This year at AbSciCon I will be convening a poster session titled “Life in the Anthropocene: The Future of Earth’s Biosphere“. Understanding the future of civilization is one of the goals of astrobiology research, and I welcome a broad range of interdisciplinary perspectives to generate lively discussion at this session.

Life in the Anthropocene: The Future of Earth’s Biosphere

Organizer: Jacob Haqq-Misra (Blue Marble Space Institute of Science)

Summary: The distant future of Earth’s biosphere will be shaped by the balance among factors such as orbital variations in solar insolation, cycles in glacial coverage, the carbonate-silicate cycle, and the resonating effects of anthropogenic climate change. Even longer geologic timescales will force the climate to adapt to a steadily brightening sun by drawing down atmospheric carbon dioxide until habitable conditions no longer remain. This poster session invites contributions that consider potential threats or challenges to the future of civilization, life, and climate from factors that will affect the Earth system over the next 100,000 to million years or longer.

http://www.hou.usra.edu/meetings/abscicon2015/program/topics/

Feel free to contact me if you have any questions regarding the suitability of your abstract for this session, and please share this session information with any of your interested colleagues.

December Shows

We’re trying out a new venue in Altoona this month with two shows at The Empire music club. With space large enough for the band and a full sound system, we’re looking forward to seeing our friends in Altoona again.

Dec 6 – Mysterytrain @ The Empire (Altoona, PA)

Dec 31 – Mysterytrain @ The Empire (Altoona, PA)

We’ll also be at The Empire for New Year’s Eve to bring in the year with style. Looking forward to finally having the full band reunited once again in 2015!

Small red stars, known by astronomers as “M-dwarfs”, are the most abundant type of star in the sky and are also the most long-lived of all stars. This means there are plenty nearby of M-dwarfs to search for possible habitable planets, and many current and planned exoplanet surveys emphasize the search for potential worlds orbiting within the habitable zone of these low-mass stars. Astrobiologists often use the term “habitability” to indicate a planet’s ability to sustain liquid water on its surface, thereby providing conditions where life might be able to develop and thrive. The corresponding “habitable zone” describes the range of orbital distances that can support these clement conditions and not lose the water to a rapid runaway greenhouse (from too close an orbit) or a cool condensing atmosphere (from too far an orbit).

The problem with planets orbiting M-dwarfs is that they are prone to fall into “synchronous rotation” so that one side of the planet always faces the star, while the other side remains in perpetual darkness. Synchronous rotation can occur as a result of tidal forces from gravitational interactions between two orbiting bodies (Earth’s moon is an example of an object in synchronous rotation, so that we only ever see one side from the ground). For a planet orbiting an M-dwarf, the “sub-stellar point” beneath a constant stream of starlight is ceaselessly warmed, while the opposing “anti-stellar point” receives no starlight at all and resides in total darkness. One potential problem is that the atmosphere may condense into large ice caps on the frigid night side of these planets, which could result in total atmosphere collapse and the loss of habitable conditions.

Fortunately, the large-scale motions of the atmosphere help to redistribute this energy and, in many studies with climate models, can help avoid this atmospheric freeze-out. In a paper published in the Monthly Notices of the Royal Astronomical Society, my co-author and I use a three-dimensional computer climate model to examine the role of geothermal heating on planets orbiting M-dwarfs. Geothermal heating is another consequence of tidal forces from a close orbit, and this additional surface warming can help to amplify the asymmetric distribution of energy transport toward the night side of the planet. This can help to induce the melting of ice near the anti-stellar point and create additional habitable area surrounding the night-time hemisphere.

We also examine the large-scale dynamical circulations on these synchronous rotating planets in comparison to the general circulation patterns on Earth. We demonstrate that the direction of of the meridional (i.e. north-south) circulation changes directions from one side of the sub-stellar point to the other. That is, a global average of the meridional circulation provides an incomplete picture of the large-scale dynamics because the eastern and western hemispheres each show strong motion but in opposite directions that cancel when summed together. Additionally, we examine the presence of a cross-polar circulation that transports energy and mass from the sub-stellar to anti-stellar point across the northern and southern poles. This also contributes toward maintaining climate stability and avoiding atmospheric freeze-out with a circulation pattern atypical of those observed on Earth.

Our study emphasizes the need for careful analysis when considering how the atmospheric dynamics of a synchronously rotating terrestrial planet may differ from our own. The study of Earth-like exoplanets must begin with analogies to observations on Earth, and studies like ours help to apply Earth system models toward more general planetary system. As research into planetary habitability continues, through theory as well as observations, we will indeed continue to observe how even basic physical principles can manifest in very different ways on these alien worlds.

September/October Shows

Thanks to everyone who came out to see us at Shaw’s this month! It’s always a fun time jamming out in Altoona.

Sep 6 – Mysterytrain @ On the Rise 3 (Elysburg, PA)

Sep 13 – Mysterytrain @ Shaw’s Bar (Altoona, PA)

Sep 19 to 21 – Mysterytrain @ 6th Anniversary Jam (Millmont, PA)

Oct 11 – Mysterytrain @ Jackalope Halloween Festival (Northumberland, PA)

Oct 25 – Mysterytrain @ Argilla Brewing Company (Newark, DE)

Looking forward to the 6th Anniversary Jam as summer winds down. The weather is looking clear, and we’ve got some new bands on the lineup, too. Should be a good turnout and a great time this weekend at Sunsational Family Campground!

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