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...
The gravitational center of most objects and clusters in the universe are the place where the most massive and high energy interactions take place. For the solar system, the Sun’s core is hot and energetic. For star clusters, central regions host the most massive and brightest stars. For galaxy clusters, the most massive galaxies in the universe are seen in the center. And for individual galaxies, the Milky Way included, the core is where the fun happens. In the core of our galaxy, there are many massive and powerful objects, not limited to a supermassive star cluster, pulsars, supernova remnants,...
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,...
I love false-colour images. They reveal detail that you can’t see in real life, but they also highlight things in an artistic way. For me it’s an excellent marriage of art and science, and as a communicator it helps me get concepts across in an accessible way. So when I saw the APOD image of Saturn from earlier this week, I had to discuss it. Saturn never has looked this way, and it never will. The colours are vivid and unrealistic, but they show the differences in three distinct but close wavelengths of light on the electromagnetic spectrum. All of...
I’ve spent the last couple of days as a zombie due to the time change, but now that I feel like myself, I’ve got some catch-up posts to do. The first one has to do with today’s APOD. Can you spot the phoenix shape? It doesn’t mean anything special, it’s just the way our brains see the patterns of light from this gorgeous aurora in Iceland. Ionization of atmospheric gases from charged solar particles doesn’t sound as glamorous as ‘phoenix aurora,’ but I still appreciate the scientific beauty of it. Human beings are excellent at pattern recognition, and so we...
Space seems dark to our weak human eyes. Most of the night sky is the blackness between stars. But in this darkness lies an endless number of photons, travelling in all different directions. These photos form background radiation, in three wavelengths in particular. You’ve likely heard of the Cosmic Microwave Background (CMB), it there is also a Cosmic Optical Background (COB) and a Cosmic Infrared Background (CIB). The COB is explained by the immense number of stars in the Universe. It’s a diffuse glow across the entire sky. The CMB is the leftover radiation from hot plasma that existed when the Universe...
Whether you’re looking for an excuse to eat dessert or just love mathematics, March 14th is a good day for geeks, nerds, and the rest of the world too. The third month and the fourteenth day, 3.14, is known as Pi day, after the simplest and most ubiquitous constant in nature (no disrespect to c, e, g, or h). Defined as the ratio of a circle’s circumference and it’s diameter, Pi is an irrational number, meaning there is no end to its digits. Most people know 3.14159, but some people have memorized hundreds more digits. Mathematicians armed with supercomputers have calculated Pi to...
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...
Can we grow crops on the Moon? How about Mars? If you saw the movie “The Martian,” it seems you could grow potatoes on Mars with a supply of water, oxygen, and some fertilizer, but without these necessities (soil nutrients, water, oxygen) they just wouldn’t last. If we eventually want to colonize places like the Moon and Mars, finding a way to live off the land is a must. The sunshine will help, but can we really grow crops on alien soil? As it turns out, Earth scientists have been working on this problem, by simulating the soils of the...
You know the thing I mean, when it suddenly goes dark in the middle of the day and looks all fiery. Stars come out in the daytime and animals go crazy. When silly people pray extra hard for some reason. I swear the Moon is involved. It looks like this…. Ah yes the solar eclipse, the rare event that only occurs because the Sun is both 400 times wider and 400 times more distant than the Moon. It’s a mathematically beautiful event that only occurs every 5 years on average. And when it does happen, the total coverage of the...
