Lurking in the depths of a galaxy, hidden from human eyes, lie millions of monsters. They could swallow you up in an instant, sealing you off from the outside world and devouring you atom by atom. This sounds like your typical Hollywood monster movie, but with millions of black holes hidden throughout the galaxy, its more real than you might think. Supermassive black holes, the largest ones that reside at the centers of galaxies, are much easier to see. They are devouring gas and dust rapidly, resulting in bright emission across the electromagnetic spectrum, especially in x-rays. For many galaxies,...
It’s always nice to know that amazing science is being done in local institutions. Here in Ontario, Canada, we have 24 universities, and I had the pleasure of attending two of them, giving me a first hand look at the day to day work of astronomers. It certainly helped me realize how hard scientists work to get one simple result that the public will only care about for a day or two. About 95% of the work, from grant writing to data acquisition to data reduction to analysis and interpretation, is behind the scenes, and the final 5%, the result,...
When the first stars and galaxies started to form, it was like a spark of a massive chain reaction where the vast amounts of gas and dust that had clumped together were quickly converted into dense, luminous star clusters. This was the beginning of the formation of the heavier elements that would eventually make up all that we see on the planet Earth. But when did this massive tirade of star formation end? When we look at galaxies in the present epoch, most don’t form stars very rapidly at all, and giant elliptical galaxies are all but devoid of gas,...
After yesterday’s post about some data that has caused us to rethink a theory, I wanted to follow it up today with an even bigger bit of data that could substantially change an even bigger theory. Dark energy was discovered as a large-scale repulsive force in the universe that is responsible for the acceleration of its expansion. It was discovered by looking at type 1a supernovae in distant galaxies. since the supernovae all explode with the same mass limit, they appear to all have the same intrinsic luminosity. If we know how bright they actually are, we can compare them...
We call it dark matter because it doesn’t give off light, right? Well there is a lot of matter than doesn’t radiate, but the difference is that whatever the stuff is that we call dark matter doesn’t interact with anything through the small-scale fundamental forces. The only way we have been able to detect it’s presence is through large-scale gravitational interaction. Dark matter is ‘dark’ because it doesn’t interact with anything in a way that lets us figure out what it’s made of. Well now that we’ve got that out of the way, we can look at the new...
The biggest problem in theoretical physics today is the marriage between Quantum Mechanics and Gravity. Throw in the fact that whatever theory comes out of it has to additionally be able to explain Dark Matter and Dark Energy, and we have ourselves a massive problem to solve. How do we reconcile the seemingly random probabilistic nature of quantum mechanics with the smooth, pliable space-time of General Relativity. We have two incredible theories that explain the Universe, make predictions accurately, and have led to amazing advances in technology and understanding, yet they completely disagree with each other at common scales. So...
Image submitted to an image processing competition called ‘Hubble’s Hidden Treasures’ are expected to be amazing, but this is the only one I’ve seen that will make you happier. This cosmic ‘smile’ is in the constellation Ursa Major, and is made up of the light from four galaxies, each with Billions of their own stars. This is the biggest happy face ever found! The two eyes are very distant galaxies known as SDSSCGB 8842.3 and SDSSCGB 8842.4. So why do we see this ring structure? You might think that the Galaxy is stretched by gravity, but its something much more...
New research using the ESA’s Planck telescope has revealed that the first stars to shine in the universe sprouted up 100 Million years later than originally thought. Studying the universe is like piecing together a 13.8 Billion year story, from the time of the Big Bang to the present. We study objects in the local Galaxy to piece together the present state, and we look further from Earth to see back in time and visit the earlier chapters to determine the long term evolution of the universe. When the universe was 380,000 years old, it was large enough for the...
Last year we received some incredible news about Cosmology and the Big Bang. An experiment devised to find the signature of the inflationary model of the Universe told the world they had done it! The world cheers, as did many scientists; but of course there are always reasons to be sceptical, especially with claims that have such an impact for humanity let alone the science world. And now it seems the scepticism was correct, as the conclusive result has now been deemed inconclusive. This doesn’t mean its false, not by a long shot, but it does mean the research team...
A vast number of Galaxies in the Universe have a central black hole that is incredibly massive. The Black Hole at the centre of the Milky Way, dubbed Sag A*, is estimated to have a mass as high as three Million Suns. We generally can’t see black holes, but when they start to pull in matter from surrounding gas and dust clouds, the material forms a disk around the star. This accretion disk can heat up to incredible temperatures and emit X-rays and other high energy light, allowing us to see where the black holes are. Sometimes the light from...
