Observing with Street Lights

Observing with Street Lights
Dark sky sites not always necessary to see the Milky Way (This image was taken ouside of a B&B in Julian, CA)

Wednesday, October 19, 2016

Resident Astronomer at the AAS/DPS meeting in Pasadena; Sad faces during live Exomars landing broadcast; Ceres asteroid and bright spots; Pluto losing its atmosphere?

Greetings from Palmia Observatory

Well, I'm still offsite at the AAS/DPS meeting in Pasadena.
Started yesterday's meetings with a live broadcast from ESA covering the landing of Exomars lander, Schiaparelli.  Well, there were a lot of sad faces when the lander communication was lost just about a minute before touchdown.  Yes, we know it is hard to get to Mars and things don't always go right.  The latest news from ESA says that the premature ejection of the heat shield and parachute were found in the telemetry.  We will have to wait for
more news, maybe even the ESA orbiter, which successfully went into orbit can find the lander on the surface.

Live feed from ESA ExoMars control room -- Sad faces for loss of signal from Schiaparelli lander, 8/19/16


I spent many hours deciding which of dozens of sessions to attend, and decided to rotate around and get sort of a smidgen of many different topics.  The presentations were often laden with technical data that mostly appealed to experts, but I did get a sense as to what the major issues were all about and decided to mostly attend sessions on asteroids and comets.  There were several presentations about the Dawn mission to Avesta and Ceres.  Hey, I've taken a picture of Ceres!  Well, my picture, composed of just a couple of dozen pixels left a lot to be desired.  Dawn's photos now clearly show the white bright spots in the Occator crater.  The planet scientists identified the spots as deposits of mostly sodium carbonates, that would have needed some water to have formed.  Pretty neat.  The water does not seem to be areound now.

One interesting little factoid came up during some of the Pluto and New Horizons sessions and that was that for a number of years ther has been concern that the atmosphere of Pluto would collapse before a mission to Pluto could get launched.  It turns out that Pluto's atmosphere has not collapsed as fast as some predictions assumed.  Why would it collapse?  Well, remember that Pluto is in an eccentric orbit of 248 years and just past the closed approach to the sun in 1989.  In the year 2114, Pluto will be time furthest away from the sun, that is 49 AU, compared to 29 AU in 1989.  Now as Pluto continues to move away from the Sun and the solar radiation on its surface continues to decrease, some calculations showed that its atmospheric pressure, as meager as it already is, would decrease even further.  There was some discussion about how much thermal inertia was stored in the planet and atmosphere, which would have maintained the pressure a bit longer as the planet started moving further away from the sun.  Keep in mine too that since Pluto was discovered there has not been enough elapsed time for it to make even one turn around the sun.  Luckily, the New Horizons arrived at opportune time to great scientific success.

Until next time,

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