Even I was blown away when I saw this image a friend sent me. Gravitational lensing is a rare occurrence, and a supernova is a rare occurrence, so to see a supernova in a gravitationally lensed galaxy deep within the universe is exceptional. So exceptional that it was spotted for the first time ever in a Hubble image of the distant universe. That dot in the image is a single supernova in a very distant galaxy, split into four images by the gravitational lensing of the galaxy cluster in front of it. But there is also a secondary lensing effect from...
There is a loose hierarchy of the cosmos that repeats. Stars form clusters, and then galaxies. Galaxies form clusters, and then these form clusters of their own, called superclusters. Gravity dominates the structure of such collections, yet all we feel and see from Earth is a relatively homogeneous distribution of stars. How do we see this hierarchy? If we zoom in, looking at a patch of sky so tiny that we can’t see any stars, what do we see? This patch of sky is about the size of a grain of sand held at arm’s length, and if we point the...
The thing about black holes is that they are very dense. If we took the entire 2,000,000,000,000,000,000,000,000,000,000 Kg of the Sun (This is the real mass of the Sun) and turned it into a black hole, it would be about 6 Km in diameter. It is theorized that there are around 100 Million Black holes in the Milky Way Galaxy alone. But if they aren’t near a large reservoir of gas and dust, with their small size they are pretty harmless and invisible. The only way we could find them would be through their gravitational influence, which is hard to...
Every single massive galaxy has a black hole at its center, and bigger galaxies have bigger black holes. It almost seems like a natural progression, with a bigger galaxy meaning more stars and material to feed a bigger black hole. However, most of that material doesn’t make it to the central black hole. So how does a massive galaxy with hundreds of billions of stars spread out over hundreds of thousands of light years contribute to a black hole that at most is solar system sized? The answer might lie in another elusive and enigmatic gem of the universe: Dark...
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...
When I became a Masters student, a big part of the reason I liked the supervisor I had was that she studied M31: The Andromeda Galaxy. Since I was young I was obsessed with finding this galaxy in a telescope, and I will never forget the night I first found it. Seeing that strange fuzzy patch, photons that had travelled for 2.5 Million years through space, it was my first ever experience with ‘time travel’. Consequently, it makes sense that I am excited about a recent Hubble release: the highest resolution photo of the Andromeda Galaxy Ever taken. Let’s start...
You might think simulating the entire Universe is difficult, and it is, but not for the reasons you would think. The Physics is actually somewhat straightforward. We know the math behind star formation, Gravity, and fluid dynamics, and throwing in a few other effects is not too bad. The hard part is finding a computer powerful enough to do the calculations in a reasonable amount of time. Think about it. Imagine having a universe of 100 Billion ‘particles’ used for a simulation. Each particle has a starting point, and that it pretty easy to do. But then for every...
Pictures can say a thousand words, and the Astronomy Picture of the Day from NASA usually does. Today’s photo shows massive perspective, from the ground a pretty large observatory is visible, yet it pales in comparison to the vast mountain range in the background. Further still is the structure that makes all human experience seem minuscule: The Milky Way Galaxy.
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...
