The true story of why Pluto isn’t a planet goes back further than you would think. It has a lot to do with our understanding of science at the time, and a lot more to do with surprising luck. I made this video a couple of days ago for the Khan Academy Talent Search. I hope you enjoy it. It will be interesting as we move into better telescope technologies that allow us to see further into the depths of the solar system and the universe. What strange mysteries will we find?
Woman got the worse deal when author John Gray wrote a book titled ‘Men are from Mars, Women are from Venus.’ The point he was clearly making was about the communication issues between the sexes, but men definitely got the better deal in home worlds. For one, Mars is kind of cold, has polar ice caps, is covered in rust and dust, has been pretty dead inside for millions of years, and is bombarded with radiation from the Sun (you can draw your own parallels to men yourself). But Venus, with its 400 degree Celsius temperature, sulphuric acid rain, incredibly...
What is the brightest object in the sky? Why the Sun of course. Second brightest? The Moon. Most people are able to answer this question quite easily, but what is the third brightest? The fourth? Many people will confidently say Sirius, the brightest star in the sky, or Polaris the north star. The answer is that the planet Venus is third and the planet Jupiter is fourth. It shouldn’t be that surprising that planets hold these positions. They are much closer than the distant background of stars, and the human species has been observing them since the dawn of recorded...
I always love to chat about stories by close-to-home scientists. I just talked recently about some University of Waterloo cosmological work, but today I can follow it up with a very close to home scientist that I’ve run into a few times. Something about seeing the achievements of those you know makes you feel pride too – it gives us all a good reason to support friends, colleagues, and even acquaintances, since we can share in their passion. Astronomer Lisa Esteves, a PhD candidate from the University of Toronto, has been watching exoplanets carefully with the Kepler Space Telescope, seeing...
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...
Yesterday I posted some of my own photos of the Moon and Mars in conjunction from the night before. Last night I went out again knowing that there was another planetary conjunction in the works. The Moon was now with Venus. People on the internet and in person were asking me “Mars? I thought the Moon was near Venus,” and “Venus? I thought the Moon was near Mars.” It really speaks to the fact that most people don’t realize how quickly the sky changes from the point of view of an Earthbound observer. So what happened between the Mars-Moon and...
Even though the weather has been insanely cold in Canada the past few weeks, there is an upside for astronomers. Call me a perpetual optimist, but when it’s colder in Canada than it is on Mars, you have to find some kind of silver lining. The upside is that colder weather and clear skies are sometimes synonymous. I’m not a meteorologist so I don’t have any reason to go into detail as to why, but we have had a lot of cold, clear evenings. I’ve had a chance to go outside and test my new DSLR camera, at least for a...
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...
Venus is the most hellish place I know of in the Solar System, and maybe even the broader Universe. Even though Venus looks pretty harmless and is named for the Roman goddess of Love, beneath the soft looking clouds lies sulphuric acid rainfall, 450 degree surface temperatures, and crushing pressure 90 times the atmospheric pressure of Earth at sea level. How do we get the surface picture of Venus above? NASA’s Magellan probe in 1994 finished mapping the surface by looking at Radio wavelengths emitted by the planet and using radar to bounce waves off the surface to measure features....
