Out of the Silent Planet

In this episode we talk to Audrey Martin - a doctoral candidate at Northern Arizona University using thermal infrared spectroscopy to study Jupiter's Trojan Asteroids. Join us in a conversation about graduate school, Audrey's doctoral research, Jupiter's Trojans, the upcoming Lucy mission, and the James Webb Space Telescope.

In this episode we explore the ethics of asteroid mining, using a white paper led by Andy Rivkin of JHU/APL. It's unlikely that asteroid mining will have zero consequences, and without a well-defined legal infrastructure, asteroid mining could be the next wild west where the rich get richer. Join us in a discussion about what we should be considering before extracting precious metals from some of the most ancient and irreplacable rocks in the solar system. 

In this episode we discuss Anne Hofmeister's idea that the motion of Earth's tectonic plates is caused by the rotation of the Earth. This idea is contrary to that held by most geologist that mantle convection is ultimately responsible for plate motion. 

In this episode we explore the possibility that a ninth planet lurks along the outskirts of our solar system. Could it be a Small Neptune? A Super Earth? Or just Fake News. We discuss some of the history of successful and failed hypothesized planets, the structure of the outer solar system, likely properties of a putative planet nine, how it could be detected, and how it might have formed. Timestamps: 00:32 - Welcome 05:35 - Basics of Planet 9 and history of planet detection 43:29 - Where could P9 be, what is it like, and why do we think it could exist?

In this episode we discuss planetary magma oceans in the solar system with a focus on the Moon - the first body for which a magma ocean was proposed. Timestamps: 00:32 - Welcome 02:50 - Moon rocks (Wood et al, 1970) 52:22 - Magma oceans (Elkins-Tanton, 2012)

On our first mission-focused episode, we tackle the joint NASA/ESA Cassini-Huygens mission that studied the Saturn system from 2004 to 2017. Over those 13 years (about one half of a Saturn year), the Cassini orbiter collected a vast dataset for studying Saturn's iconic rings, enigmatic icy moons, and the gas giant itself, while the Huygens lander made a brief visit to the surface of the hazy moon Titan. We discuss the basics of the Saturn system, the Cassini-Huygens mission, and its major findings, but first — a brief chat on China's successful landing of a rover on Mars. 00:32 - China is on Mars! 13:00 - Basics of the Saturnian system and pre-Cassini history,  34:22 - Cassini mission architecture and findings.  Cassini links:  Overview of the Cassini-Huygens mission (Matson et al., 2002),  Overview of Huygens landing on Titan (Owen, 2005),  Saturn's icy moons before and after Cassini (Dougherty & Spilker, 2018),  Overview of Cassini-Huygens results (Spilker, 2019), More detailed review of Saturn findings (Ingersoll, 2020).

On the surface of Mars we see geologic evidence of past liquid water activity. However, climate models of its past mostly point to a cold and icy Mars, in part because our sun used to be dimmer. So was ancient Mars warm and wet or cold and dry? On today's episode, we discuss why it was probably a bit of both, after a quick laugh about a recent effort to simulate an international response (or lack thereof) to an incoming asteroid. 00:00:32 - Welcome & the world isn't ready to stop asteroids, 00:07:33 - Rainfall on a warm & wet early Mars (Craddock & Howard, 2002),  01:15:54 - Updated constraints on early Mars climate (Kite, 2019), 02:02:18 - New model of a mostly cold early Mars (Wordsworth et al., 2021) and summary (Mangold, 2021).

In this episode we discuss the issue of Planetary Protection, that is, how to keep terrestrial microorganisms from hitching a ride and potentially contaminating other worlds in our solar system. Specifically, we discuss the basics of international planetary protection policy, why we might be a little too overprotective of Mars, and how the Europa Clipper team is calculating the risk of contamination for their mission. Plus, the lil' helicopter Ingenuity takes flight on Mars and SpaceX has another smooth delivery of NASA astronauts to the ISS!  Timestamps: 00:32 - Welcome, Ingenuity flight, and SpaceX Crew-2,  16:15 - Planetary Protection in the New Space Era (Cheney et al., 2020),  41:14 - The astrobiological exploration of Mars (Fairén et al., 2019),  1:16:27 - Europa Clipper planetary protection probabilistic risk assessment (McCoy et al., 2021).

In this Episode of OoTSP, Michael and Tony discuss all things NASA-funded space science missions. How do the science questions that guide missions get formulated? How much money do missions cost? Who decides which missions fly and which were a waste of a decade for those unfortunate unselected Principal Investigators? Timestamps: 00:32 - Welcome 08:21 - Introduction to NASA structure and missions 34:50 - Main Segment: MASWG Document Links: Visions and Voyages - Decadal Survey for 2013 - 2022 The Decadal Survey for 2023 - 2032 NASA Solar System Exploration Programs NASA Organization Structure NASA Planetary Science Division NASA Science Mission Directorate NASA Science Missions

On today's episode, we discuss interesting presentations from the 2021 Lunar and Planetary Science Conference. New missions, new discoveries, and upcoming events are all on the menu. With this year's conference being virtual, we also discuss some of the pros and (mostly) cons of attending conferences online. 00:00:32 - Welcome - an Icelandic eruption! 00:04:10 - What is the Lunar and Planetary Science Conference? 00:07:43 - Recent updates from NASA and upcoming mission plans 00:45:30 - The legacy of Arecibo (Campbell) 00:59:15 - Titan talks (Schurmeier; Lapôtre) 01:14:20 - ‘Oumuamua (Jackson) 01:29:15 - Variations on Mars water (Citron; Scheller; Lauro; Lalich) 01:46:20 - Stylish presentations (Viviano; Byrne; Stähler)  01:54:04 - Closing thoughts on virtual conferences

