Editor’s Note: Time to rewrite the textbooks
Editor-in-chief Elizabeth Finkel discusses the latest issue of Cosmos Magazine in her editor's note.
Welcome to the first quarterly issue of Cosmos magazine. I hope you’re sitting down, because there’s a lot of head-spinning stuff in here. So many things you thought you knew that just ain’t so.
Here are a few samplers.
At high school you probably learnt the Solar System had nine planets. Eleven years ago, with the banishment of Pluto, we were down to eight. Now astronomers believe there’s almost certainly a ninth after all. Quaintly, they are using the same logic that led them to search for Pluto a century ago.
Pluto’s existence was deduced from the skewed orbit of Uranus; now it’s oddities in the orbits of objects in the Kuiper belt (where Pluto resides) that point to a lurking lone giant up to 1,200 times more distant from the Sun than the Earth. Ten teams are training giant telescopes on its likely orbit and expect to nab it within the year.
So you may soon be learning new planet mnemonics along with the kids. You’ll also be discussing our new sister solar system: that of the red dwarf star Trappist-1, just 8% the size of our sun, and its seven “Earth-like” planets.
Trappist-1 is 39 light years or 369 trillion kilometres away – too far to travel to but close enough for space telescopes to get a good view of it while its planets whirl by, dimming its light. What is so exciting is that at least three of the seven planets are the right distance from the star for liquid water to exist. Life has a chance – especially since red dwarves, being so small, burn very slowly. Ten trillion years from now, when our solar system is long gone, Trappist -1 and its seven planets will still be around.
While we’re in space, let’s think about black holes. Hard to fathom, but at least I thought I understood one thing about them: they were the final stage of a very large star, after it had exploded and contracted its mass down to the size of something less than an atom. In other words, black holes were presumed to be the final chapter in the life of stars and galaxies.
Now, however, astrophysicists have evidence that supermassive black holes existed in the infant universe when galaxies were just being born. Instead of being epitaphs, black hole behemoths seem to have shaped our baby universe.
Finally to dinosaurs. Most of us know them from Steven Spielberg’s 1993 blockbuster Jurassic Park. Velociraptor was sort of accurate at the time (though about twice as large as the true Mongolian Velociraptor, more like North America’s Deinonychus). But the Jurassic sequels should have made the raptors fluffy, like baby chicks. Of course, that might have taken away their star power.
We know this largely from shocking discoveries that have taken place in China since 1996. The shocks have kept on coming.
Just when we thought dinosaurs couldn’t get any weirder, in 2015 Chinese palaeontologist superstar Xu Xing discovered a bird dinosaur with bat wings. It’s a brave palaeontologist who dares write a textbook these days.