Robert Inventor

Everyone has started to call this new proposed planet X: "Planet nine" as in the original announcement. Even Wikipedia has titled its article on it "Planet Nine". But it's a poor name for a planet if you think about it. Why not just call it "Planet X"? Or find some new name, like Nemesis and Tyche as was done for previous planet X candidates.  None of the previous candidates for Planet X were called Planet + some number, and with good reason. There is no way that we can know it will be planet 9. 

As someone who is keen on astronomy, I am of course keen on the Thirty Meter telescope myself. And I've heard those arguments of the astronomers, about how it is an ideal site for astronomy, about the value of the astronomy that can be done with this telescope and so on. But I've also heard the other side too.There are many telescopes on the summit already, so it's not like they are saying not to build telescopes at all up there.SIZE OF THE PROPOSED TELESCOPEWhat you might not realize at first is quite how huge it is - it's difficult to get a sense of scale from the images:It's higher than the Niagara falls.

Just a short post, since I do articles here from time to time to reassure those who worry about collisions with Earth for every new discovery. This new planet X is not even proved to exist yet. But if it is - it orbits way beyond Neptune. It is no more of a threat to us than Neptune was when it was discovered in the nineteenth century. Rather it's fun and exiting, and we could learn new things from it if it exists.

Actually though most of the stories say it is the first flower to bloom in space, and Scott Kelly tweeted it as such, it turns out that there have been several flowers grown in space before, most recently in 2012, but the first such was way back in 1982. It does seem to be the first Zinnia to flower in space.Here is Scott Kelly's tweet

Sometimes it's quite hard to tell if an article is sensible, especially if you don't know much science. But there is one thing anyone can do, quite easily - and that is to check sources.  I'll do this for the "Nibiru" nonsense stories so you can see how this works. The most unreliable and nonsense stories, as well as getting the science wrong, also tend to get their sources wrong as well, so this can be a good test to check for unreliable news stories.

Discussions of the ethics of terraforming often touch on  rights of planets or extraterrestrial lifeforms, or near term utilitarian values. But what about our responsibilities to terraformed worlds, and their long term future? I suggest that we are nowhere near mature enough as a civilization to be responsible parents to a newly terraformed world with a gestation period of millennia and an "adult life" of hundreds of millions of years.

Let's declare Pluto as a dwarf or sub dwarf planet AND a planet! This is about the vexed question of whether Pluto is a planet or not. Yes the International Astronomical Union "settled the question" but I'm not sure their decision is one that will work all the way into the future, for instance if we find Earth or Neptune sized objects beyond Pluto. And it also stretches language in an awkward way to say that Pluto is a dwarf planet but not a planet - and the English word "dwarf" seems to have little to do with the concept of clearing your neighbourhood.

I got many comments on last week's Nibiru article from some very scared people. They needed a lot of reassuring that it was indeed a hoax and not real, and brought up many topics to discuss such as lens flares, hoaxes, double sun videos, rare sun mirages, and the status of the astronomical search for various versions of planet X. Why are astronomers so sure that Nibiru is nonsense?

I first wrote this after a recent particularly silly story about Nibiru, published in the Daily Telegraph: The end of the world now predicted for December say doomsday groups: "Terrifying stuff. Apparently, the planet due to collide with us is often visible, you may have seen it already. If you spot a blob next to the sun when you take a photograph, it could be the deadly planet, not a reflection."

Science fiction stories often suggest that ETs, and our future selves also, would be expansionist, colonizing the galaxy, taking over worlds, and so forth. It's natural enough, because we are expansionist ourselves. But it's actually quite easy to see that ETs simply can't have expanding populations, at least not for very long. Not if they are anything like us. It's a simple calculation which I covered before. If their doubling time is once a century, say (for  ease of calculation) - then in a thousand years, their population multiples by a little over a thousand (two to the power ten). So after two thousand years it has multiplied by a million, by a billion after three thousand years and so on.

Sorry, I accidentally made two copies of this article with different titles. And both have comments, so not sure what to do. Unless you want to read the comments here, please visit the newer copy, Why ETs Won't Need to Colonize or Expand.

Can an astronaut throw a ball to the Earth? The answer is Yes, and No. Depends what you mean by hitting the Earth. First, if you throw a ball towards the Earth - yes it's traveling that way when you throw it. So, it is natural to think that no matter how slow it is, it would get there eventually. However, we aren't used to throwing things in orbit, and our intuitions can often lead us astray.