Saturday, October 16, 2010

DPS Notebook, Odds and Ends

Still emptying the DPS journal folks, one more to go after this one, but that one won't be about DPS per se, just general musings on the profession, conferences, etc. (something I wrote at 4AM on the plane home, so I've yet to decide whether to throw it up).

The first thing to mention is that I was lucky enough to get a total of six interviews with early career folks at the DPS and I feel they went rather well. After speaking with my colleagues at "Live at York U" over on Astronomy.fm, we have come to a decision regarding the schedule. Things kick off with a little introduction from me on October 18th, including some clips from talks by Ray Arvidson, Bob Pappalardo, Steve Squyres and Jim Green, then we get into the meat of things:

October 25th - Dr. Jason Barnes (Idaho)
November 1st - Dr. Catherine Neish (Johns Hopkins/NASA-APL)
November 8th - Dr. David Minton (SwRI/Purdue)
November 15th - Dr. Britany Schmidt (Texas)
November 22nd - Dr. David Choi (Arizona)
November 29th - Dr. Jonathan Fortney (Santa Cruz)

Note that all interviews will run over on Astronomy.fm at 8PM Eastern, 5PM Pacific. I believe that we will be shifting with the clocks when that happens, so for listeners in Arizona, note that time change. I am also happy to report that all the interviews will run in complete form, and have only been slightly cut. So look for 20-30 mins for the interviews.

I'm planning on doing a little blurb about each of the subjects on the day their interview airs. But I will reveal this much now: in addition to planetary science we all share a connection to the Lunar and Planetary Laboratory at the University of Arizona. Some of us are still there (Choi) and most of us got our PhD's there (exception: Schmidt [UCLA]). In part I picked these people because I was familiar with them, even if I don't know them that well personally. But it is a testament to the program at LPL that I didn't have to look outside to find a wide range of expertise and planetary targets for study. We will be spanning the entire solar system both in time from its formation to the present day, and from the Earth, through the Asteroids, Jupiter, Europa, Saturn, Titan, the Ice Giants, the Kuiper belt and on to Extrasolar Planetary Systems.

Are you a Planetary Scientists and would like to be the subject of a future interview? Drop me a line in the comments! If you're located in the Greater Toronto Area or will be at next March's LPSC, we can arrange something taped, otherwise we can do a live interview. Either way we'd love to hear from you!

Other interesting tidbits (based on my #DPS2010 posts):

(1) Mars just keeps getting more warm and wet in the past - we've found exposures of the missing carbonates exposed by impact craters all over the place. The absence of carbonates was a major mystery for a long time. However, it seems that much in the same way that most of the water-altered minerals at Gusev were buried by later deposits, the carbonates are not absent, merely covered up! I was less impressed by the atmospheric modelling teams who used today's martian terrain and obliquity to describe the movement of volatiles 4 billion years in the past. While it's true that we don't know what that Mars would have looked like, it seems clear that Tharsis, at least, would not have existed. Since, in the current day, Tharsis is a major obstacle for a moving air mass and causes a great deal of atmospheric condensation through orographic cloud formation it should not be present in past models. Still, the authors did point out that it is difficult to support liquid on Mars with the faint young sun, even if you assume a very thick 5 Bar CO2 atmosphere.

(2) A consensus is emerging over lunar swirls - as someone who has done some geomorphology, I'm a sucker for an interestingly shaped surface feature. The lunar swirls have been a mystery for a long time since they were first seen in the 1960s. In an impressive series of talks in the lunar session, observations made by LRO placed brick after brick in the foundation that these are features in which variations frozen into mare lavas have been emphasized by differential space weathering. The anomalous magnetization of these features show that they deflect the solar wind. Thus, in addition to their differing magnetization they show differing albedos and a lack of solar-H implantation (so no hydrated water). However, Radar backscatter shows no difference in roughness, implying that the swirls are only skin deep (less than 15cm)!

(3) The disappearing exoplanets announcement - a great deal of excitement surrounded a talk called "Title Embargoed." After all, if we couldn't know the title ahead of time, it must have been a pretty big discovery! However, through the magic of delayed peer review, the presenters took to the stage only to announce that Nature would not permit them to speak about the work. Speculation as to what was to be reported was rampant, as were thoughts as to why the reviewers might be drawing out the process. In this highly competitive field, it could be that the reviewers are stalling until they can replicate the result. Or it could be that the discovery is itself uncertain and the authors are having difficulty satisfying the reviewers that their discovery is genuine, above the error bounds of their measurement. For an example, just take a look at the discovery (or not) of an earth-sized planet just this past week.

(4) Titan surface geology outpaces our wildest hopes - data from Radar and VIMS were presented in which wave height in the Titanian lakes was constrained both from specular glinting and backscatter. As well, the controversial proposition that the equatorial "coffee ground" sand dunes show interspersed liquid hydrocarbon seepage was debated.

(5) Faster computers make dynamical calculations better - some of the major problems in solar system formation are beginning to sort themselves out, in particular the long-standing puzzle of why Mars is so small. It seems that the solution may be that as the Giant Planets migrated inward then outward, they created a sharp edge to the disc of planetessimals which formed the inner planets. As well, the outward migration would have scattered a great deal of icy material in past the solar system's snow line, enhancing the amount of water delivered to the terrestrial planets. This is troubling from an astrobiological point of view, since to make this situation work you need two large gas giants which form early and in just the right places and then evolve until they hit a resonance with one another many millions of years down the road. How common is that type of formation? At the very least it adds another term to the drake equation.

1 comment:

  1. wow lots of stuff here!

    I really like your title 'conversations from DPS' and the logo that goes with it...would you be interested in generating a logo for live at yorku? we could use one.

    ReplyDelete