A few years ago, astronomers and astrophysicists from around the world got together and decided that Pluto was no longer a planet. It messed up every kid studying science and put those of us who grew up with 9 planets in a quandary.
Instead, Pluto is now a dwarf planet. Not big enough to be a planet but too small to be a moon. Ok. I can understand that. It’s small compared to most of the planets in our solar system, but did they really have to do that? Mercury is small, too. You don’t see anyone trying to say it’s a moon. Evidently, the scientists compared Pluto to a large orbiting body that was close to Pluto, called Eris. In comparing the two, scientists decided that Pluto was smaller. Hence the “dwarf planet” status. Now, 5 years later, they aren’t so sure Pluto is smaller. Technology strikes again.
Here’s what’s next……..a couple of astrophysicists from Australia and Germany want to redefine what a galaxy is.
Ok, you say……but……why???
Because astrophysicists and astronomers have found a galaxy that doesn’t fit the rather vague definition of a galaxy. It’s not the first odd galaxy they’ve found, either, but this is the one that sparked the idea in both of these men. The Oxford English Dictionary defines a galaxy as “millions or billions” of stars but there’s never been a truly official definition. Now, there may just be one, if these guys have their way.
The 2000 finding of a cluster of stars that looks like a cross between a galaxy and a cluster (defined as 100 or more stars) is what started the debate. This large cluster of stars, for lack of a better term, is quite possibly the missing link of how a cluster might turn into a galaxy. Called an ultra-compact dwarf, these “missing links” aren’t very common and are a bit confusing. So, a new definition is needed……so these 2 men say. You can see, in the picture on the left, the ultra-compact dwarfs. They are the ones in the inset pictures and are a bit hard to see.
Again, I can understand that. But……(you knew that was coming!) why can’t they wait for a few more years until more research into ultra-compacts dwarfs is done? Why can’t they wait until other odd-shaped galaxies are studied more in-depth so that a true and fitting definition can be found? Why push for a new definition when there is so much left to explore and study?
As technology advances, knowledge increases and old ideas are tossed out the door (sometimes to be resurrected). Perhaps astronomers and astrophysicists need to learn more about the universe before they change definitions. Space is ever-changing and ever-constant with more oddities and unknown things in it than we can imagine.
I feel sorry for all the kids in school. Like the furor over Pluto, the change of what a galaxy is might just confuse us all.
A little more on Pluto from the History Channel. It’s really good and informative.