After arriving at the mountain after dark, I stayed up as long as I could to get used to a night time observing schedule. I only made it to 1am, which I suppose isn’t that bad given the day of riding I had. As a result, I ended up waking up relatively early the next day and so had some time to look around Kitt Peak. I was particularly interested in Kitt Peak’s outreach and visitor program. There are large number of volunteers that do everything from presentations, tours, observing, and even over night stays with visitors on the mountain.
On Friday the 24th of January 2014, I gave a public talk to the Royal Astronomical Society of Canada, Mississauga Faction. I originally suggested I give a talk on my research, which is focused on black holes, however, the past president Randy Attwood indicated they had already invited my supervisor, Dr. Patrick Hall to talk about that. So I used it as an opportunity to develop a new public talk focussing on planets and dwarf planets, one that I had been wanting to build for a while but hadn’t had the motivation to do so.
I find the topic of ‘dwarf planet’ very interesting, specifically how it surrounds our beloved Pluto. Re-classification is the hallmark of science, as it indicates that people have discovered new things and therefore changed how they view a topic. Re-classifying (note, NOT demoting) Pluto only shows us that astronomers are still putting the puzzle pieces of the solar system together.
The talk I gave was based on a book I read called The Pluto Files: The Rise and Fall of America’s Favorite Planet written by Neil deGrasse Tyson. Dr. Tyson gives a fantastic account of how Pluto was found, and how it was re-classified in the infamous decision of 2006 by the International Astronomical Union (I.A.U.). Definitely check that book out.
Here are the full presentation slides (PDF) that I used for the talk, however, I also employed the help of two friends, Harrison Ruess and Ashley Carr, to video record the talk for me, which I’m currently editing for youtube.
I’ve been working on reducing, plotting, and normalizing Gemini spectra over the last little while. Here’s a final product.
The York University Astronomical Observatory is an undergrad driven research and public outreach machine. Even located under the light-polluted skies of Toronto, it’s still able to do some pretty great imaging. A while back, I tested my hand at astrophotography with some decent results:
While they certainly aren’t Hubble quality, I was pretty happy with what I got. Note isn’t the best the York Observatory can do, the undergrads have some pretty serious talent. Check out the website (linked above) to see some of their great work.
Side story: The objects have the designation M51 and M64 because they are part of the original Messier Catalog created by Charles Messier, a French astronomer who lived from 1730-1817. Messier was a comet hunter. As he toured the night sky looking for comets, he would often run across fuzzy objects (nebulae, clusters, galaxies, etc.) that he didn’t want to mistake for comets in the future. As a result he compiled these objects into the now famous list of ‘Messier objects.’ His original final version of the list was 103 objects long; since then 7 more have been added to make a final total of 110. Nowadays, the Messier Objects are a bunch of fantastic targets for both amateur and professional astronomers alike.
That is a chunk of rock that, until 1947, was in space. It spent the previous 4.568 billion years touring the solar system as one of the many left over pieces of formation (Bouvier & Wadhwa, 2010).
This small piece (owned by the York University Astronomical Observatory) was part of a much bigger object that fell in the Sikhote-Alin mountains of south east Siberia on the 12th of February 1947; as a result it is known as the Sikhote-Alin meteorite.
[Aside: A ‘meteoroid’ is an object much smaller than asteroid (probably part of an asteroid originally) and a ‘meteorite’ is anything that falls to the ground]
The original meteoroid was approximately 90,000 kg – 100,000 kg in mass, and thus far approximately 25 000 kg of that has been recovered. Typical orbital velocities of meteoroids/asteroids in space are tens of km/s. When entering Earth’s atmosphere, the meteoroid will compress the gas in front of it to very high densities. There is a very famous equation that tells us what happens to a gas that has been compressed, called the ideal gas law:
Looking at the equation you can see that if you increase the pressure (P) then the temperature (T) of the gas will also be forced to increase. The other way around, if you decrease the pressure of a gas, its temperature will also decrease. This is something many people may have noticed when using compressed gas in a can, the kind you use to clean computer parts for instance. If you release the gas, the pressure inside the can drops, and the can becomes cold to the touch.
This exact same natural law forces the air in front of a falling meteoroid to very high temperatures. Exposing rock to temperatures of this kind will force it to break up and fall apart. A falling meteoroid may also explode as a result of this sudden increase in pressure on its leading edge, this is known as an air burst.
The Sikhote-Alin fall was probably travelling at about 14 km/s and broke up/exploded at an altitude of approximately 5.6 km (for reference, the Chelyabinsk air burst event air burst at an altitude of 23 km). The fireball and airburst were seen and heard over a geographical area as large as a few hundreds of kilometers.
Many pieces of the Sikhote-Alin meteorite were recovered, allowing researchers to study it in detail. Some highlights: it was mostly made of iron (93%) and nickel (5.9%); this makes it an Iron Meteorite, which are relatively ray (comprising about 6% of all meteorite falls).