Cosmic rays are incredibly powerful invisible particles, and we can’t be sure where they come from. Not much in the way of a comforting thought, but it makes for a cosmic mystery that astronomers have been trying to solve for decades. And now they have come one step closer. Here’s what we do know. Cosmic rays are energetic atomic nuclei travelling at near the speed of light. They hit our atmosphere and rapidly interact with the molecules there to break into billions of smaller, less energetic particles that shower down on the life on Earth, without giving us much notice...
As the search for planets in the galaxy continues, there are two places to focus on: Distant stars with potential large planets, and nearby stars with potential small planets. If we are able to find Earth-like planets orbiting nearby stars, they will be prime targets for future generations to explore. Astronomers have just announced the discovery of three new planets orbiting a star only 40 light years from Earth. The star is a very small red dwarf, only slightly larger than Jupiter, and even though it’s close to Earth, it can’t be seen with the naked eye or even with a large...
What is the difference between a comet and an asteroid? The typical response is that an asteroid is rocky and a comet is icy/gassy. Further than this, asteroids typically orbit closer to the Sun than Neptune, and comets orbit beyond this loose dividing line. But as with everything in nature, there are often exceptions to the rule. C/2014 S3 PANSTAARS is classified as a weakly active comet, originating in the Oort cloud with an orbital period of 860 years. As it approached the Sun, astronomers noticed that it was lacking the characteristic comet tail, resulting from the blast of solar radiation upon approach to the...
The closest star to the Earth, aside from the Sun, is Proxima Centauri, a small red dwarf star that is part of the Alpha Centauri system, roughly 4 light years away. If you don’t know light years, the distance is a staggering 37,800,000,000,000 Km. Beyond that our stellar neighbourhood fills in as you move 20 light years in any direction, and by 100 light years, there are dozens of stars around us. This gives a stellar density of about 0.14 stars per cubic parsec (a parsec is about 3.26 light years), pretty normal in terms of the number of stars in a given...
Not to be confused with Canadian Gum Hubba-Bubba, Hubble has released a great birthday image for it’s 26th birthday. I’m a few days late to celebrate, but it’s still a beautiful image. Known as NGC 7653, the Bubble nebula is 8,000 light years distant in the constellation of Cassiopeia. The reason for this natural bubble shape is that the star just left of center in the image is ionizing a surrounding cloud of Hydrogen with it’s powerful stellar wind. As electrons and protons recombine at the edges of the bubble, they release an infrared photon that can be clearly seen...
If a supernova were to go off somewhere in our galaxy, the minimum safe distance for Earthbound life would be about 50 light years. Any closer than that, and we would experience an intense blast of high energy radiation and an eventual shower of radioactive particles. It would be like nuclear bombs were set off all around the Earth, causing little destruction but a lot of radioactive fallout. Supernovae are incredibly powerful to be able to cause such damage at 50 light years, but even at larger distances, we can see evidence of their effects here on Earth. A team of...
With the recent discovery of gravitational waves, we now have a target for probing the very early universe, close to the big bang. This is because gravitational waves can travel across the universe unimpeded, meaning those created after the big bang are still bouncing around today. It’s like the big bang was the ringing of a giant bell, and the ringing can still be heard. But all of our Easter eggs are not in one basket. There is another way to probe the very early universe, one we haven’t found yet, because it involves particles that are very tiny and...
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...
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...
