Yesterday I went to a local astronomy club (NOVAC) to unleash the geek in me. I am really excited about it and I will have to get a membership to it to be able to sky observe with all the amateur to pro astronomers.
Before I get off topic before I even start, the main feature of the night was this particular mission. I actually hadnt heard about it but it launched in 2006 and will arrive at Pluto in 2015 (unknown date, didnt say). A Professor at George Mason University is a part of and the co-leader of the team that developed and launched the mission.
Throughout the presentation he was describing what they predict to see. First some details though on the flyby.
- It will take the first clear photos of the surface
- It will be able to detect everything about the dwarf planet from the magnetic field (indirectly), but more importantly the atmosphere and what it is made of.
- It will also look at Charon and the 2 other small recently discovered moons.
- Pluto at this time will be inside the orbit of Neptune and close to the sun so that its warmest. If closets is 30.0 AU, it will be at 30.6 AU or something like that. More details below.
- Its a flyby mission as in it will not be able to circle Pluto and Charon. Instead it will race beside the them as it orbits taking as long as possible.
- There's only one chance. But after the flyby they will fly it out into the Keiper Belt looking for other Pluto sized objects floating about.
Now, what he was saying is that Pluto does in fact have an atmosphere. They have discovered this by looking at the spectra from when Pluto passes in front of far away stars and their light. It looks to be made up of mostly hydrocarbons, methane, and nitrogen. It also happens to be very very thick and stretch 1000's of km out from the surface rather than maybe 100km as an onion skin atmosphere on Earth as he said.
One of the ways he described how the small planet gets its atmosphere is from the ice. The ice is thick and has all of the gases frozen into it when its furthest from the sun. As it gets closer, the Sun's rays warm the ice very slowly from maybe only 40 Kelvin to about 100 Kelvin (estimated). Still cold, its warm enough to let the ice start to sublime into gas, creating the atmosphere that is seen. They are also predicting it to have geysers judging from the hazy and drastically changing colored pictures taken from Hubble.
The reason why it is so thick is not because of gravity but because of the thermal energy holding it together. Id have to double check on those details. Over time, most of it probly escapes and the rest is frozen again as it is thrown off further away from the Sun. Also even more compelling is that they think that Charon may be pulling Pluto's atmosphere to its own surface like a Neutron star pulling material from a normal star in a binary system, although not as spectacular obviously, but it will be the only planet that does this in our solar system.
Anyways, I think this project has tons and tons of potential. I was super excited hearing all of this and it makes me ask more questions. I asked if he could expect any weather or lightning. He said probly no rain or clouds but lightning is a very good possibility. I will try and post a link of a good article if I can get one. Ill have ask.
What do you think?