Mars is a planet wide desert with underground and polar cap water, but it’s general arid environment and occasional wind give rise to dusty weather events such as tornado-like dust devils and local dust storms. Every so often, one of these little dust storms expands and becomes a planet wide phenomena, and in early June this is exactly what happened. So what does it mean for our rovers and orbiters? Global dust storms are a recurring phenomenon on Mars, and happen regularly about the planet regardless of season. Every 3-4 Martian years (6-8 Earth years) one of these smaller storms...
As I was watching the grand finale of Cassini and listening to the mission team talk about the accomplishments of the mission, I learned a little bit about propellors. Not your typical airplane propellor, but the name used to describe this fascinating feature in Saturn’s rings. Seeing Saturn’s rings from afar, or even relatively close with Cassini, we see the rings as perfect. How do we end up with strange features and imperfections like this one? Looking elsewhere in the rings, we can find clues. The first clue is the namesake of the mission itself. The Cassini spacecraft was named for...
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...
I’ve spent the last couple of days as a zombie due to the time change, but now that I feel like myself, I’ve got some catch-up posts to do. The first one has to do with today’s APOD. Can you spot the phoenix shape? It doesn’t mean anything special, it’s just the way our brains see the patterns of light from this gorgeous aurora in Iceland. Ionization of atmospheric gases from charged solar particles doesn’t sound as glamorous as ‘phoenix aurora,’ but I still appreciate the scientific beauty of it. Human beings are excellent at pattern recognition, and so we...
Gamma rays are the highest energy photons on the electromagnetic spectrum. Their wavelength is similar to the size of an atom, and when two of them collide they tend to produce a matter-antimatter particle pair. They represent energy high enough to synthesize the fundamental particles of matter, and are produced in the highest energy environments in the cosmos. The interchange of matter and energy works both ways, so one of the ways gamma rays are generated is through annihilation of a matter-antimatter particle pair. Looking back to the beginning of the universe it gives us the earliest ‘chicken or egg’...
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...
Every year, as the Earth revolves around the Sun, we pass an imaginary line directly from the Sun to Saturn. The Sun is on one side of us and Saturn is on the other. When two bodies are on opposite sides of the Earth like this we call it opposition. Saturn’s opposition for the year was on May 23rd, and even though it has been a few days, you can still see Saturn up pretty much all night. Along with opposition, we can clearly see the rings, but Saturn does wobble on a 29.5 year cycle, meaning there are times...
Auroras on Earth are caused by the ionization of atoms high in the atmosphere near the north and south magnetic poles. The solar wind flies toward the Earth and this harmful radiation is blocked and funnelled by our magnetic field, creating harmless, beautiful glows that remind us how close we came to total destruction, but were saved by our planet. Do other planets have auroras? Certainly! Jupiter and Saturn do, and even moons like Ganymede can have auroral activity. It really depends on the magnetic field. So how does a planet like Mars, with no magnetic field, have auroras? This...
Our entire universe, from the tiniest atoms, to the structure of our experiential world, to the most massive galaxy clusters and the cosmic web, is dependent on a set of single properties, where small changes to these fundamental numbers would lead to a state where none of it could exist. Understanding these fundamental numbers is the key to unlocking the deepest secrets of the universe and answering the biggest questions of our existence. One of these numbers is the tiny difference in the masses of the proton and neutron. If it varied even a little bit in either direction, we...
