Random Developments

The whole Pluto story has been all over the blogosphere and the regular media, so I didn’t talk about it much. In the end, I liked that the IAU reached a decision (disputed as it may be), even though I actually preferred the option that was announced the week before (12 planets, not 8).

The Australian “Cosmos” magazine has a good editorial online about why Pluto had to go; and, to be honest, I do hope this subject dies quickly and that people get it over with.

In other news, astronomy-related posts will now be found here; this blog returns to its regular programming.

One other proposal that has surfaced for the definition of a planet is to accept anything that has an intrinsic magnitude (brightness) that is equal than or larger than Pluto’s. This would keep Pluto as a planet, and would also include 2003UB₃₁₃, a.k.a. Xena, which would then (I suspect) be named in accordance with the naming rules for planets (names of Greek gods). Nothing else would make the cut, though — Sedna, Ceres etc. would not be considered planets.

The IAU conference happens over the next two weeks, and a blog with information on everything that happens (not only about Pluto, of course) is at http://astronomy2006.blogspot.com/.

NPR reports that a IAU panel has unanimously recommended that Pluto (in the photo with its larger moon, Charon) keep its status as a planet, and it is possible that we may end up with several objects being recognised as new “dwarf planets”.

I mentioned a while ago that the IAU was going to decide on an unambiguous definition for the word “planet”, and that it was likely that this would change the number of planets in our solar system. The decision has not yet been reached; this should happen later this month. However, several members of the aforementioned panel suggest that Pluto will join a new group called “dwarf planets” (we already have “terrestrial planets” and “giant gas planets”), which might include any body that orbits the Sun and that is large enough that its own gravity makes it spherical (or nearly so); this would include anything larger than some 700km across.

This definition would include not only Pluto and Xena (a.k.a. 2006UB₃₁₃), but also other smaller bodies such as Ceres (an asteroid between Mars and Jupiter). This would take the number of known planets to something like 13 or 14, but it is unsure whether this will be approved.

The IAU general assembly opens tomorrow, 12 August, in Prague.

Great article: Faith Based Programming.

I think I know some people who practice it.