Walkabout the Galaxy

Ten years after the development of a dramatic new picture of the early history of the solar system, dubbed the Nice model (it was created at the Observatory in Nice, France), it has undergone several tweaks and modifications. The model posits a reshuffling of the big planets that led to a number of our current solar system's notable features, such as the late heavy bombardment, the distribution of orbits of asteroids and comets, and Keeping Up With the Kardashians. On this episode of WtG, we welcome Akbar Whizin to discuss new research that reshuffles the Nice reshuffling, as well the new Star Trek TV show and the charming nature of baseball statistics.

Jim Cooney joins Josh and Addie to talk about the origin of galaxies and the observation of a galaxy from when the universe was but a teeny weeny baby of a universe, less than 1/12th its current size. Also, Scott Kelly is back on terra firma and has to deal with gravity. Hear all about redshifts, the big bang, and hyposprays on this episode of Walkabout the Galaxy.

A long time ago in a galaxy far, far away, two big black holes (no jokes, please) collided with each other releasing a ginormous amount of energy that has propagated across the universe as the tiniest stretching and jiggling of space itself. Jim Cooney joins Josh and Addie to talk about the first direct detection of the waving of space-time (in other words, gravitational waves).

Not content with being the self-proclaimed "Pluto Killer", CalTech professor Mike Brown has now co-authored a paper hypothesizing the existence of, in his own words, "the most planet-y of planets" or "Planet 9", in the far outer reaches of our solar system. We get it: you hate Pluto! But personal planetary battles aside, this is an interesting bit of dynamical detective work in which lead author Konstantin Batygin and Brown argue that a roughly Neptune-sized planet several hundred times further from the Sun than the Earth is needed to explain the peculiar configuration of a dozen or so objects in the Kuiper Belt. Jim Cooney joins Josh and Addie to talk about Planet 9. If it's the most planet-y of planets, let's come up with a new name for whatever the Earth is.

So what do floods in the southwest have to do with the price of anchovies? Join Josh, and Julie Brisset and find out in this episode of Walkabout from our guest Professor Dan Britt. But first: Star Wars. Spoilers abound.

Join us for a discussion with Dr. Alan Stern, Principal Investigator of the New Horizons mission to Pluto, and hear about the mission and its discoveries from the man who made it happen. New Horizons is headed towards its next target, a smaller object in the Kuiper Belt, the region of space beyond Neptune that was also, as it turns out, the birthplace of comet 67/P Churyomov-Gerasimenko. Yep, that's the comet that the ESA mission Rosetta is studying, and none other than Alan Stern is the P.I. of the ultraviolet spectrometer on that mission. It's all about the Kuiper Belt and missions to explore it with Alan Stern on this episode of Walkabout the Galaxy.

Why is there no air on Mars? NASA's MAVEN mission has supplied some details on how our neighbor lost what was likely a robust atmosphere comparable to Earth's. Spoiler alert: size does matter. Mars' diminutive scale poses a number of problems for holding onto the atmosphere. MAVEN has now witnessed erosion of the atmosphere due to the solar wind. Hear about Mars and more on this episode of Walkabout the Galaxy.