Black holes form when a massive star runs out of fuel. Gravity causes the core to collapse down to an object so dense that light itself can not escape. In the Milky Way galaxy, there are expected to be over 100 Million black holes, though of course we can’t see them. The one we can see is the supermassive black hole Sag A*, lying deep within the core of the galaxy. But how did Sag A* form? Was it from the merger of many smaller black holes? Or is there some other process forming the most enigmatic objects in the...
I feel like I’ve been covering a lot of stories on magnetic fields over the past few months. Fields around the Earth, the Sun, Mars, Jupiter’s Moons, and exoplanets are just some of the places in the universe where we are looking at magnetic field behaviour. The intention is to use our understanding of magnetism to figure out what is inside these worlds, and how they interact with their space environment. You would expect us to understand the Earth’s magnetic field and interior very well, after all, we are stuck here. But it turns out it’s very difficult to study the interior of...
Data is fascinating. And what’s even more fascinating is that the laws of nature produce predictable patterns in data. For example, if you toss a coin 100 times and measure how many times heads comes up, you’ll get a number between zero and 100. If you repeat that experiment again and again and again, you’ll get different values each time, but usually the number will be around 50, and 50 will come up more than any other value if you repeat the experiment enough times. If you plot this data, with the # of heads in 100 coin tosses on...
Gold doesn’t come from your local jewelry store, and the Gold rush that occurred in the Yukon territory at the turn of the 20th century is not the source I’m talking about either. I want to take it further back, to the origins of gold the element. Similar to the origins of most other elements on the periodic table, it requires an immense amount of energy, such as the nuclear fusion that goes on within a star. But Gold can not be made by a star’s thermonuclear engine. Gold requires more energy, as does every other element heavier than Iron. So...
As I’ve said before, the most powerful, most energetic, most intense processes happen in the center. The gravitational center of the Earth, the Sun, and the galaxy are all places where temperature, pressure, and interactions of matter and energy are pushed to their limits. When you look up to the sky it’s easy to see the Milky Way (unless you live in an urban center). Do you ever wonder where the middle of it is? Where that supermassive black hole lies? Astronomers know where it is, but you need infrared cameras to see it past the thick dust that blocks...
One of the most surprising and intriguing finds during the decade-long Cassini mission has been the discovery of geysers on the Moon Enceladus. Originally spotted in 2005, scientists have spent the last decade trying to understand how they work. And now they finally have a working model. How does an eruption on a frigid Moon last so long? Eruptions on Earth are not long-lived, and if they are, they are very spread out. For Enceladus to have a ton of localized geysers in the South polar region, you need some pretty specific scenarios. Aside from the fact that a constant stream of material could clog...
I just released a post about the Kepler Space Telescope and its observation of the shock breakout of an exploding star, the exact moment when it’s considered a supernova. Further to this I wanted to show some of the great visualizations of the event, and to show you just how energetic and luminous a supernova really is, compared to our Sun. The video shows the shock breakout, the bright flash lasting an hour, before the star rapidly increases in brightness to it’s maximum. Not shown is the gradual fading of the supernova, which can take days or even weeks....
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,...
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...