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...
Some of the moons of gas giant planets have a unique property: They are worlds that have a source of heat other than the Sun. The huge tidal forces imparted by their host planet and fellow moons cause their crust to grow and shrink, creating huge friction and heating the rock. It means that even if these moons are far from the warmth of the Sun, they can still host liquid water. There are two moons in our own solar system that are especially enticing: Jupiter’s second moon Europa, and the icy moon of Saturn known as Enceladus. Each host...
The thing about black holes is that they are very dense. If we took the entire 2,000,000,000,000,000,000,000,000,000,000 Kg of the Sun (This is the real mass of the Sun) and turned it into a black hole, it would be about 6 Km in diameter. It is theorized that there are around 100 Million Black holes in the Milky Way Galaxy alone. But if they aren’t near a large reservoir of gas and dust, with their small size they are pretty harmless and invisible. The only way we could find them would be through their gravitational influence, which is hard to...
The Sun is the driving force behind our planetary system. It’s energy warms our planet, drives weather and climate patterns, and fuels the aurorae that surround our magnetic poles. The Sun also has a much grander sphere of influence beyond the orbit of the Earth, stretching into the vast space between itself and the other members of the stellar neighbourhood. The charged particles that are released from the Sun, called the solar wind, stretch out to 120 Astronomical Units, about 18 Billion Km. The bubble of the Sun’s influence is known as the Heliosphere, though it is anything but a...
Like piecing together a car accident, by looking at the results of a collision in space, we can use our knowledge of science to piece together the past and determine what happened to a high degree of accuracy. The velocity of a star, along with high powered computer simulations and statistical techniques, can help us determine where it once was. But since space is so vast, why do we care where stars have moved? The short answer is that there are so many stars out there that we don’t often care where individual stars have moved. Some exceptions are when...
This amazing video from animator Alphonse Swineheart gives us an idea of the vastness of space, showing how incredibly large our solar system is. There are a few long trips between planets, but some fun facts keep it interesting. Plus the point is that we are getting an idea of the scale of it all. One thing to keep in mind is that each second the viewer is travelling 300,000 Km, equivalent to circumnavigating the Earth almost 8 times! A good thing to remember is that if we were seeing the distance to the next star, proxima centauri, this video...
There has been a lot of planetary news lately, in our own solar system and beyond. With the DAWN spacecraft approaching Ceres, New Horizons finally reaching Pluto in a few months, and the Kepler Space Telescope giving results from it’s new observing run. Not to mention comet Lovejoy, Mars Rover anniversary, and the Venus Metal Frost story. Normally I would pass on so much planetary news, even though it is one of my favourite areas of Astronomy. This story, however, is just too good to pass up. Kepler 444, a very ancient star 117 light years from Earth, about 25% smaller than...
When the temperature is just right, and the sky is clear, you can see some amazing phenomenon from the Sun. It isn’t your eyes playing a trick on you, it just means you’re seeing the right conditions for a really amazing experience. Sun Dogs, known scientifically as Parhelia, typically appear as two bright patches on either side of the Sun. Occasionally they reveal rainbow colours in their pattern, but can be quite bright. They are most easily visible when the Sun is low in the sky. Sun Dogs are made from the refraction of ice crystals in the upper atmosphere....
