Date: July 4th, 2012

Title: Encore: The Moon – Our Sidekick

Podcaster: Rob Berthiaume


This podcast originally aired on April 25, 2010

Description: The moon is really cool to look at, but there’s a deeper connection that astronomers and non-astronomers alike share with our nearest celestial neighbor.

Bio: Robert Berthiaume is a graduate student at York University in Toronto, Canada. When not working in the atomic research lab towards his MSc in Physics, you can probably find him at the university’s observatory, where he is allowed to use a telescope that the bank says he is definitely not allowed to buy.

Today’s Sponsor: “This episode of 365 days of astronomy was sponsored by – Expanding your horizons in astronomy today. The premier on-demand telescope network, at dark sky sites in Spain, New Mexico and Siding Spring, Australia.”

Hi there. I’m Robert Berthiaume , coming to you from the York University Observatory located in Toronto, Canada, where we host public viewing sessions every Wednesday night. Our visitors always bring a slew of questions, most about black holes or killer asteroids. But a few weeks back I got one I’d never heard before.

The Moon had nearly reached its first quarter phase, and as the skies darkened, we moved the telescope towards that bright semi-circle shining in the sky. I enthusiastically explained to the crowd that they’d picked a great week to visit; not only were there clear skies to look at some deep-sky objects, but first, the Moon, a favourite of most astronomers, was in prime viewing position.

The first person took a peek in the eyepiece, and quickly turned to me. “I’m not an astronomy person, so maybe that’s why I don’t get it, but can you explain to me why you’re so excited about the Moon?”

Now I can describe the process of stellar fusion and get fifth graders to understand the radial velocity technique for observing exoplanets. But “Why are you excited to look at the Moon?” had never come up, and I didn’t have an answer ready.

I’ve never had to explain myself. I always thought it was obvious, I mean, look at all those craters and shadows and mountains! Maybe the scope wasn’t focused? Was the tracking off? How was she not excited about the Moon? I soon realized that this person was looking for a deeper answer. Which makes sense I guess: people aren’t excited to see the pyramids because they’re really triangular. There’s more to it, there must be meaning and connection and humanity involved. I got thinking about what it is that peaks people’s interest and excitement when it comes to the Moon.

Well, as an astronomer, a lot of my own excitement comes from actually viewing the Moon. And not just myself, but knowing that the Moon is easy and enjoyable for everyone look at.

One nice thing about the Moon is that it always appears to be changing. For the most part, things in the sky look the same today as they did 3 centuries ago. The Moon, on the other hand, is quite dynamic. From day to day the phases change and at the same time reveal different views of shadows and colours; and even the size changes throughout the year. To see every crater and every mare at every phase would take years of dedicated effort. The Moon, by itself, is like millions of observing opportunities all wrapped up in one.

Views of the Moon are also globally accessible. I’ve seen pictures of the Large Magellenic Cloud but I have yet to make it out of the Northern Hemisphere, and so I’ve never observed these objects myself. I’ll have to take a vacation and spend a bunch of money just to get a glimpse. But no matter where you are I the world, you’ll never be deprived of seeing the Moon.

Furthermore, not only is viewing the Moon independent of position, but time as well. Obviously the best views are at night, but if you have a job or another commitment or a fear of vampires that makes it hard to get out after dark, when it comes to the Moon, you’re in luck. This is of particular help when doing outreach with young children. Most have dinnertimes and bathtimes and bedtimes that often come before it really gets dark outside, but the Moon’s daytime apparitions still allow youngsters to get a glimpse of the heavens.

Now kids often have a harder time seeing things through a telescope. It’s sometimes difficult to explain what patterns and geometries they should be looking for to see the object. I can ask people if they saw Neptune, and it’s no longer surprising if they reply “I don’t know.” When I reveal the Moon to people through a telescope, however, I don’t have any doubt that they can see it.

