Remember last week when I was talking about the evidence for some ancient-but-astronomically-recent supernovae? It turns out there is other evidence! Evidence that has helped scientists narrow down the potential source locations. Data from the Cosmic Ray Isotope Spectrometer (CRIS), an instrument aboard NASA’s Advanced Composition Explorer (ACE) spacecraft, has helped us figure out where the recent supernovae might have come from. CRIS measures what we call cosmic rays, atomic nuclei that have been accelerated across the galaxy at close to the speed of light. CRIS has been around for a while, and through 17 years of cosmic ray observations,...
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...
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...
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...
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...
One of the greatest scientific discoveries of all time came with the invention of the spectroscope by Joseph Von Fraunhofer in 1814. It enabled us to look out at the universe and realize that the same basic building blocks that made you and I and all other life, were the same things that make up everything else in the cosmos. The tiny atoms in our bodies all started out at the center of a massive star billions of years ago. So naturally, when we talk about the odds of life forming elsewhere, we have to include a study of where...
Deep within the Earth, far below the layers of rock that form the crust, and even further below the molten rock of the mantle, lies a hot core of Iron and Nickel. The swirling of the liquid metal creates a flow of charge and produces the magnetic field of the Earth, without which we humans could not survive. But there is still more. At the centre of the Earth, a part of the liquid metal core, the size of Pluto, cooled into a solid ball of Iron and Nickel. When in the Earth’s history did it form? This question has...
Think about Earth and its population of over 7 Billion people. That’s 7 Billion people who wake up, breathe, live, think, experience, and interact with each other. The sheer volume of interactions and variation in the human experience is staggering. Every second you are alive these interactions are happening all around you, and far from you in any corner of the planet. Millions of people right now feel sad, happy, ecstatic, broken, angry, tired, energetic, and everything in between. Now if we go beyond to the Milky Way, where there are more than 50 stars for each and every homo sapiens on...
Mercury, the smallest planet in the solar system, and closest to the Sun, is only a little bit bigger than Earth’s Moon. But the Moon is comparatively reflective object. Mercury is thought to be made of the same rock as the Moon, so what is the difference? Why do objects in our Solar system have different brightnesses? The key is in a property called albedo. It’s basically how much light an object reflects, measured as a fraction. For example, the Moon reflects 12% of the light the Sun shines on it, so it has an albedo of 0.12. The albedo...
Astronomy is a science that is always associated with the sky, and rightly so. But since the beginning of modern science there have been discoveries made on Earth that teach us about the formation and evolution of the Universe. As telescopes become more powerful and allow us to look deeper into space, the technology to simulate outer-space conditions here on Earth has grown significantly. In Albuquerque, New Mexico, a powerful tool called the Z machine generates quick high-energy pulses of electricity, which can be used to generate X-rays and Gamma rays to be used in experiments. Outside of astronomy, the...
