The Crab Nebula, as it’s commonly known, is connected to one of the earliest recorded supernova explosions. In 1054 AD, Chinese Astronomers saw the explosion of this supernova as an incredibly bright star in the sky lasting about two weeks, before fading. Now, nearly 1000 years later, the explosion is still happening as an expanding shock front rich in heavy elements moves through the interstellar medium. When the shock front hits dust or gas it is slowed down, giving the resulting nebula a unique shape. In this case, it looks like a crab. The supernova wasn’t exactly the death of the original...
We know that galaxies like our Milky Way are far more massive than we can see. The dark matter in the Milky Way makes up 90% of it’s total mass. Another way of saying this is the Mass to Light ratio, comparing the total mass inferred by the rotation speed of the galaxy to the total mass of stars in the galaxy. This ratio, M/L, for the Milky Way, is about 10. But for a galaxy cluster, the M/L ratio is more like 100. Galaxy clusters are not just dense collections of stars and massive galaxies, they are also immense...
Black holes are the most extreme phenomena known in the universe. They are the absolute limit of what gravity and space-time can be twisted into. It’s no surprise that some of the most massive and advanced telescopes in the world are tasked with studying their properties and how they interact with their environment. But maybe there’s a way for you and I to see what a black hole can do, and all we need is a moderate 8 inch telescope and our eyes! Even though black holes generally give off tons of radiation, we need to observe them in the...
In the early universe, there was a huge amount of swirling matter and light that didn’t really have much structure. Compared to today’s much more regular dotting of galaxy clusters and superclusters, the early universe was all over the place. But as will all things, there had to be a first. a first star, a first galaxy, and even a first galaxy cluster. The massive cluster of galaxies known as IDCS J1426.5+3508 is the most distant massive galaxy cluster ever discovered, and it has some interesting properties that point to how it formed and evolved so quickly. One such property is...
When Isaac Newton quantified gravity, his theory explained how everything in the world around us behaved in its presence. It opened a door to an understanding of something fundamental, yet elusive in explanation. Centuries later, Einstein came along and took a step back, finding a larger more comprehensive theory of gravity, one that explained the strange things that happen in the grand universe. His theory could even explain things that Newton’s theory of gravity could not, such as the odd orbit of Mercury around the Sun. But the greatest part of Einstein’s theory is that if you use it to...
This story popped up yesterday, and I can imagine it will go far, since it talks about life in the universe. I get it, it’s what people are interested in, and at least this story is focused on the science of why this is the best place to look for intelligent civilizations, instead of “Oh hey there’s a strange ring of material around a star, must be an alien superstructure.” But I digress. So where is the best place to look for life in the universe? The answer is in a Globular Cluster. A globular cluster is one of the...
As we rang in the new year, we were treated to a special astronomical appearance of Comet C/2013 US10 Catalina, close to the bright star Arcturus in the image below. Also visible near the top is the faint Comet P/19 Borrelly, and between the two comets is a bright meteor that swept through the scene. It’s remarkable to notice the clearly visible tales of Catalina, the blue ion tail sweeping directly away from the Sun due to solar wind pressure, and the dusty white tail marking the path of the comet. The dust is too heavy to be swept away...
Exoplanets are light years away, hidden by their parent stars, and barely detectable. Yet even though most have never been directly imaged, we can study the light from the parent star as the planet passes in front of it, and use this information to learn about the planet’s size and composition, especially if it has an atmosphere. Once you know a little bit about how big and dense a planet is, and the major elements that form it’s crust and atmosphere, you can do a lot of Chemistry to figure out what it should be made of and how these...
Some days at work, when I am in the Space hall at the Ontario Science Center, I take a close look at the golf-ball-sized Moon rock we have on display. I think about how this rock was brought back on an Apollo mission over 40 years ago, how it had been an untouched part of the Moon for Billions of years before this, and how it has taught us so much about how the Moon, and subsequently the Earth, formed. But now it’s time for a new generation of Moon rocks to be analyzed, and China is in the nation...
After talking about high resolution mapping of Ceres last week, it occurred to me that we have mapped so many distant worlds in our solar system. We have seen moons of Jupiter and Saturn up close, completely mapped Mars, and started mapping Pluto, pushing our boundaries of exploration. But what about our Moon? Sure the Earth-facing side has been seen in high definition. Anyone with a small telescope and a camera can take a great photo of the Moon. But what about the other side of the Moon, the so called dark side? It turns out that the Lunar Reconnaissance...