The Moon is also one of the only things I can let people take home after visiting the observatory. I can show them some star with an exoplanet, but they’ll forget what it’s called and where it is in the sky. But the Moon is something people can look at themselves after they leave, with or without a telescope, which is comforting for me, since it means there’s a chance their visit can be more than a fleeting experience they’ll forget and move on from once they leave.

And the views people have of the Moon are just what they’re expecting. No let downs. The Hubble Space telescope is a hard act to follow. Because our eyes aren’t as sensitive as CCD cameras, we’ll never see spiral arms in galaxies or vividly coloured, high res cloud patterns on Jupiter like we see in magazines or textbooks. But the Moon looks just like the Moon that people expect, and it’s nice to not have to add a disclaimer before letting people look into the scope.

To observe most objects in the sky, it takes about 1 part dark adaption and 99 part imaginations. Looking at the fuzzy blob that is the Andromeda Galaxy is neat, but knowing what it is is much more impressive. It is a collection of one trillion stars located two and a half million light years away. Very impressive, but can anyone tell me how big a light year really is? I’ve never seen one…I don’t know how much a trillion is either. I can’t honestly say I have much of a real-world understanding of what the Andromeda galaxy is. The Moon, on the other hand, is something much more relatable. I can go onto my apartment’s 18th floor balcony, and look out to a road or building 10km away, and have a direct comparison of how big a 10km wide crater on the Moon is. Looking at mountains on the Moon is pretty much like looking at mountains on the Earth. Even the size of the entire Moon is relatable. I’ve driven between a point A and point B that are 3500km apart. That gives me a first-hand feel for the diameter of the Moon, with much less imagination than required to try and size up a nebula that’s a few trillion kilometers wide.

So up to now, the things that excite me about the Moon have everything to do with observing, and the ability to share it with others. But that only concerns astronomers, really. The layperson won’t find many of these things directly appealing. Yet I still see people of all walks of life, their eyes drawn up to the sky to stare at the Moon, as if the two are somehow connected for a few moments.

Maybe we are connected to the Moon. It may be way out in space, but we humans have been there, walking around, sleeping and eating and talking there, the same things we do here in our homes on Earth. Having explored the surface firsthand has given people a new respect for just how fortunate we are to live on our own planet. And the Moon was formed from part of the Earth, some billions of years ago, after a giant impact. So the stuff up there, used to be down here, where we live. And we probably wouldn’t be alive without the Moon. Lunar tides probably played a huge role in the genesis of life here on Earth. And definitely, the stabilizing action of the Moon orbiting around us, like a big gyroscope, has kept Earth’s axial tilt stable throughout the evolution of life, ensuring we don’t seesaw wildly between scorching summers and heatless winters. So there is a much deeper connection than just photons reflected off the surface and entering our pupils.

But most of all, I think astronomers and non-astronomers take some comfort in having the Moon always close to us. And that’s more than just being able to see it day and night, all times of the year, with or without a telescope, from anywhere on the globe. Many are drawn to astronomy because space is a immense, dark, hostile and mysterious place that we want to explore and learn about. But maybe while hearing about lethal black holes and far off quasars and icy comets, people understand, in the back of their minds, that space is immense, dark, hostile, and mysterious place. Its relieving and comforting and nice to know, to me at least, that in a universe full of emptiness and cosmic rays, a universe where light from the nearest galaxy take over two million years to reach us, that we have, and have always had, someone beside us as we journey through the cosmos on this solitary planet of ours. Someone that came from where we come from. Someone that helped us get going. Someone that helps keep us out of trouble. The Moon, our sidekick.

So these are some of the reasons why after years at the eyepiece, I still get excited about the presumably boring old Moon. A lot of these traits may not be unique to the Moon, but it combines all these things and more, including a personal, human connection, which makes it easier to share with people than anything else in the sky.

And I could have fit this somewhere logical in the podcast, but I forgot to mention that if it weren’t for the Moon, we wouldn’t have the eclipses that we do. And eclipses are awesome. So that in itself makes the Moon pretty awesome. With that I’ll wrap up; thanks for listening, until next time, I wish you all clear skies and good times

End of podcast:

365 Days of Astronomy
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