In 2014, comet C/2013 A1, known as sliding spring, came within 140,000 Km of the planet Mars. This is a bit more than a third of the distance from the Earth to the Moon. Comets are small, so gravitationally this interaction was insignificant, but from an electromagnetic point of view, things were shaken up big time! Comets are small, relatively speaking. A typical comet is a few kilometers across, about the size of a big city. But with sunlight melting ices and liberating gases and dust from the comet’s interior, the part of the comet we see in the sky,...
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...
One of the first things you hear when learning about the states of matter is about good old H2O: Steam, Water, Ice. Naturally you are asked “Why does Ice float?” The answer is a simple matter of density, frozen water is less dense because water expands when it freezes. You can do a bit of an experiment by filling a balloon with water. Paint the balloon and put it in the freezer. When it freezes the water will expand, and so will the rubbery balloon, but the dried paint will crack at weak points. This is exactly the same thing...
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. ...
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...
Welcome to a new series of posts that will characterize 1000 amazing facts about the Universe. There is so much out there that we have yet to learn, and every day, astronomers across the globe are using their research to reveal the deepest secrets of the cosmos. This series will look at the strangest, coolest, most exciting facts that we have discovered in hundreds of years of modern science. Fact #5:When you see an aurora in the sky, it is a sign that you are being protected by the Earth and not being blasted with solar radiation. The Sun; A...
A few days ago I wrote about a galaxy that was tough to see because of Milky Way field stars. But our galaxy is far more than just a bunch of stars smattered about. There is also a huge amount of gas and dust with varying temperatures. Some of the hotter and more illuminated gas and dust are what make nebulae so lovely in space. But the cold gas and dark dust that is just out floating in the cold interstellar medium? That stuff gets in the way. A normal image of interacting galaxies M81 and M82 would try to hide the...
Welcome to a new series of posts that will characterize 1000 amazing facts about the Universe. There is so much out there that we have yet to learn, and every day, astronomers across the globe are using their research to reveal the deepest secrets of the cosmos. This series will look at the strangest, coolest, most exciting facts that we have discovered in hundreds of years of modern science. Fact #4: Most of the stars in the universe are red dwarfs smaller than our Sun. There is a leap of understanding that happens when a child learns that our Sun...
When you think of a nebula forming stars, it’s hard to imagine how large it is. Most nebulae form hundreds or even thousands of stars before being blown away by the young stellar winds. Pockets of a nebula collapse into dense regions that will eventually become stars with surrounding planetary systems. There are places in the galaxy we can look and actually see it happening. Pictured above, the beautiful ‘running chicken’ nebula, as strangely named as it is, is in the later stages of it’s star forming life. Many bright young stars have formed and their intense radiation is now...
We just saw it. Another record breaker. This incredible explosion of a massive dying star is the brightest supernova ever observed. You may think you get how big this explosion was, but it was brighter than collective brightness of all the 400 Billion stars in the Milky Way. You may be asking why you can’t see it in the sky. Well even though it is incredibly bright, it is 3.8 Billion light years away in a distant galaxy, so the discovery needed a huge telescope. It may have been powered by a rare star called a magnetar, a star with such an...
