1,200 Km / s. That’s fast. Fast enough to race around the entire Earth in 30 seconds. Except that it’s not a bullet, it’s a star, larger and more massive than the Earth. And a multinational team of astronomers has discovered it, and more importantly, where it came from and why it’s moving so fast. Hypervelocity stars (HVS’) are an uncommon phenomenon, since the conditions necessary to accelerate them to incredible speeds are rare. There are only about 20 HVS known, and the first was found only ten years ago. So where do they come from? There are only a...
It’s not often that we find new star clusters within our own Galaxy. Technology has been good enough to see the stars in the Milky Way for decades, and the grunt work in identifying and cataloguing local clusters is more or less finished, but occasionally we get lucky. A tiny and extremely distant globular star cluster has been found in the outskirts of the far side of our home galaxy. Currently named Kim 2, it pales in comparison to the other 150 Milky Way globular clusters, containing 10-20 times fewer stars and having less than half the stellar density. The...
At least once a month we hear of a new exoplanet with a strange and amazing story. From the ‘Super-Saturn’ ringed world to Magnetic Fields to systems of three Earths, there is an abundance of planets and strange systems. The latest weird discovery brings us to a star 1,500 light years away in the constellation Cygnus. The small-Mercury sized planet it hosts orbits in only 16 hours, bringing its surface temperature to over 1,800 degrees celsius. This amount of heat is enough to vapourize rock, and so the star is literally roasting the planet and blasting away its surface. The dust...
Like piecing together a car accident, by looking at the results of a collision in space, we can use our knowledge of science to piece together the past and determine what happened to a high degree of accuracy. The velocity of a star, along with high powered computer simulations and statistical techniques, can help us determine where it once was. But since space is so vast, why do we care where stars have moved? The short answer is that there are so many stars out there that we don’t often care where individual stars have moved. Some exceptions are when...
For Christmas I was given a green 200 mW laser! A couple of AAA batteries later and the laser can point out any star or object in the night sky, with the beam clearly visible the entire way up to infinity. Its the epitome of an Astronomer’s toolkit, at least in my eyes, and it got me thinking about all the amazing things you can see in the sky right now. It also makes me feel like I’m brandishing a light saber, and sadly it’s about as close as I’ll ever get. First off, Venus is back in the evening...
A set of questions I get from kids and adults alike while doing my Astronomy in Action planetarium shows consists of the following: Does the Universe have an end? How big is the Universe? Where is the center of the Universe? What is the ‘Observable Universe?’ How is it different from just saying ‘the Universe?’ First of all, let me say that it is really hard to imagine the Universe as it is, even with a solid understanding of large-scale Physics. This is because there is no analogy in our lives, no reference point in our everyday experience. It’s very...
Yesterday I wrote about young stars that had a habitable zone further away than we thought, and how this would help us spot habitable planets more easily in the future. Today is the second news story this week dealing with finding planets, and it deals with more familiar Sun-like stars and their dusty planetary discs. Dust is both a good thing and a bad thing when looking for planets orbiting other stars. Dust tells us that there is a high likelihood of finding planets, but too much dust blocks out the planets that we look for. Warm dust is worse...
Space is Big. I say this often, but it is so vast we can’t even comprehend the emptiness of it. We see Billions upon Billions of stars, all taunting us with their shine, seemingly close but completely unreachable. How do we know which stars we should spend our time looking at? We don’t really have the time to scan through each star in detail, so what are the criteria for taking a closer look? Generally we look at a population of stars to gain an understanding of each life stage, and then we look at the oldest and youngest to determine...
When I do Planetarium shows, one of the things I like to talk about during the Milky Way – Andromeda collision that will happen in 70 Mlllion years, is the fact that very few stars will actually hit each other. Yet we still call it a ‘Galaxy collision.’ One of the questions I always get is “Will the Earth survive this?” I usually ask the audience. The response is usually a unanimous ‘No way!” And then I tell them how big Galaxies are and they can’t believe how unlikely it is that the solar system will be affected. Consider the...
About 170 years ago, a star nearly exploded in the Southern constellation Carina. I say nearly for a few reasons. On Earth, observers saw a dim, seemingly-average star become the second brightest star in the night sky. It stayed that way for 20 years before slowly fading. When we looked at it with telescopes, we found that whatever happened to Eta Carinae, it ejected more than 30 times the mass of our Sun in that short twenty year period, creating what we now call the homunculus nebula. Eta Carinae is a multiple star system 7500 light years away from Earth, so rest assured any...
