Sometimes these impacts are short term, other times they play out over years, decades and centuries. 

References:

1. Carl J. Reddin, Ádám T. Kocsis, Wolfgang Kiessling. Marine invertebrate migrations trace climate change over 450 million years. Global Ecology and Biogeography, 2018; DOI: 10.1111/geb.12732
2. Hector M. Guzman, Catalina G. Gomez, Alex Hearn, Scott A. Eckert. Longest recorded trans-Pacific migration of a whale shark (Rhincodon typus). Marine Biodiversity Records, 2018; 11 (1) DOI: 10.1186/s41200-018-0143-4
3. Jocelyn Champagnon, Jean-Dominique Lebreton, Hugh Drummond, David J. Anderson. Pacific Decadal and El Niño oscillations shape survival of a seabird. Ecology, 2018; 99 (5): 1063 DOI: 10.1002/ecy.2179

Episode 280 - Nanodiamonds, Stardust, Comets and erasing Stars

Astronomy can be quite beautiful at times. From nano-diamonds giving the galaxy a shimmering glow, to stardust leftover from the creation of the solar system hitching a ride on a coment. We also find out about new ways to hunt for exoplanets by erasing stars with filters.

1. Hope A. Ishii, John P. Bradley, Hans A. Bechtel, Donald E. Brownlee, Karen C. Bustillo, James Ciston, Jeffrey N. Cuzzi, Christine Floss, David J. Joswiak. Multiple generations of grain aggregation in different environments preceded solar system body formation. Proceedings of the National Academy of Sciences, 2018; 201720167 DOI: 10.1073/pnas.1720167115
2. J. S. Greaves, A. M. M. Scaife, D. T. Frayer, D. A. Green, B. S. Mason, A. M. S. Smith. Anomalous microwave emission from spinning nanodiamonds around stars. Nature Astronomy, 2018; DOI: 10.1038/s41550-018-0495-z
3. H.J. Hoeijmakers, H. Schwarz, I.A.G. Snellen, R.J. de Kok, M. Bonnefoy, G. Chauvin, A.M. Lagrange, J.H. Girard. Medium-resolution integral-field spectroscopy for high-contrast exoplanet imaging: Molecule maps of the beta Pictoris system with SINFONI. Astronomy & Astrophysics, 2018; DOI: 10.1051/0004-6361/201832902
4. Image Credit: S. Dagnello, NRAO/AUI/NSF

Episode 276 - Hunting for gamma rays

Gamma rays are a mainstay of science fiction, but hunting for these elusive events is a lot easier with the right tools. We find out about two ingenious ways to hunt for gamma rays including flying into a cyclone, using satellites and even a telescope the size of New York.

References:

1. G. S. Bowers, D. M. Smith, N. A. Kelley, G. F. Martinez-McKinney, S. A. Cummer, J. R. Dwyer, S. Heckman, R. H. Holzworth, F. Marks, P. Reasor, J. Gamache, J. Dunion, T. Richards, H. K. Rassoul. A Terrestrial Gamma-Ray Flash inside the Eyewall of Hurricane Patricia. Journal of Geophysical Research: Atmospheres, 2018; DOI: 10.1029/2017JD027771
2. R. U. Abbasi, T. Abu-Zayyad, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, M. Byrne, et al. Gamma-ray Showers Observed at Ground Level in Coincidence With Downward Lightning Leaders. Journal of Geophysical Research: Atmospheres, 2018; DOI: 10.1029/2017JD027931

Episode 273 - Volcanoes across the world - keeping track of potential disasters

With Kilauea erupting, we look at the science of volcanoes and how we can keep better tabs on these rumbling giants of geology. From infra-sound monitoring, to tracking disappearing lava lakes.

Episode 269 - Finding their way through the magnetosphere with quantum mechanics and chemistry

How do animals from bacteria to birds manage to use the Earth's magetnic field to navigate? Do we know how or why? What potential mechanisms are out there and how does quantum mechanics get involved?