Dark matter could be almost anything. With little data other than how much total dark matter mass exists, we can’t decode much about what individual chunks of dark matter might be made of. I’ve talked before about Massive Compact Halo Objects (MACHOs) and Weakly Interacting Massive Particles (WIMPs), but these are just two possibilities. Other theorists have talked about Modified Newtonian Gravity (MNG), where gravity may work differently on the grand scale than it does on our small Earth scales. Or perhaps it’s something I haven’t seen before. Maybe what we call dark matter is just a large population of ancient black holes....
Where do the heavy elements on the periodic table come from? The general answer is from what’s called the r-process of stellar nucleosynthesis. This translates to ‘rapid neutron capture’ being the method by which most of the elements heavier than Iron are formed on the periodic table. This process requires immense energy and was originally thought to only occur within core-collapse supernova explosions. “Understanding how heavy, r-process elements are formed is one of hardest problems in nuclear physics,” said Anna Frebel, assistant professor in the Department of Physics at the Massachusetts Institute of Technology (MIT) and also a member of...
One of the most important questions our species has tackled is the origin of life on Earth. If we can figure out the conditions and catalyst for the beginning of life, we can look elsewhere in the universe for those same conditions, and zero in on the potential for finding extraterrestrial life. We know the universe is old enough for the painstakingly slow evolutionary process, but what started it? In the famous 1952 Miller-Urey experiment, a flask containing the basic natural elements water (H20), methane (CH4), Ammonia (NH4), and Hydrogen (H2), all present on the early Earth, was subjected to...
A pretty cool result came out of Cornell University this week, showing that Mars was struck by a pair of ancient asteroids that caused massive tsunamis. Not only is it the first evidence of a tsunami event on another world, but it proves that Mars once had a large ocean. The study looked at ancient shorelines between the lowlands and highlands of Mars, where the ocean-land boundary would have been. Two massive impacts, a few million years apart, extended the shorelines and caused turmoil with the Martian climate at the time. “About 3.4 billion years ago, a big meteorite impact triggered...
On May 22nd, Mars will be at opposition. It’s the astronomical term for when Mars and the Sun are on opposite sides of the Earth. This makes the face of Mars fully illuminated from Earth, and also brings the Earth to it’s closest approach of Mars, at 75 Million Km. Hubble images the red planet to celebrate the occasion. So get your telescopes out and be ready to take some pictures, because Mars is smiling! Mars will rise in the East at sunset, since they are on opposite sides of the Earth. It will appear bright with a rusty hue, and...
I always get giddy when talking about Europa, as many astronomers do. It’s one of the most fascinating places in our solar system when it comes to the search for life. It has lots of water, likely contained in a subsurface ocean. It’s heated though a gravitational tug of war with Jupiter and the other Galilean moons. And, as of recently, it has a chemical production system that matches Earth’s. I wonder what goes on beneath the thick ice of Europa. Is there an ecosystem filled with alien life down there? Life in Earth’s oceans feels very alien, but creatures from...
Space dust hits the Earth every day in the form of meteorites. As much as 300 tonnes of the stuff falls to the Earth each day. Of course, most of it is dust or small rocks, and goes unnoticed by the majority of people. But every so often, a larger rock plummets to Earth, and if it’s big enough, it will make it’s presence known. One such meteor flew through the atmosphere less than 48 hours ago in the Northeast USA. The bright flashes occur when a space rock, called a meteoroid, hits the atmosphere of the Earth, which rapidly...
This guy is everything you expect in an astronaut. At least that was my first thought when I was looking at his biography. David St. Jacques was one of only two candidates (along with Jeremy Hansen) chosen in the 2008 Canadian Astronaut draft, the third in our nation’s history. He has a degree in Engineering Physics, a Ph.D. in Astrophysics, and is a medical doctor. And that’s just his formal education. He’s an avid mountaineer, cyclist, skier, and sailor. Not to mention his advanced certification as a scuba diver, his commercial pilot’s license, and his ability to converse in Russian, Spanish, and Japanese. And so...
On the heels of my last review, I watched another movie with a space-documentary theme. Though it started out with the human perspective from space, it progressed into so much more. This is the TVO documentary called Planetary. It began with Apollo. Humanity broke the bonds of our world and set foot on another heavenly body. For the first time, we could look back and see the world as it truly is. One of my favourite quotes from the movie came up early, though I’m paraphrasing: We are the Earth, and the Earth is all of us. Seeing the Earth...
Have you seen a gorgeous red sky in the evening, just after sunset? If it’s cloudy, the effect becomes even more spectacular. The Sunlight reflects off the clouds and back down to the ground, creating the calm of twilight. Clouds only go so high, so as the Earth continues to turn and we go deeper into nighttime, the glow disappears. But sometimes it sticks around a bit longer. During a rocket launch at dusk, the exhaust trail from the rocket climbs into the upper atmosphere, far above cloud layers. It can reflect sunlight, with the shape of the particles refracting...
