Saturday, 4 July 2015

Pluto dwarf planet, major star

On the 14th of July 2015 at 11:50 UTC New Horizons will fly by Pluto at an altitude of 7,800 miles. On July 14-15, 1965 Mariner 4 performed the first flyby of a planet, so it will be exactly 50 years. It is 50 years through which I have lived, I'm 5 years younger than the Space age, but 2 years older than planetary research.
Best picture of Pluto 4 July 2015
In that time Pluto's status has changed from Planet to Dwarf Planet, this has caused some upset to some people. In reality, when Pluto was first observed it was the press that decided it was a planet, astronomers new it was different but couldn't spell out why. When other objects similar to Pluto began to be found, starting with the romantically named  (15760) 1992 QB1 in 1992, it became clear that a new classification was needed or there was going to be a vast number of planets, currently there are over 1500 know Trans Neptunian Object and Pluto is more like the larger of these Eris, Makemake and Haumea than it is like the 8 planets.
In mid June the pictures from New Horizons exceeded the resolution of Hubble images, detail is now beginning to show and in 10 days Pluto will be ready for its close up.
When the mission set out it was to complete the set of planetary snapshots, but it appears now that Voyager 2 managed that in 1989. So this mission now represents a much more important milestone, not the end of one phase of discovery, but the start of a new one, a phase that will take many life times to complete, even if new faster than light travel is discovered. The TNOs cover a vast collection of objects including the Kuiper belt, scattered disk, and Oort cloud enough to make sure that we lose interest before getting to them all.
I had a look through the list of predictions of what might be found, I cannot comment on those but did notice one missing and that is a Flux Tube between Pluto & Charon, similar to the Io Flux tube, but far far weaker. I think it is possible only because the solar wind will be so light at that point that even a ghostly tube may exist. For it to exist Pluto must have a magnetic field and Charon an atmosphere. If there is one I want my name on it.
If you are alive on the 14th then you live at the beginning of a greater age of space exploration than any of your dead predecessors. Like the start of all the other ages it will be live on all sorts of media but you should make sure you gather with your friends and family so you can remember where you were when it started.
I know who I was with and where I was when Neil Armstrong stepped onto the Moon and when Giotto passed by Halley's Comet  they are precious memories to me, if not the others present.

New Horizons Web Page.

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