Come learn about the New Horizons mission, the team, and the 20+ years it took to get this mission to Pluto. Take a closer look at Pluto, Charon, and the other 4 moons as we dive into the Kuiper Belt, and the extended mission to visit another Kuiper Belt Object.
The event takes place on Friday, Feb 3 and will start in the Multipurpose Classroom Building in room 101 at 7:30p and then move to the top of the Brady Garage at 8:30p, where telescopes will be set up for stargazing (weather permitting).
The weather forecast for this week is not promising, so we’ll cancel the stargazing portion. The lecture will still happen, though.
Showalter and Hamilton analyzed Hubble images of the Pluto system to understand how the moons’ orbits evolve as the result of the gravitational tugs between the moons. The three moons Styx, Nix, and Hydra are very near to and probably in a three-body resonance reminiscent of the Galilean satellites. Computer models of that interaction allowed them to constrain the masses of the moons, somewhere in the range of Mars’ moon Deimos‘ mass.
We would expect that the complex gravitational environment as applied to such elongated moons would likely lead to complex rotation, and indeed, Showalter and Hamilton find that the phase curve for Nix, observed from 2010 to 2012, varies erratically, consistent with a chaotic rotation. Their analysis also shows that Hydra rotates chaotically; probably some of the other moons (except for Charon) as well.
One bit of good news for the New Horizons flyby emerges from all this: the systems’ chaotic dynamics probably keep it clear of rings or additional small moons that would pose hazards for New Horizons. It seems nature has decided the system is complicated enough already.
Attendees at today’s journal club included Jennifer Briggs, Emily Jensen, and Tyler Wade.
Third, Jacob presented a recent paper that extends the Titius-Bode relation to extrasolar systems and predict there are about 2 planets in habitable zones per star in our galaxy. A potentially fascinating result, but unfortunately, the T-B relation is probably just an interesting coincidence for our solar system — it has no theoretical basis, and so there’s no reason to believe it can be generalized to other planetary systems. Nevertheless, the article got a lot of press last week.
Finally, we talked about coding in astronomy, and I wanted to post this resource I just heard about, https://python4astronomers.github.io/. Looks to have a lot of helpful tutorials relevant to astronomy.
Friday’s attendees included Jennifer Briggs, Trent Garrett, Nathan Grigsby, Tanier Jaramillo, Emily Jensen, Liz Kandziolka, and Jacob Sabin.