It’s difficult to determine the history of the Solar System. The planets have been in their current orbits for Billions of years, and any signs of prior activity or configuration has to come from leftover geologies of smaller, rocky worlds. It makes it especially difficult when the Billions of interloper asteroids and comets throughout history have to be accounted for, adding to the already complex task. But if there is one thing humanity has going for us it’s the ability to theorize, model, simulate, and test scenarios here on Earth. We can try new ideas and see if they match...
We have found evidence of ancient impacts all across the Earth, from the famous Chixulub crater in Mexico to the Sudbury Basin a little bit closer to my home. From Space the remains look nothing like craters, millions of years of sediment and growth hide the massive regions from obvious detection, but signs remain of these massive events, even after millions of years. This week, what is possibly the largest impact crater basin ever discovered has been found in central Australia. And it is thought to originate from the breakup of a massive 400 Km asteroid into two pieces that...
Every 29.5 days we see a new Moon, or rather we don’t see it, since it’s lost in the glare of the Sun. But a few days after the new moon, we can see it slowly move away from the Sun and become visible after sunset, with the thinnest crescent growing a bit larger each night. You may have heard that Mars and Venus also live in the Western sky after sunset, with Venus moving higher and Mars appearing to double back toward the Sun, soon to be lost in the glare of our home star. Last night I was...
As the Rosetta spacecraft remains in orbit around the comet 67P/Churyumov-Gerasimenko, the comet is slowly drifting toward its closest approach to the Sun, known as perihelion. As the comet moves closer to the Sun, intense sunlight liberates gases and dust in streams of material that form clearly visible streaks. The orbiter is able to sample some of the material liberated from the comet, and for the first time it has seen the tell-tale signature of Molecular Nitrogen. Nitrogen is abundant on Earth as a gas, constituting the majority of our atmosphere. It is also present in the atmospheres of Pluto and Neptune’s...
With all the talk of the large geomagnetic storm of the past few days, it’s important to understand that other worlds have beautiful auroral activity as well. Being on Earth and seeing the gorgeous displays that result from our magnetic field protecting us from harmful solar radiation, the best views come from Earth. But there are several other places in our own solar system that have aurora. Jupiter has a massive magnetic field, and its gigantic aurora are visible here. Jupiter’s moon Ganymede is the only moon in the solar system that has auroral activity. Saturn has its own, discovered...
Aurora Borealis (Northern Lights) and Aurora Australis (Southern Lights) are the most beautiful result of the Earth protecting us from a horrible death by solar radiation. Every time I see it, I marvel in the beauty and remind myself that I am still safe from being cooked by that giant ball of gas that is responsible for fundamentally fuelling all life on Earth. So when we have a lot of auroral activity, I pop over to spaceweather to see if it will be visible from where I live. Though it usually isn’t, today’s aurora are potentially visible, so I might...
Over the course of a day the Earth changes quite a lot. Lightning strikes the Earth 8 Million times per day as the mighty water cycle on our planet churns under the power of the Sun’s warmth and the Coriolis force on the Earth. But have we ever just stared at the Earth’s surface over the course of the day? Definitely. We have seen the day to day changes from many different altitudes above the Earth’s surface, and the above image shows stunning changes over the course of a day. But how do we get a picture like this?...
After reaching a deeper understanding of the subsurface ocean of Enceladus just yesterday, a stunning discovery has just been made about the largest Moon in the solar system. The largest moon of Jupiter, Ganymede, contains a subsurface ocean of it’s own. The discovery was made with the Hubble space telescope and a careful study of aurora on the giant moon. That’s right Ganymede has auroral activity. This is because it is the only moon in the solar system with a magnetic field. The magnetic field funnels radiation from the Sun toward the north and south poles, where it ionizes molecules...
I love to discuss Mars rovers. The thought of robots roaming around the empty red desert, doing science in pure form, unmasking the surprising history of our red neighbour, it’s exciting and it’s the frontier of discovery. The limits of science and engineering are pushed as we send complex machines to travel further than any human in history. But with such a marvellous feat, issues can arise, and when they do, the nearest mechanic is 55 Million Km away. On February 27th, during the transfer of a sample of dust from the rover’s drill to its instruments, the rover suffered...
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...
