Looking at the universe in radio waves is a fascinating sight. For one, the radio sky is very weak; If you placed your cellphone on the Moon facing back at Earth, it would be brighter than all other radio sources in the entire sky by a factor of a million. But as with every other part of the electromagnetic spectrum, it has scientific value in studying the sky. Over the past decade, astronomers have been identifying several Fast Radio Bursts (FRB), short bursts of radio waves from different places in the universe that last for a few short seconds. These are...
Baryonic matter, which is everything we are made of and everything we can see in the universe, is not a lot of stuff. I mean to a tiny Earthling, it’s a heck of a lot, but if you put it all together it only makes up about 5% of the total Mass-Energy in the Universe. If you’ve ever seen the Millennium simulation, it highlights the fact that both baryonic and dark matter are organized into filaments of mass, with the baryonic matter at the densest points, ie the galaxies. What lies between these dense nodes and filaments are vast empty...
On the outskirts of the Milky Way galaxy, its two major satellites can be seen, the large and small clouds of Magellan. Both considered irregular galaxies, they are more like swarms of stars, similar to gnats here on Earth. But even though they lack structure, they are still alive. The large magellanic cloud contains the single largest active star forming region in the entire local group of galaxies. This is the Tarantula Nebula. In the core of the tarantula, huge supernova shockwaves blast gas and dust, triggering star formation while forming dense filaments away from the center. Along the entire...
Galaxy NGC 4569 is a spiral galaxy that is part of the Virgo cluster, around 55 Million light years distant. Like any other spiral galaxy, we can learn about its motion through the cluster, the properties of its stellar population, and how quickly its converting gas and dust to stars. But this galaxy has an interesting property, it’s missing a lot of gas. For years, astronomers have had ideas about where the gas has gone, and with new data from the Canada-France-Hawaii Telescope (CFHT), they now have the answer. The gas is being stripped off of the galaxy, and is now...
When it comes to science communication, the most important thing to keep in mind is the perspective of the layperson, what someone will see, think, or understand if they have no prior knowledge. When you have some expert knowledge in science it can be hard to put it aside, but imagining the thought-process of a beginner gives you valuable information about how you are communicating, and can make a huge difference in your effectiveness. Which is why I am always thrilled to see things that communicate real science, yet stimulate the imagination. NASA, being a publicly funded organization, has to...
Gamma rays are the highest energy photons on the electromagnetic spectrum. Their wavelength is similar to the size of an atom, and when two of them collide they tend to produce a matter-antimatter particle pair. They represent energy high enough to synthesize the fundamental particles of matter, and are produced in the highest energy environments in the cosmos. The interchange of matter and energy works both ways, so one of the ways gamma rays are generated is through annihilation of a matter-antimatter particle pair. Looking back to the beginning of the universe it gives us the earliest ‘chicken or egg’...
A long time ago, in a galaxy far far away…. Two black holes, with masses 29 and 35 times the mass of the Sun, merged to form an even bigger black hole. The merger resulted in three entire suns worth of matter converted to pure energy in the form of gravitational waves. The waves travelled a billion light years before a tiny meat-filled species on a pale blue dot in space figured how to see them. Thanks to the smartest one that species had seen in a century, they knew that black holes might merge, and that they would produce these waves if...
I’ve covered a few ‘hidden galaxy’ stories lately, from the ultra high resolution see-through of Andromeda, to dark dust in front of M81 and M82. Now, hundreds of new hidden galaxies have been revealed by a team of astronomers who are looking straight through the Milky Way for the first time ever, shedding light on the structure of new galaxy clusters and the enigmatic pull of the ‘great attractor.’ The Earth is not stationary in space. It orbits the Sun, which in turn orbits the Milky Way galaxy, which then moves through the Universe as part of a galaxy cluster. ...
If you listen to an astronomer talk about a supernova, you’ll probably hear something along the lines of ‘A massive explosion of a massive star that is bright enough to outshine an entire galaxy.’ You can imagine how bright it might be, but it doesn’t really give you enough context to get the wow factor from it. Carl Sagan always said ‘When you make the finding yourself – even if you’re the last person on Earth to see the light – you’ll never forget it.’ Now you, dear reader, have the chance to make the discovery yourself. A series of images of galaxy...
Big stars tend to stick together. They all require incredibly dense regions in which to form, but once they do, they do a great job of blowing away and ionizing any other gas and dust in the vicinity. This is why nebulas in distant galaxies are great tracers of massive star formation. The bigger and hotter the star, the more UV light it produces, the more it ionized a gas cloud, the more we see gorgeous nebula. So it’s no surprise that when I look at the nebula below, I can guess that the central stars are huge, outweighing our...
