Happy First Birthday Neptune!

The planet Neptune, as seen by Voyager 2
Neptune, as seen by Voyager 2 (Wikimedia Commons)

Just after midnight on September 23rd, 1846, Johann Gottfried Galle stood at the telescope in the Berlin Observatory, calling out coordinates one by one to his assistant, Heinrich Louis d’Arrest. Despite the lateness of the hour, and the apparent tediousness of the task, there was an uncharacteristic tension in Galle’s voice, a certain expectancy. D’arrest, in the dim candlelight, dutifully checked off each entry on a map of the heavens. “Right ascension: 21 hours, 53 minutes, 16 seconds,” called out Galle. “Declination: negative 13 degrees, 24 minutes, 15 seconds. Magnitude 7.8.” There was a pregnant pause. “Sir,” came the reply, “that star is not on the chart.” The tiny speck of light would turn out to be the last undiscovered planet in the solar system.

Today (July 12, 2011) Neptune will finally celebrate its first anniversary, as it returns to the exact point in its orbit where Galle and D’arrest spotted it all those years ago. Continue reading

Gentle Giant – The Petermann Ice Island

Petermann Ice Island 2010
Calving of the Petermann Ice Island in August 2010. Credit: Jesse Allen and Robert Simmon, NASA Earth Observatory earthobservatory.nasa.gov

Where were you when the Petermann Ice Island calved?

Ok, so maybe the date of August 5, 2010 doesn’t exactly stick in anyone’s memory, but it totally should. That’s the day when an enormous chunk of the Petermann Glacier, on the north-west coast of Greenland, crashed into the sea, creating the biggest piece of floating ice the Arctic had seen in 60 years. Today, the battered remains of this frozen giant are still floating south, and are now within a few hundred kilometres of Newfoundland.

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Boiling Water Trick Explained

A few weeks ago, this video (made by Samantha Stewart of Yellowknife) garnered over a million views on YouTube, and was picked up by both CBC and CNN.  It shows the seemingly magical instant transformation of boiling water into snow, which can only happen at temperatures below -30 C.

Needless to say, I couldn’t wait to try this out for myself.  My opportunity came sooner than I expected; here’s me replicating the experiment from the balcony of my apartment on a typical frigid day in Ottawa.Continue reading

The Tiniest Farmers in the World

Fuligo septica, the “dog vomit” slime mould

Just when you thought slime molds couldn’t get any more bizzare, some researchers at Rice University have caught them farming.

If you are already familiar with slime molds, you can skip over the next couple of paragraphs.  If not, get ready to have your mind blown.

Life, you see, is quite fond of befuddling our attempts to understand it.  While you may have a pretty good idea of what I’m talking about if I say “plant” or “animal” or “fungus” or even “protozoan,” slime molds don’t fit neatly into any of these categories.  In fact, the things commonly lumped together under the title of “slime mould” exhibit a plethora of shapes and behaviours, ranging from things that look more or less like mushrooms (but aren’t) to things that look more or less like dog vomit (see illustration).  Modern DNA analysis shows that different species of slime mould aren’t even that closely related to each other, let alone anything else.Continue reading