Last week, while looking at some of the best images from the Cassini spacecraft, I commented on the fact that the smooth rings of Saturn are small, varied chunks of ice and rock when you get down to the smaller scales. Reflecting on that this morning, I was thinking about how observing objects in our universe at smaller scales gives new insight into the variety and complexity of natural phenomena. Not long after, I came across a story of a new interesting object in our own Solar System. A new binary asteroid was discovered. This in itself isn’t too different...
Why does the Sun seem red near the horizon? Why does the Moon do the same? We know the Moon isn’t actually changing colour, and the Sun isn’t either. So what is happening to the light? The first thing to note about the image above is that the size of the Moon doesn’t change, showing that the well-known ‘Moon Illusion,’ where the Moon appears larger near the horizon, is just that – an illusion. The second is of course the gradual change in hue as the Moon rises. The reason for the colour shift really has nothing to do with the Moon...
Every time we see amazing photos of galaxies or planetary disks, we can see most of the detail since we see them face on. But since the orientation of spiral galaxies in the universe is random, there are a plethora of galaxies ignored by image processors since we just can’t see much of the detail. We can still learn from edge-on spiral galaxies, just not as much as we can from those that are face on. We can see some fascinating dust lanes in the image above, and a ton of detail considering the view, but we don’t know what...
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...
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...
How do the Mars rovers compare in size and features? Here’s a great photo putting it all into perspective. Included are Sojourner, Spirit/Opportunity, and Curiosity, with a couple of testing officials at NASA’s Jet Propulsion Laboratory. These are not the rovers that were sent to Mars, but are the secondary ones built for testing here on Earth. They cost a lot of money to build too, so NASA keeps them nice and safe.
Some of the most gorgeous, ghostly, and variable objects in the universe are planetary nebulae. They are all formed in a similar process, as a low-mass star (like our Sun) sheds it’s outer layers of gas and dust, heating them to a glow as they disperse over hundreds of millions of years. A few Billion years from now, the Sun will undergo the same major state change. When this happens, perhaps other species in the far future will gaze upon it and marvel at its beauty. One of the difficulties in studying a planetary nebula is measuring it’s distance from...
Out of the over 2000 confirmed exoplanets, not one has been seen in the conventional sense, where we would see it’s surface, map out features and colours, and understand it’s atmosphere or surface from what we saw. Instead all the knowledge we have of exoplanets is based on the light we see. How big is the dip in the Kepler Telescope’s light curve? What absorption features do the reflected light of this planet show? This information is the result of careful analysis and brilliant inference, since the planets themselves are immeasurably tiny and hard to spot next to their giant...
If you have ever seen the Andromeda Galaxy, M31, in the sky or through a telescope, you’ll find it’s reminiscent of a small blurry, fuzzy patch, almost like a cloud. The cloudy look is similar to looking at the hazy white glow of the milky way’s concentrated disk. But that cloudy view is not all of M31. The galaxy is so far away, around 2.5 Million light years, that you’re only seeing the concentrated light from its central bulge. You’re actually missing a large portion of the galaxy because its just too dim for your eyes to see. If you can take a...
Categorizing objects in the universe can be difficult. The fiasco with Pluto over the last decade is more than proof of that. We generally look to location and then to size as the two main methods for classifying the stuff that permeates the cosmos. Galaxies contain stars, which host orbiting planets, which host orbiting moons; While asteroids fly in between planets and icy comets are wander through the outskirts of star systems. But what about the in-between objects? Often we find strange things in strange places. There are moons in our solar system that are larger than planets. What would...
