As warm as the temperatures have been recently, it may shock you to learn that today marks the Earth’s Aphelion, or its greatest distance from the Sun in its orbit. This may confuse those that think the Earth has seasons due to its proximity to the Sun. The seasons of Earth are actually due to the tilt of the Earth’s axis, and is a result of how much direct sunlight we receive at any given time of year. It’s one of my favourite trivia questions to ask kids in my planetarium shows, and have them guess when the Earth is...
On July 4th, for about an hour and twenty minutes, my heart stopped. This was the amount of time that New Horizons was quiet. No contact, no data, nothing but the lonely black of space. In this time, the craft did what it was programmed to do. It transferred control to its backup computer, which told the main computer to enter safe mode and suspend all non-essential functions. Then the backup computer attempted to re-establish contact with Earth, 5 Billion Kilometres away. Contact has been re-established with the craft and its backup computer has been transmitting telemetry data back to mission...
If you could see through the lens of a very powerful telescope, to an area of sky the size of a grain of sand held at arm’s length, a new universe would be revealed to you. For in that tiny patch of seemingly empty sky, there are thousands of galaxies visible, albeit with many hours of light collection. Observing the most distant of these galaxies, at the edge of the universe, allows us to estimate the number of Galaxies present in the distant past, when the universe was very young. As our observations improve, and our ability to simulate the conditions of the...
When the Rosetta spacecraft entered orbit around comet 67P/Churyumov-Gerasimenko, first images captured deep circular depressions among the other surface features. Now that the orbiter has taken significant observations of the comet’s surface, the science team has concluded that these depressions are actually sinkholes that form by the same processes that form sinkholes 500 Million kilometers away here on Earth. Sinkholes on Earth form when subsurface material is eroded away. Though not initially visible on the surface, the material falls deep underground leaving a circular cavern. Once enough material has eroded away, the top of the cavern collapses, leaving a large...
In the last few days, we have watched the intricate dance of Venus and Jupiter in the Western sky after sunset. They have tangoed and passed by one another and the world has watched as the best conjunction of the year has come and gone. Don’t forget that even though they appear close in the sky, Venus is actually closer to the Earth than it is to Jupiter. Jupiter is hundreds of millions of kilometers further away than Venus. Today’s APOD is a beautiful shot by Letian Wang combining the proximity of the two planets with the (much further East...
As is the case with any final approach to a new object, the early images, with their horrible resolution, pixelated appearance, and possibly false features due to processing, lead to significant speculation on what we will see as the craft approaches. It was the same a few months ago with Ceres. I personally love the blurry images. It’s a mystery waiting to be solved, and we see it unfold as we move ever closer to our destination. It also reminds me of the early days of the internet I grew up with, using a good old 28.8K modem and waiting 2...
For the last few months, Venus and Jupiter have been visible in the night sky. Venus makes it’s usual 584 day cycle, becoming an ‘evening star’ once again, reaching far from the Sun in the West, while still following our central star. Jupiter has slowly worked its way westward over the past few months, due more in part to Earth’s orbit than Jupiter’s. Finally, the long-awaited conjunction of the planets is nigh, and it offers the best views and photographic opportunities of the year for professional and amateur astronomers alike. What is the brightest object in the sky? The Sun...
It’s not fuzzy caterpillars or any small creatures interacting in a Petri dish. The strange growing and twisting creatures are not creatures at all. Today’s NASA APOD shows a time lapse view of a cluster of sunspots as they pass along the surface of the Sun during its rotation. The total time is about 12 hours for the sunspots to cross the solar surface, yet the video is shortened to a quick minute and a half. The amazing thing to notice is the amazing dance of the sunspots as they shift, twist, merge, separate, and interact with the granular convection cells...
I was downtown Toronto this morning, dressed in a suit and holding my umbrella to stay dry and navigate the city streets as they were soaked with rain. I was headed to the CBC building on John street to do an interview about the SpaceX CRS-7 mission that would launch an hour later. This would be a very important mission, the seventh of twelve ISS resupply missions contracted by NASA. It was also the third attempt at a secondary goal – landing the first stage launch vehicle, the Falcon 9 rocket, upright on an ocean platform, a feat that had...
I presume that you know what a leap year is. A year is the amount of time the Earth takes to orbit the Sun, and is measured as 365 days, or 365 rotations of Earth. It is, in reality, a little bit longer. Each orbit of the Sun takes 365.25 days, or 365 days and six hours. So what do we do with that six hours? We ignore it for 3 years. On the fourth year we add up those extra hours and we get 24 hours, an extra day! So we add in February 29th every four years. This...
