I was out on a sunny day a few weeks ago waiting for a bus, and as per usual I have my head up in space (I would say up in the clouds but that is too low for me). I noticed the Moon up in the sky, just past first quarter, and I was thinking about the angle of the illuminated side and how it related to some of the positions of the Earth and Sun in space. I wondered what information we could gather from the way it looked. It led me to this ‘illuminating’ post. I realized...
When I do a planetarium show for an audience, and they see the night sky for the first time, I always ask them ‘What do you see?’ The response is the usual stuff – Stars, the Moon, maybe planets, or the Milky Way. But they seem to be missing the most important and largest part of the sky – the Darkness. Space itself. Stars light up the cosmos, but if there were no stars, would we think that the universe was empty? Perhaps, but if you can imagine this scenario, it gives you an important perspective when you want to...
It sounds completely like science fiction, something out of a campy space thriller where the protagonist is a miner taking a daily shuttle to the Moon to mine all the precious metals that the Earth needs to sustain itself. But in real life, for a long time, it was thought that the Moon was a dead rock, completely useless to humanity except as the gravitational force to provide the amazing tides in the bay of Fundy. Today we know so much more about the Moon, and its value has (pun intended) skyrocketed. For one, the low gravity of the Moon...
The Dawn space craft has finally begun its science phase after settling into a 13,500 Km orbit around the dark dwarf planet Ceres. It took some manoeuvring to get it in the right spot, but now it has begun mapping the surface as it slowly orbits once every two weeks. A lovely mosaic image from the space craft is the latest jaw-dropping picture of the former asteroid. Like a great shot of the Lunar terminator, by seeing the shadows created by the light from the Sun, we can get a sense of depth of the heavy craters on the surface....
Our Solar System is so much more than just the eight planets that inhabit it. One of the things I learned a bit later in my career as an astronomer (my teenage years; been doing this for awhile) is how unique and diverse the natural satellites are. Our own moon seems somewhat tame, and it’s easy to think the same of all moons. Many of them are boring quiescent rocks with little more scientific value than asteroids, but the largest hide deep and profound secrets that we are just starting to unlock. Four moons in our solar system are larger...
No, he isn’t a zombie. He’s a long dead scientific pioneer. He discovered Saturn’s moon of Titan and was the first to suggest that Saturn’s odd ‘blob’ shape could be explained by rings around the planet. He was a pioneer of optics and developed a telescope with two lenses, more powerful than Galileos. He also characterized the motion of an ideal mathematical pendulum (with a massless cord and a length longer than its swing), and invented the pendulum clock as a method of keeping time. He had a few other contributions to astronomy, including the observation of individual stars in...
We are fairly confident about the idea that the Moon formed when a Mars sized object hit the young Earth over 4 Billion years ago. The resulting debris cloud condensed to form the Moon, giving the Earth a surprisingly large Moon for its size. Next to Charon and Pluto, the Earth’s Moon is the largest relative to the size of its planet. It’s also the third largest of all moons in the Solar System, next to Ganymede and Titan, #1 and #2 respectively. but there is one problem with this theory of the Moons formation: The Earth and Moon are...
About a year ago I had an idea for a music video. I wanted to take a concept in science and put it to music, making it funny, catchy, memorable, and educational. I wrote out the majority of the lyrics but left it alone for a few months, until I connected with the right friend. My good friend Bob Wegner is a very talented guitarist and audio engineer, and as we spoke about the idea he wanted to be the guy to record it. We spent an afternoon doing the vocals and guitars, and he cleaned it up and made...
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...
When Canadian Astronaut Chris Hadfield was in space, on the International Space Station (ISS), he stayed there for six months, the standard length of stay for an astronaut. On the ISS, three of the six-person crew are replaced every three months. After returning to Earth, Hadfield could barely walk. He had lost bone density and muscle mass, his immune system weakened, cardiovascular functions slowed, and he produced less red blood cells. The lack of gravity is bad for humans, The longest a human being has ever been in space was Russian cosmonaut Valeri Polyakov, who was in space for a staggering...