Every so often the humungo dipole magnet that produces Earth's magnetic field reverses polarity - that means magnetic north becomes magnetic south and vice versa. In this episode we explore the potential effects reversals like these have on us biological beings dwelling on the surface and on the Earth's climate, and whether Earth is “due” for another reversal in the near future. We also talk about whether magnetic fields protect a planet against atmospheric escape with implications for terraforming Mars, and the potential for continuity in the Artemis Program with the changing presidential administration. 00:32 - Welcome and the future of the Artemis Program? 07:13 - Does our magnetic field protect us from harmful high-energy particles and how does the magnetic field work? 39:16 - Was the last magnetic field reversal a catalyst for cave art and extinctions? Are we due for another reversal soon?  45:30 - Michael mentions a correlation between exposure to Galactic Cosmic Rays (GCRs) and skin cancer. This isn't necessarily true. Skin cancer is predominantly caused by sun exposure (UV and higher energy light). Although, there is a correlation between exposure to GCRs and cancer in all organs. Links: The continuity of the Artemis Program through the administration change Magnetic fields don't protect atmospheres (Gunell et al., 2018) A global environmental crisis 42,000 years ago (Coop et al., 2021) https://astrobites.org/2020/11/17/radiogenic-heat-hurts-dynamos/

Was humanity hit with a comet 12,900 years ago? Will we be hit again in a few decades? In today's episode, we discuss the highly debated argument that a comet struck the Earth in our recent past, causing the global cooling observed during the period known as the Younger Dryas (12,900 to 11,700 years ago). We also discuss the near-Earth asteroid Apophis and its upcoming close encounters with our world that, although unlikely to impact, could enable some opportunistic science. And of course, we give a shoutout to the Perseverance Rover, which just executed an impressive landing on Mars! 00:32 - Welcome and a new rover on Mars Watch the Perseverance Rover land on Mars 07:13 - Asteroid Apophis is coming! 39:16 - Younger Dryas Impact Hypothesis Links: The Case for Apophis Apophis T-9 Years meeting Apophis composition on SoundCloud The Younger Dryas impact hypothesis: a critical review (van Hoesel et al., 2014)

In this episode we discuss the possibility that the Moon drags the Earth's lithosphere westward, ultimately causing plate tectonics, as well as Alfred Wegener's first proposition of continental drift way back in 1912, and the possibility of taking a $GME rocket to Pluto… 00:32 - Welcome: gamestonk and Mercury moves, 08:38 - Some background on Wegener and continental drift (Demhardt, 2006), 58:18 - Western migration of plates seen in asymmetric ocean ridges (Chalot-Prat et al., 2017). More links: Space geodesy validation of the global lithospheric flow (Crespi et al., 2007), Tidal modulation of plate motions (Zaccagnino, Vespe, and Doglioni, 2020), Brexit 1.0, Looking for plate tectonics in the composition of stars (Jura et al., 2014)

In this episode we discuss recently published papers about possible fluvial erosion on Venus and possible recent volcanic activity on Mars, as well as a recent Nature paper that caused a buzz on Twitter for its conclusions that female mentors are bad for the careers of their female protégées. 00:32 - Welcome & discussion on mentorships and gender 17:29 - Evidence of fluvial erosion on Venus 36:35 - Evidence of recent volcanism on Mars 1:43:08 - bonus content just for you Originally recorded November 25, 2020.

In this episode we talk about a 2016 Nature paper that explores potential biosignatures on Mars, and a 2018 paper about "Cosmic Panspermia". 0:30 - intro, RIP Alex Trebek 5:37 - Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile 47:11 - Cause of Cambrian Explosion: Terrestrial or Cosmic? 1:59:58 - continued discussion on cosmic panspermia

In this episode we talk about some of the issues astronomers have with planned satellite mega-constellations like Starlink and the increasingly dangerous problem of Earth's orbital garbage heap, and pontificate on the US presidential election. 0:30 - intro discussion on US politics 25:51 - space junk 57:04 - SpaceX Starlink and its effects on astronomy Links: Why Nature supports Joe Biden for US president The Elusive Peril of Space Junk Concerns about ground based astronomical observations: a step to safeguard the astronomical sky

In this episode we talk about how to avoid confirmation bias through use of multiple working hypotheses, the recent winners of the Nobel Prizes in Physics & Chemistry, and also some of the fantastic Ig Nobel Prize winners. Note: Tony's audio is a little sketchy at first, but improves after about 15 min, so keep listening! We're still getting the hang of this... 00:30 - the 2020 Nobel Prizes in Physics & Chemistry 30:12 - the 2020 Ig Nobel Prizes 42:30 - The Method of Multiple Working Hypotheses 1:45:22 - The show after the show (igNobel encore) Links The 2020 Nobel Prize in Physics press release The 2020 Nobel Prize in Chemistry press release The 2020 Ig Nobel Prize Winners The Method of Multiple Working hypotheses

In this episode we talk about the role of analogical reasoning in creating scientific hypotheses, Meteor Crater in Arizona, and a recent paper in Nature Astronomy that claims subglacial lakes exist beneath the martian south pole(!). 00:39 - Welcome and Intro 04:48 - Subglacial lakes on Mars 36:35 - Origin of Hypotheses

Disclaimer: This episode is a little rough around the edges as we work out some kinks in our first ever recording. Hence, let's call it the Pilot. Give it a listen, but hey, I warned you! In this episode we talk about the recent detection of phosphine in the venusian atmosphere and discuss a review paper on the limits of life in our solar system and beyond. 00:30 – Welcome and Intro. 01:50 – Phosphine on Venus = life on Venus? 30:09 – Limits of Life in Planetary Systems